From c70c14bf1b00df7173bb6a3ae2499254ea9d1597 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Fri, 18 Dec 2015 16:16:43 -0500
Subject: [PATCH 001/259] Remove Debug.Trace.

---
 src/Split.hs | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index a39afc2ab..bcfa8f90c 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -18,7 +18,6 @@ import qualified OrderedMap as Map
 import Data.Maybe
 import Data.Monoid
 import qualified Data.Set as Set
-import Debug.Trace
 import Data.List (intersperse)
 
 type ClassName = String
@@ -54,9 +53,6 @@ instance ToMarkup HTML where
   toMarkup (Div className children) = classifyMarkup className . div $ mconcat (toMarkup <$> children)
   toMarkup (Dt key) = dt $ string key
 
-trace' :: Show a => a -> a
-trace' a = traceShow a a
-
 split :: Diff a Info -> String -> String -> IO ByteString
 split diff before after = return . renderHtml
   . docTypeHtml

From eb89e828bba8029d1c821e45b525a1af6e69368c Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Fri, 18 Dec 2015 16:37:16 -0500
Subject: [PATCH 002/259] Add a type parameter to Row.
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Currently it’s a phantom type.
---
 src/Split.hs      | 24 ++++++++++++------------
 test/SplitSpec.hs |  2 +-
 2 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index bcfa8f90c..15a5b73c7 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -74,7 +74,7 @@ split diff before after = return . renderHtml
 
     columnWidth = max (20 + digits maxNumber * 8) 40
 
-    numberRows :: [(Int, Line, Int, Line)] -> Row -> [(Int, Line, Int, Line)]
+    numberRows :: [(Int, Line, Int, Line)] -> Row HTML -> [(Int, Line, Int, Line)]
     numberRows [] (Row EmptyLine EmptyLine) = []
     numberRows [] (Row left@(Line _ _) EmptyLine) = [(1, left, 0, EmptyLine)]
     numberRows [] (Row EmptyLine right@(Line _ _)) = [(0, EmptyLine, 1, right)]
@@ -85,10 +85,10 @@ split diff before after = return . renderHtml
     numberRows rows@((leftCount, _, rightCount, _):_) (Row left right) = (leftCount + 1, left, rightCount + 1, right):rows
 
 
-data Row = Row Line Line
+data Row a = Row Line Line
   deriving Eq
 
-instance Show Row where
+instance Show (Row a) where
   show (Row left right) = "\n" ++ show left ++ " | " ++ show right
 
 instance ToMarkup (Int, Line, Int, Line) where
@@ -136,11 +136,11 @@ instance Monoid Line where
  mappend (Line c xs) EmptyLine = Line c xs
  mappend (Line c1 xs) (Line c2 ys) = Line (c1 || c2) (xs <> ys)
 
-instance Monoid Row where
+instance Monoid (Row a) where
   mempty = Row EmptyLine EmptyLine
   mappend (Row x1 y1) (Row x2 y2) = Row (x1 <> x2) (y1 <> y2)
 
-diffToRows :: Diff a Info -> (Int, Int) -> String -> String -> ([Row], (Range, Range))
+diffToRows :: Diff a Info -> (Int, Int) -> String -> String -> ([Row HTML], (Range, Range))
 diffToRows (Free annotated) _ before after = annotatedToRows annotated before after
 diffToRows (Pure (Insert term)) (previousIndex, _) _ after = (rowWithInsertedLine <$> afterLines, (Range previousIndex previousIndex, range))
   where
@@ -156,7 +156,7 @@ diffToRows (Pure (Replace a b)) _ before after = (replacedRows, (leftRange, righ
   where
     replacedRows = zipWithMaybe rowFromMaybeRows (replace <$> leftElements) (replace <$> rightElements)
     replace = (:[]) . Div (Just "replace") . unLine
-    rowFromMaybeRows :: Maybe [HTML] -> Maybe [HTML] -> Row
+    rowFromMaybeRows :: Maybe [HTML] -> Maybe [HTML] -> Row HTML
     rowFromMaybeRows a b = Row (maybe EmptyLine (Line True) a) (maybe EmptyLine (Line True) b)
     (leftElements, leftRange) = termToLines a before
     (rightElements, rightRange) = termToLines b after
@@ -185,7 +185,7 @@ termToLines (Info range categories :< syntax) source = (rows syntax, range)
     elements = (elementAndBreak $ Span (classify categories)) =<< actualLines (substring range source)
 
 -- | Given an Annotated and before/after strings, returns a list of `Row`s representing the newline-separated diff.
-annotatedToRows :: Annotated a (Info, Info) (Diff a Info) -> String -> String -> ([Row], (Range, Range))
+annotatedToRows :: Annotated a (Info, Info) (Diff a Info) -> String -> String -> ([Row HTML], (Range, Range))
 annotatedToRows (Annotated (Info left leftCategories, Info right rightCategories) syntax) before after = (rows syntax, ranges)
   where
     rows (Leaf _) = zipWithMaybe rowFromMaybeRows leftElements rightElements
@@ -209,7 +209,7 @@ annotatedToRows (Annotated (Info left leftCategories, Info right rightCategories
         allRows = rows ++ separatorRows ++ childRows
         (childRows, childRanges) = diffToRows child previousIndices before after
 
-contextRows :: (Int, Int) -> (Int, Int) -> (String, String) -> [Row]
+contextRows :: (Int, Int) -> (Int, Int) -> (String, String) -> [Row HTML]
 contextRows childIndices previousIndices sources = zipWithMaybe rowFromMaybeRows leftElements rightElements
   where
     leftElements = textElements (Range (fst previousIndices) (fst childIndices)) (fst sources)
@@ -231,13 +231,13 @@ starts (left, right) = (start left, start right)
 ends :: (Range, Range) -> (Int, Int)
 ends (left, right) = (end left, end right)
 
-rowFromMaybeRows :: Maybe HTML -> Maybe HTML -> Row
+rowFromMaybeRows :: Maybe HTML -> Maybe HTML -> (Row HTML)
 rowFromMaybeRows a b = Row (maybe EmptyLine (Line False . (:[])) a) (maybe EmptyLine (Line False . (:[])) b)
 
 maybeLast :: [a] -> Maybe a
 maybeLast list = listToMaybe $ reverse list
 
-adjoin2 :: [Row] -> Row -> [Row]
+adjoin2 :: [Row a] -> Row a -> [Row a]
 adjoin2 [] row = [row]
 
 adjoin2 rows (Row left' right') | Just _ <- openLine $ leftLines rows, Just _ <- openLine $ rightLines rows = zipWith Row lefts rights
@@ -260,12 +260,12 @@ adjoin2 rows (Row left' right') | Just _ <- openLine $ rightLines rows = case le
 
 adjoin2 rows row = row : rows
 
-leftLines :: [Row] -> [Line]
+leftLines :: [Row a] -> [Line]
 leftLines rows = left <$> rows
   where
     left (Row left _) = left
 
-rightLines :: [Row] -> [Line]
+rightLines :: [Row a] -> [Line]
 rightLines rows = right <$> rows
   where
     right (Row _ right) = right
diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index fc71340a5..dc4219869 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -12,7 +12,7 @@ import Control.Monad.Free hiding (unfold)
 import Patch
 import Syntax
 
-instance Arbitrary Row where
+instance Arbitrary (Row a) where
   arbitrary = oneof [
     Row <$> arbitrary <*> arbitrary ]
 

From 7964727da6fbc099ea28a21823636708f535b575 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Fri, 18 Dec 2015 16:41:50 -0500
Subject: [PATCH 003/259] Add a type parameter to Line.

---
 src/Split.hs      | 30 +++++++++++++++---------------
 test/SplitSpec.hs |  2 +-
 2 files changed, 16 insertions(+), 16 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 15a5b73c7..8260cd496 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -74,7 +74,7 @@ split diff before after = return . renderHtml
 
     columnWidth = max (20 + digits maxNumber * 8) 40
 
-    numberRows :: [(Int, Line, Int, Line)] -> Row HTML -> [(Int, Line, Int, Line)]
+    numberRows :: [(Int, Line HTML, Int, Line HTML)] -> Row HTML -> [(Int, Line HTML, Int, Line HTML)]
     numberRows [] (Row EmptyLine EmptyLine) = []
     numberRows [] (Row left@(Line _ _) EmptyLine) = [(1, left, 0, EmptyLine)]
     numberRows [] (Row EmptyLine right@(Line _ _)) = [(0, EmptyLine, 1, right)]
@@ -85,16 +85,16 @@ split diff before after = return . renderHtml
     numberRows rows@((leftCount, _, rightCount, _):_) (Row left right) = (leftCount + 1, left, rightCount + 1, right):rows
 
 
-data Row a = Row Line Line
+data Row a = Row (Line a) (Line a)
   deriving Eq
 
 instance Show (Row a) where
   show (Row left right) = "\n" ++ show left ++ " | " ++ show right
 
-instance ToMarkup (Int, Line, Int, Line) where
+instance ToMarkup (Int, Line a, Int, Line a) where
   toMarkup (m, left, n, right) = tr $ toMarkup (m, left) <> toMarkup (n, right) <> string "\n"
 
-instance ToMarkup (Int, Line) where
+instance ToMarkup (Int, Line a) where
   toMarkup (_, EmptyLine) = numberTd "" <> toMarkup EmptyLine <> string "\n"
   toMarkup (num, line@(Line True _)) = td (string $ show num) ! A.class_ (stringValue "blob-num blob-num-replacement") <> toMarkup line <> string "\n"
   toMarkup (num, line@(Line _ _)) = numberTd (show num) <> toMarkup line <> string "\n"
@@ -108,28 +108,28 @@ codeTd _ Nothing = td mempty ! A.class_ (stringValue "blob-code blob-code-empty
 codeTd True (Just el) = td el ! A.class_ (stringValue "blob-code blob-code-replacement")
 codeTd _ (Just el) = td el ! A.class_ (stringValue "blob-code")
 
-instance ToMarkup Line where
+instance ToMarkup (Line a) where
   toMarkup EmptyLine = codeTd False Nothing
   toMarkup (Line changed html) = codeTd changed . Just . mconcat $ toMarkup <$> html
 
-data Line =
+data Line a =
   Line Bool [HTML]
   | EmptyLine
   deriving Eq
 
-unLine :: Line -> [HTML]
+unLine :: Line a -> [HTML]
 unLine EmptyLine = []
 unLine (Line _ htmls) = htmls
 
-isChanged :: Line -> Bool
+isChanged :: Line a -> Bool
 isChanged EmptyLine = False
 isChanged (Line isChanged _) = isChanged
 
-instance Show Line where
+instance Show (Line a) where
   show (Line change elements) = show change ++ " [" ++ (concat . intersperse ", " $ show <$> elements) ++ "]"
   show EmptyLine = "EmptyLine"
 
-instance Monoid Line where
+instance Monoid (Line a) where
  mempty = EmptyLine
  mappend EmptyLine EmptyLine = EmptyLine
  mappend EmptyLine (Line c ys) = Line c ys
@@ -163,7 +163,7 @@ diffToRows (Pure (Replace a b)) _ before after = (replacedRows, (leftRange, righ
 
 -- | Takes a term and a `source` and returns a list of HTML lines
 -- | and their range within `source`.
-termToLines :: Term a Info -> String -> ([Line], Range)
+termToLines :: Term a Info -> String -> ([Line HTML], Range)
 termToLines (Info range categories :< syntax) source = (rows syntax, range)
   where
     rows (Leaf _) = reverse $ foldl adjoin2Lines [] $ Line True . (:[]) <$> elements
@@ -260,12 +260,12 @@ adjoin2 rows (Row left' right') | Just _ <- openLine $ rightLines rows = case le
 
 adjoin2 rows row = row : rows
 
-leftLines :: [Row a] -> [Line]
+leftLines :: [Row a] -> [Line a]
 leftLines rows = left <$> rows
   where
     left (Row left _) = left
 
-rightLines :: [Row a] -> [Line]
+rightLines :: [Row a] -> [Line a]
 rightLines rows = right <$> rows
   where
     right (Row _ right) = right
@@ -277,12 +277,12 @@ openElement (Dl _ elements) = openElement =<< maybeLast elements
 openElement (Div _ elements) = openElement =<< maybeLast elements
 openElement h = Just h
 
-openLine :: [Line] -> Maybe Line
+openLine :: [Line a] -> Maybe (Line a)
 openLine [] = Nothing
 openLine (EmptyLine : rest) = openLine rest
 openLine (line : _) = const line <$> (openElement =<< (maybeLast $ unLine line))
 
-adjoin2Lines :: [Line] -> Line -> [Line]
+adjoin2Lines :: [Line a] -> Line a -> [Line a]
 adjoin2Lines [] line = [line]
 adjoin2Lines (EmptyLine : xs) line | Just _ <- openLine xs = EmptyLine : adjoin2Lines xs line
 adjoin2Lines (prev:rest) line | Just _ <- openLine [ prev ] = (prev <> line) : rest
diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index dc4219869..a7f29bbfc 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -22,7 +22,7 @@ instance Arbitrary HTML where
     Span <$> arbitrary <*> arbitrary,
     const Break <$> (arbitrary :: Gen ()) ]
 
-instance Arbitrary Line where
+instance Arbitrary (Line a) where
   arbitrary = oneof [
     Line <$> arbitrary <*> arbitrary,
     const EmptyLine <$> (arbitrary :: Gen ()) ]

From 2ede50401ef226f1b142da66bbebcf3d37a1e1ec Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Fri, 18 Dec 2015 16:45:06 -0500
Subject: [PATCH 004/259] Constrain the ToMarkup instances to ToMarkup a.

---
 src/Split.hs | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 8260cd496..3f8f84dea 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -91,11 +91,11 @@ data Row a = Row (Line a) (Line a)
 instance Show (Row a) where
   show (Row left right) = "\n" ++ show left ++ " | " ++ show right
 
-instance ToMarkup (Int, Line a, Int, Line a) where
+instance ToMarkup a => ToMarkup (Int, Line a, Int, Line a) where
   toMarkup (m, left, n, right) = tr $ toMarkup (m, left) <> toMarkup (n, right) <> string "\n"
 
-instance ToMarkup (Int, Line a) where
-  toMarkup (_, EmptyLine) = numberTd "" <> toMarkup EmptyLine <> string "\n"
+instance ToMarkup a => ToMarkup (Int, Line a) where
+  toMarkup (_, line@EmptyLine) = numberTd "" <> toMarkup line <> string "\n"
   toMarkup (num, line@(Line True _)) = td (string $ show num) ! A.class_ (stringValue "blob-num blob-num-replacement") <> toMarkup line <> string "\n"
   toMarkup (num, line@(Line _ _)) = numberTd (show num) <> toMarkup line <> string "\n"
 
@@ -108,7 +108,7 @@ codeTd _ Nothing = td mempty ! A.class_ (stringValue "blob-code blob-code-empty
 codeTd True (Just el) = td el ! A.class_ (stringValue "blob-code blob-code-replacement")
 codeTd _ (Just el) = td el ! A.class_ (stringValue "blob-code")
 
-instance ToMarkup (Line a) where
+instance ToMarkup a => ToMarkup (Line a) where
   toMarkup EmptyLine = codeTd False Nothing
   toMarkup (Line changed html) = codeTd changed . Just . mconcat $ toMarkup <$> html
 

From 9ec602ee821d1476bb249557e9c5a505972a6372 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Fri, 18 Dec 2015 17:33:45 -0500
Subject: [PATCH 005/259] The Show instances are constrained to `Show a`.

---
 src/Split.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 3f8f84dea..43bd4bd6e 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -88,7 +88,7 @@ split diff before after = return . renderHtml
 data Row a = Row (Line a) (Line a)
   deriving Eq
 
-instance Show (Row a) where
+instance Show a => Show (Row a) where
   show (Row left right) = "\n" ++ show left ++ " | " ++ show right
 
 instance ToMarkup a => ToMarkup (Int, Line a, Int, Line a) where
@@ -125,7 +125,7 @@ isChanged :: Line a -> Bool
 isChanged EmptyLine = False
 isChanged (Line isChanged _) = isChanged
 
-instance Show (Line a) where
+instance Show a => Show (Line a) where
   show (Line change elements) = show change ++ " [" ++ (concat . intersperse ", " $ show <$> elements) ++ "]"
   show EmptyLine = "EmptyLine"
 

From 5089c1d2ed1ece77d7ea8540af2995613b3f0bbf Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Fri, 18 Dec 2015 17:34:08 -0500
Subject: [PATCH 006/259] Rename the unLine parameter.

---
 src/Split.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index 43bd4bd6e..004376a72 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -119,7 +119,7 @@ data Line a =
 
 unLine :: Line a -> [HTML]
 unLine EmptyLine = []
-unLine (Line _ htmls) = htmls
+unLine (Line _ elements) = elements
 
 isChanged :: Line a -> Bool
 isChanged EmptyLine = False

From 3ec55a34a4e0f300ba2b3ce33859714e0128a45c Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 09:52:27 -0500
Subject: [PATCH 007/259] Add a generalization of openLine, parameterized by
 the selection of an open element.

---
 src/Split.hs | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/Split.hs b/src/Split.hs
index 004376a72..f25f35c57 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -282,6 +282,11 @@ openLine [] = Nothing
 openLine (EmptyLine : rest) = openLine rest
 openLine (line : _) = const line <$> (openElement =<< (maybeLast $ unLine line))
 
+openLineBy :: (a -> Maybe a) -> [Line a] -> Maybe (Line a)
+openLineBy _ [] = Nothing
+openLineBy f (EmptyLine : rest) = openLineBy f rest
+openLineBy f (line : _) = const line <$> (f =<< (maybeLast $ unLine line))
+
 adjoin2Lines :: [Line a] -> Line a -> [Line a]
 adjoin2Lines [] line = [line]
 adjoin2Lines (EmptyLine : xs) line | Just _ <- openLine xs = EmptyLine : adjoin2Lines xs line

From afafed623c6da4fd914b00cb7617541bed2a2f4f Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 09:52:41 -0500
Subject: [PATCH 008/259] Define openLine in terms of openLineBy.

---
 src/Split.hs | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index f25f35c57..ca7a09694 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -277,10 +277,8 @@ openElement (Dl _ elements) = openElement =<< maybeLast elements
 openElement (Div _ elements) = openElement =<< maybeLast elements
 openElement h = Just h
 
-openLine :: [Line a] -> Maybe (Line a)
-openLine [] = Nothing
-openLine (EmptyLine : rest) = openLine rest
-openLine (line : _) = const line <$> (openElement =<< (maybeLast $ unLine line))
+openLine :: [Line HTML] -> Maybe (Line HTML)
+openLine lines = openLineBy openElement lines
 
 openLineBy :: (a -> Maybe a) -> [Line a] -> Maybe (Line a)
 openLineBy _ [] = Nothing

From 05785a0b0673c871a2aafc445445aed007822c79 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 09:52:57 -0500
Subject: [PATCH 009/259] Add a generalization of adjoin2Lines, parameterized
 by the selection of an open element.

---
 src/Split.hs | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/Split.hs b/src/Split.hs
index ca7a09694..91f574182 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -291,6 +291,12 @@ adjoin2Lines (EmptyLine : xs) line | Just _ <- openLine xs = EmptyLine : adjoin2
 adjoin2Lines (prev:rest) line | Just _ <- openLine [ prev ] = (prev <> line) : rest
 adjoin2Lines lines line = line : lines
 
+adjoin2LinesBy :: (a -> Maybe a) -> [Line a] -> Line a -> [Line a]
+adjoin2LinesBy _ [] line = [line]
+adjoin2LinesBy f (EmptyLine : xs) line | Just _ <- openLineBy f xs = EmptyLine : adjoin2LinesBy f xs line
+adjoin2LinesBy f (prev:rest) line | Just _ <- openLineBy f [ prev ] = (prev <> line) : rest
+adjoin2LinesBy _ lines line = line : lines
+
 zipWithMaybe :: (Maybe a -> Maybe b -> c) -> [a] -> [b] -> [c]
 zipWithMaybe f la lb = take len $ zipWith f la' lb'
   where

From 4c0b6e963634d23021632b14ba6fde7567ebe9f4 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 09:53:37 -0500
Subject: [PATCH 010/259] Define adjoin2Lines in terms of adjoin2LinesBy.

---
 src/Split.hs | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 91f574182..b88bbc4a9 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -285,11 +285,8 @@ openLineBy _ [] = Nothing
 openLineBy f (EmptyLine : rest) = openLineBy f rest
 openLineBy f (line : _) = const line <$> (f =<< (maybeLast $ unLine line))
 
-adjoin2Lines :: [Line a] -> Line a -> [Line a]
-adjoin2Lines [] line = [line]
-adjoin2Lines (EmptyLine : xs) line | Just _ <- openLine xs = EmptyLine : adjoin2Lines xs line
-adjoin2Lines (prev:rest) line | Just _ <- openLine [ prev ] = (prev <> line) : rest
-adjoin2Lines lines line = line : lines
+adjoin2Lines :: [Line HTML] -> Line HTML -> [Line HTML]
+adjoin2Lines = adjoin2LinesBy openElement
 
 adjoin2LinesBy :: (a -> Maybe a) -> [Line a] -> Line a -> [Line a]
 adjoin2LinesBy _ [] line = [line]

From b8e843a50548406878b8eda81b06267da5761482 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 09:53:49 -0500
Subject: [PATCH 011/259] Spacing.

---
 src/Split.hs | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index b88bbc4a9..f475933d2 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -5,7 +5,6 @@ import Diff
 import Patch
 import Term
 import Syntax
-
 import Control.Comonad.Cofree
 import Range
 import Control.Monad.Free

From a9c744a54c5eb14fc4765081345279e1258a9b7b Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 09:54:03 -0500
Subject: [PATCH 012/259] Eta-reduce the openLine definition.

---
 src/Split.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index f475933d2..c6f059d88 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -277,7 +277,7 @@ openElement (Div _ elements) = openElement =<< maybeLast elements
 openElement h = Just h
 
 openLine :: [Line HTML] -> Maybe (Line HTML)
-openLine lines = openLineBy openElement lines
+openLine = openLineBy openElement
 
 openLineBy :: (a -> Maybe a) -> [Line a] -> Maybe (Line a)
 openLineBy _ [] = Nothing

From f714e83b62805184b294139be74f01f35db307b7 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 09:56:33 -0500
Subject: [PATCH 013/259] Define adjoin2 in terms of its generalization over
 the selection of an open element.

---
 src/Split.hs | 23 +++++++++++++----------
 1 file changed, 13 insertions(+), 10 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index c6f059d88..9bbf408a9 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -236,28 +236,31 @@ rowFromMaybeRows a b = Row (maybe EmptyLine (Line False . (:[])) a) (maybe Empty
 maybeLast :: [a] -> Maybe a
 maybeLast list = listToMaybe $ reverse list
 
-adjoin2 :: [Row a] -> Row a -> [Row a]
-adjoin2 [] row = [row]
+adjoin2 :: [Row HTML] -> Row HTML -> [Row HTML]
+adjoin2 = adjoin2By openElement
 
-adjoin2 rows (Row left' right') | Just _ <- openLine $ leftLines rows, Just _ <- openLine $ rightLines rows = zipWith Row lefts rights
-  where lefts = adjoin2Lines (leftLines rows) left'
-        rights = adjoin2Lines (rightLines rows) right'
+adjoin2By :: (a -> Maybe a) -> [Row a] -> Row a -> [Row a]
+adjoin2By _ [] row = [row]
 
-adjoin2 rows (Row left' right') | Just _ <- openLine $ leftLines rows = case right' of
+adjoin2By f rows (Row left' right') | Just _ <- openLineBy f $ leftLines rows, Just _ <- openLineBy f $ rightLines rows = zipWith Row lefts rights
+  where lefts = adjoin2LinesBy f (leftLines rows) left'
+        rights = adjoin2LinesBy f (rightLines rows) right'
+
+adjoin2By f rows (Row left' right') | Just _ <- openLineBy f $ leftLines rows = case right' of
   EmptyLine -> rest
   _ -> Row EmptyLine right' : rest
   where rest = zipWith Row lefts rights
-        lefts = adjoin2Lines (leftLines rows) left'
+        lefts = adjoin2LinesBy f (leftLines rows) left'
         rights = rightLines rows
 
-adjoin2 rows (Row left' right') | Just _ <- openLine $ rightLines rows = case left' of
+adjoin2By f rows (Row left' right') | Just _ <- openLineBy f $ rightLines rows = case left' of
   EmptyLine -> rest
   _ -> Row left' EmptyLine : rest
   where rest = zipWith Row lefts rights
         lefts = leftLines rows
-        rights = adjoin2Lines (rightLines rows) right'
+        rights = adjoin2LinesBy f (rightLines rows) right'
 
-adjoin2 rows row = row : rows
+adjoin2By _ rows row = row : rows
 
 leftLines :: [Row a] -> [Line a]
 leftLines rows = left <$> rows

From 3424df075acb7f44fe9828b3f92a56f90d3bea99 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 09:58:02 -0500
Subject: [PATCH 014/259] Generalize Line and unLine over a.

---
 src/Split.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 9bbf408a9..861dbbafe 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -112,11 +112,11 @@ instance ToMarkup a => ToMarkup (Line a) where
   toMarkup (Line changed html) = codeTd changed . Just . mconcat $ toMarkup <$> html
 
 data Line a =
-  Line Bool [HTML]
+  Line Bool [a]
   | EmptyLine
   deriving Eq
 
-unLine :: Line a -> [HTML]
+unLine :: Line a -> [a]
 unLine EmptyLine = []
 unLine (Line _ elements) = elements
 

From c9f13f2f413c3741599e99c6770535c91823f16c Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 09:58:20 -0500
Subject: [PATCH 015/259] Define the arbitrary instances for Row and Line in
 terms of an Arbitrary type a.

---
 test/SplitSpec.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index a7f29bbfc..f5c5810c3 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -12,7 +12,7 @@ import Control.Monad.Free hiding (unfold)
 import Patch
 import Syntax
 
-instance Arbitrary (Row a) where
+instance Arbitrary a => Arbitrary (Row a) where
   arbitrary = oneof [
     Row <$> arbitrary <*> arbitrary ]
 
@@ -22,7 +22,7 @@ instance Arbitrary HTML where
     Span <$> arbitrary <*> arbitrary,
     const Break <$> (arbitrary :: Gen ()) ]
 
-instance Arbitrary (Line a) where
+instance Arbitrary a => Arbitrary (Line a) where
   arbitrary = oneof [
     Line <$> arbitrary <*> arbitrary,
     const EmptyLine <$> (arbitrary :: Gen ()) ]

From 9404ee75c3537d65d0eef504c3319ec26f7c9870 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 10:01:00 -0500
Subject: [PATCH 016/259] Test openLineBy, not openLine.

---
 test/SplitSpec.hs | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index f5c5810c3..4d698da23 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -142,16 +142,16 @@ spec = do
         Line True [ span "*/" ]
       ], Range 0 5)
 
-  describe "openLine" $ do
+  describe "openLineBy" $ do
     it "should produce the earliest non-empty line in a list, if open" $
-      openLine [
+      openLineBy openElement [
         Line True [ Div (Just "delete") [ span "*/" ] ],
         Line True [ Div (Just "delete") [ span " * Debugging", Break ] ],
         Line True [ Div (Just "delete") [ span "/*", Break ] ]
       ] `shouldBe` (Just $ Line True [ Div (Just "delete") [ span "*/" ] ])
 
     it "should return Nothing if the earliest non-empty line is closed" $
-      openLine [
+      openLineBy openElement [
         Line True [ Div (Just "delete") [ span " * Debugging", Break ] ]
       ] `shouldBe` Nothing
 
@@ -167,6 +167,6 @@ spec = do
       offsetInfo by (Info (Range start end) categories) = Info (Range (start + by) (end + by)) categories
       offsetAnnotated by1 by2 (Annotated (left, right) syntax) = Annotated (offsetInfo by1 left, offsetInfo by2 right) syntax
       span = Span (Just "category-leaf")
-      isOpen (Row a b) = (maybe False (const True) $ openLine [ a ]) && (maybe False (const True) $ openLine [ b ])
-      isClosed (Row a@(Line _ _) b@(Line _ _)) = (maybe True (const False) $ openLine [ a ]) && (maybe True (const False) $ openLine [ b ])
+      isOpen (Row a b) = (maybe False (const True) $ openLineBy openElement [ a ]) && (maybe False (const True) $ openLineBy openElement [ b ])
+      isClosed (Row a@(Line _ _) b@(Line _ _)) = (maybe True (const False) $ openLineBy openElement [ a ]) && (maybe True (const False) $ openLineBy openElement [ b ])
       isClosed (Row _ _) = False

From e92d4037fd9685b4755769bbc40acfa4168a907e Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 10:01:03 -0500
Subject: [PATCH 017/259] Remove openLine.

---
 src/Split.hs | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 861dbbafe..7aa38982b 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -279,9 +279,6 @@ openElement (Dl _ elements) = openElement =<< maybeLast elements
 openElement (Div _ elements) = openElement =<< maybeLast elements
 openElement h = Just h
 
-openLine :: [Line HTML] -> Maybe (Line HTML)
-openLine = openLineBy openElement
-
 openLineBy :: (a -> Maybe a) -> [Line a] -> Maybe (Line a)
 openLineBy _ [] = Nothing
 openLineBy f (EmptyLine : rest) = openLineBy f rest

From 422dad44a910899c0ad4b2b1ae3c274d98308500 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 10:03:03 -0500
Subject: [PATCH 018/259] Define termToLines in terms of adjoin2LinesBy.

---
 src/Split.hs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 7aa38982b..55f2fdf39 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -165,7 +165,7 @@ diffToRows (Pure (Replace a b)) _ before after = (replacedRows, (leftRange, righ
 termToLines :: Term a Info -> String -> ([Line HTML], Range)
 termToLines (Info range categories :< syntax) source = (rows syntax, range)
   where
-    rows (Leaf _) = reverse $ foldl adjoin2Lines [] $ Line True . (:[]) <$> elements
+    rows (Leaf _) = reverse $ foldl (adjoin2LinesBy openElement) [] $ Line True . (:[]) <$> elements
     rows (Indexed i) = rewrapLineContentsIn Ul <$> childLines i
     rows (Fixed f) = rewrapLineContentsIn Ul <$> childLines f
     rows (Keyed k) = rewrapLineContentsIn Dl <$> childLines k
@@ -174,12 +174,12 @@ termToLines (Info range categories :< syntax) source = (rows syntax, range)
     rewrapLineContentsIn _ EmptyLine = EmptyLine
     lineElements r s = Line True . (:[]) <$> textElements r s
     childLines i = appendRemainder $ foldl sumLines ([], start range) i
-    appendRemainder (lines, previous) = reverse . foldl adjoin2Lines [] $ lines ++ lineElements (Range previous (end range)) source
+    appendRemainder (lines, previous) = reverse . foldl (adjoin2LinesBy openElement) [] $ lines ++ lineElements (Range previous (end range)) source
     sumLines (lines, previous) child = (allLines, end childRange)
       where
         separatorLines = lineElements (Range previous $ start childRange) source
         unadjoinedLines = lines ++ separatorLines ++ childLines
-        allLines = reverse $ foldl adjoin2Lines [] unadjoinedLines
+        allLines = reverse $ foldl (adjoin2LinesBy openElement) [] unadjoinedLines
         (childLines, childRange) = termToLines child source
     elements = (elementAndBreak $ Span (classify categories)) =<< actualLines (substring range source)
 

From c19dbc27b0935ce1ceec19398a5df8af933ac50c Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 10:03:08 -0500
Subject: [PATCH 019/259] Remove adjoin2Lines.

---
 src/Split.hs | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 55f2fdf39..17a43ddaf 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -284,9 +284,6 @@ openLineBy _ [] = Nothing
 openLineBy f (EmptyLine : rest) = openLineBy f rest
 openLineBy f (line : _) = const line <$> (f =<< (maybeLast $ unLine line))
 
-adjoin2Lines :: [Line HTML] -> Line HTML -> [Line HTML]
-adjoin2Lines = adjoin2LinesBy openElement
-
 adjoin2LinesBy :: (a -> Maybe a) -> [Line a] -> Line a -> [Line a]
 adjoin2LinesBy _ [] line = [line]
 adjoin2LinesBy f (EmptyLine : xs) line | Just _ <- openLineBy f xs = EmptyLine : adjoin2LinesBy f xs line

From 9ef0242ac824a1d3bfa9f6654f627061f4749775 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 10:04:02 -0500
Subject: [PATCH 020/259] Define annotatedToRows in terms of adjoin2By.

---
 src/Split.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index 17a43ddaf..0ecfe564e 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -201,7 +201,7 @@ annotatedToRows (Annotated (Info left leftCategories, Info right rightCategories
     ranges = (left, right)
     sources = (before, after)
     childRows = appendRemainder . foldl sumRows ([], starts ranges)
-    appendRemainder (rows, previousIndices) = reverse . foldl adjoin2 [] $ rows ++ (contextRows (ends ranges) previousIndices sources)
+    appendRemainder (rows, previousIndices) = reverse . foldl (adjoin2By openElement) [] $ rows ++ (contextRows (ends ranges) previousIndices sources)
     sumRows (rows, previousIndices) child = (allRows, ends childRanges)
       where
         separatorRows = contextRows (starts childRanges) previousIndices sources

From 446383565c99c9d759b56f8159ee6785ab1116ad Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 10:04:47 -0500
Subject: [PATCH 021/259] Test adjoin2By.

---
 test/SplitSpec.hs | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 4d698da23..898849971 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -112,26 +112,26 @@ spec = do
             ([ Row (Line False [ span "t\776" ]) (Line False [ span "\7831"]) ], (Range 0 2, Range 0 1))
 
 
-  describe "adjoin2" $ do
+  describe "adjoin2By" $ do
     prop "is identity on top of no rows" $
-      \ a -> adjoin2 [] a == [ a ]
+      \ a -> adjoin2By openElement [] a == [ a ]
 
     prop "appends onto open rows" $
       forAll ((arbitrary `suchThat` isOpen) >>= \ a -> ((,) a) <$> (arbitrary `suchThat` isOpen)) $
         \ (a@(Row (Line ac1 as1) (Line bc1 bs1)), b@(Row (Line ac2 as2) (Line bc2 bs2))) ->
-          adjoin2 [ a ] b `shouldBe` [ Row (Line (ac1 || ac2) $ as1 ++ as2) (Line (bc1 || bc2) $ bs1 ++ bs2) ]
+          adjoin2By openElement [ a ] b `shouldBe` [ Row (Line (ac1 || ac2) $ as1 ++ as2) (Line (bc1 || bc2) $ bs1 ++ bs2) ]
 
     prop "does not append onto closed rows" $
       forAll ((arbitrary `suchThat` isClosed) >>= \ a -> ((,) a) <$> (arbitrary `suchThat` isClosed)) $
-        \ (a, b) -> adjoin2 [ a ] b `shouldBe` [ b, a ]
+        \ (a, b) -> adjoin2By openElement [ a ] b `shouldBe` [ b, a ]
 
     prop "does not promote elements through empty lines onto closed lines" $
       forAll ((arbitrary `suchThat` isClosed) >>= \ a -> ((,) a) <$> (arbitrary `suchThat` isClosed)) $
-        \ (a, b) -> adjoin2 [ Row EmptyLine EmptyLine, a ] b `shouldBe` [ b, Row EmptyLine EmptyLine, a ]
+        \ (a, b) -> adjoin2By openElement [ Row EmptyLine EmptyLine, a ] b `shouldBe` [ b, Row EmptyLine EmptyLine, a ]
 
     prop "promotes elements through empty lines onto open lines" $
       forAll ((arbitrary `suchThat` isOpen) >>= \ a -> ((,) a) <$> (arbitrary `suchThat` isOpen)) $
-        \ (a, b) -> adjoin2 [ Row EmptyLine EmptyLine, a ] b `shouldBe` Row EmptyLine EmptyLine : adjoin2 [ a ] b
+        \ (a, b) -> adjoin2By openElement [ Row EmptyLine EmptyLine, a ] b `shouldBe` Row EmptyLine EmptyLine : adjoin2By openElement [ a ] b
 
   describe "termToLines" $ do
     it "splits multi-line terms into multiple lines" $

From 4b487669a968784d7de737f9fd0e0246a90bec0a Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 10:04:51 -0500
Subject: [PATCH 022/259] Remove adjoin2.

---
 src/Split.hs | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 0ecfe564e..26a023348 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -236,9 +236,6 @@ rowFromMaybeRows a b = Row (maybe EmptyLine (Line False . (:[])) a) (maybe Empty
 maybeLast :: [a] -> Maybe a
 maybeLast list = listToMaybe $ reverse list
 
-adjoin2 :: [Row HTML] -> Row HTML -> [Row HTML]
-adjoin2 = adjoin2By openElement
-
 adjoin2By :: (a -> Maybe a) -> [Row a] -> Row a -> [Row a]
 adjoin2By _ [] row = [row]
 

From 09fb6238c4b73731e4eb76d19600159a63a5f9aa Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 10:05:49 -0500
Subject: [PATCH 023/259] Remove isChanged.

---
 src/Split.hs | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 26a023348..2127d2758 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -120,10 +120,6 @@ unLine :: Line a -> [a]
 unLine EmptyLine = []
 unLine (Line _ elements) = elements
 
-isChanged :: Line a -> Bool
-isChanged EmptyLine = False
-isChanged (Line isChanged _) = isChanged
-
 instance Show a => Show (Line a) where
   show (Line change elements) = show change ++ " [" ++ (concat . intersperse ", " $ show <$> elements) ++ "]"
   show EmptyLine = "EmptyLine"

From 3d17c9a8f0e3f3a86a2a1c37dc5778e7d215c425 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 10:12:14 -0500
Subject: [PATCH 024/259] Use an operator section to avoid some awkwardness.

---
 src/Split.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index 2127d2758..adb16a4d8 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -58,7 +58,7 @@ split diff before after = return . renderHtml
     . ((head $ link ! A.rel (stringValue "stylesheet") ! A.href (stringValue "style.css")) <>)
     . body
       . (table ! A.class_ (stringValue "diff")) $
-        ((<>) (colgroup $ (col ! A.width (stringValue . show $ columnWidth)) <> col <> (col ! A.width (stringValue . show $ columnWidth)) <> col))
+        ((colgroup $ (col ! A.width (stringValue . show $ columnWidth)) <> col <> (col ! A.width (stringValue . show $ columnWidth)) <> col) <>)
         . mconcat $ toMarkup <$> reverse numbered
   where
     rows = fst $ diffToRows diff (0, 0) before after

From 058d8d89f966528338b78bf4af77c296d1facb01 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 10:14:12 -0500
Subject: [PATCH 025/259] Use logBase.

---
 src/Split.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index adb16a4d8..6d6844f9a 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -69,7 +69,7 @@ split diff before after = return . renderHtml
 
     digits :: Int -> Int
     digits n = let base = 10 :: Int in
-      ceiling (log(fromIntegral n) / log(fromIntegral base) :: Double)
+      ceiling (logBase (fromIntegral base) (fromIntegral n) :: Double)
 
     columnWidth = max (20 + digits maxNumber * 8) 40
 

From 5f01b38d53da48ecc0877cfb44f0138515e876f3 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 10:15:26 -0500
Subject: [PATCH 026/259] Intercalate!

---
 src/Split.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 6d6844f9a..c03def46e 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -17,7 +17,7 @@ import qualified OrderedMap as Map
 import Data.Maybe
 import Data.Monoid
 import qualified Data.Set as Set
-import Data.List (intersperse)
+import Data.List (intercalate)
 
 type ClassName = String
 
@@ -121,7 +121,7 @@ unLine EmptyLine = []
 unLine (Line _ elements) = elements
 
 instance Show a => Show (Line a) where
-  show (Line change elements) = show change ++ " [" ++ (concat . intersperse ", " $ show <$> elements) ++ "]"
+  show (Line change elements) = show change ++ " [" ++ (intercalate ", " $ show <$> elements) ++ "]"
   show EmptyLine = "EmptyLine"
 
 instance Monoid (Line a) where

From b8c21e96af28a836a3f53ee9d1e36594f699cdee Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 10:16:42 -0500
Subject: [PATCH 027/259] Apply all the linter feedback.

---
 src/Split.hs | 26 +++++++++++++-------------
 1 file changed, 13 insertions(+), 13 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index c03def46e..77b6a4233 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -121,7 +121,7 @@ unLine EmptyLine = []
 unLine (Line _ elements) = elements
 
 instance Show a => Show (Line a) where
-  show (Line change elements) = show change ++ " [" ++ (intercalate ", " $ show <$> elements) ++ "]"
+  show (Line change elements) = show change ++ " [" ++ intercalate ", " (show <$> elements) ++ "]"
   show EmptyLine = "EmptyLine"
 
 instance Monoid (Line a) where
@@ -177,7 +177,7 @@ termToLines (Info range categories :< syntax) source = (rows syntax, range)
         unadjoinedLines = lines ++ separatorLines ++ childLines
         allLines = reverse $ foldl (adjoin2LinesBy openElement) [] unadjoinedLines
         (childLines, childRange) = termToLines child source
-    elements = (elementAndBreak $ Span (classify categories)) =<< actualLines (substring range source)
+    elements = elementAndBreak (Span $ classify categories) =<< actualLines (substring range source)
 
 -- | Given an Annotated and before/after strings, returns a list of `Row`s representing the newline-separated diff.
 annotatedToRows :: Annotated a (Info, Info) (Diff a Info) -> String -> String -> ([Row HTML], (Range, Range))
@@ -188,8 +188,8 @@ annotatedToRows (Annotated (Info left leftCategories, Info right rightCategories
     rows (Fixed f) = rewrapRowContentsIn Ul <$> childRows f
     rows (Keyed k) = rewrapRowContentsIn Dl <$> childRows (snd <$> Map.toList k)
 
-    leftElements = (elementAndBreak $ Span (classify leftCategories)) =<< actualLines (substring left before)
-    rightElements = (elementAndBreak $ Span (classify rightCategories)) =<< actualLines (substring right after)
+    leftElements = elementAndBreak (Span $ classify leftCategories) =<< actualLines (substring left before)
+    rightElements = elementAndBreak (Span $ classify rightCategories) =<< actualLines (substring right after)
 
     wrap _ EmptyLine = EmptyLine
     wrap f (Line c elements) = Line c [ f elements ]
@@ -197,7 +197,7 @@ annotatedToRows (Annotated (Info left leftCategories, Info right rightCategories
     ranges = (left, right)
     sources = (before, after)
     childRows = appendRemainder . foldl sumRows ([], starts ranges)
-    appendRemainder (rows, previousIndices) = reverse . foldl (adjoin2By openElement) [] $ rows ++ (contextRows (ends ranges) previousIndices sources)
+    appendRemainder (rows, previousIndices) = reverse . foldl (adjoin2By openElement) [] $ rows ++ contextRows (ends ranges) previousIndices sources
     sumRows (rows, previousIndices) child = (allRows, ends childRanges)
       where
         separatorRows = contextRows (starts childRanges) previousIndices sources
@@ -217,7 +217,7 @@ elementAndBreak constructor x | '\n' <- last x = [ constructor $ init x, Break ]
 elementAndBreak constructor x = [ constructor x ]
 
 textElements :: Range -> String -> [HTML]
-textElements range source = (elementAndBreak Text) =<< actualLines s
+textElements range source = elementAndBreak Text =<< actualLines s
   where s = substring range source
 
 starts :: (Range , Range) -> (Int, Int)
@@ -226,7 +226,7 @@ starts (left, right) = (start left, start right)
 ends :: (Range, Range) -> (Int, Int)
 ends (left, right) = (end left, end right)
 
-rowFromMaybeRows :: Maybe HTML -> Maybe HTML -> (Row HTML)
+rowFromMaybeRows :: Maybe HTML -> Maybe HTML -> Row HTML
 rowFromMaybeRows a b = Row (maybe EmptyLine (Line False . (:[])) a) (maybe EmptyLine (Line False . (:[])) b)
 
 maybeLast :: [a] -> Maybe a
@@ -275,7 +275,7 @@ openElement h = Just h
 openLineBy :: (a -> Maybe a) -> [Line a] -> Maybe (Line a)
 openLineBy _ [] = Nothing
 openLineBy f (EmptyLine : rest) = openLineBy f rest
-openLineBy f (line : _) = const line <$> (f =<< (maybeLast $ unLine line))
+openLineBy f (line : _) = const line <$> (f =<< maybeLast (unLine line))
 
 adjoin2LinesBy :: (a -> Maybe a) -> [Line a] -> Line a -> [Line a]
 adjoin2LinesBy _ [] line = [line]
@@ -287,8 +287,8 @@ zipWithMaybe :: (Maybe a -> Maybe b -> c) -> [a] -> [b] -> [c]
 zipWithMaybe f la lb = take len $ zipWith f la' lb'
   where
     len = max (length la) (length lb)
-    la' = (Just <$> la) ++ (repeat Nothing)
-    lb' = (Just <$> lb) ++ (repeat Nothing)
+    la' = (Just <$> la) ++ repeat Nothing
+    lb' = (Just <$> lb) ++ repeat Nothing
 
 classify :: Set.Set Category -> Maybe ClassName
 classify = foldr (const . Just . ("category-" ++)) Nothing
@@ -296,6 +296,6 @@ classify = foldr (const . Just . ("category-" ++)) Nothing
 actualLines :: String -> [String]
 actualLines "" = [""]
 actualLines lines = case break (== '\n') lines of
-  (l, lines') -> (case lines' of
-                       [] -> [ l ]
-                       _:lines' -> (l ++ "\n") : actualLines lines')
+  (l, lines') -> case lines' of
+                      [] -> [ l ]
+                      _:lines' -> (l ++ "\n") : actualLines lines'

From 0823ca7f698bdb426e87f782c68e6bb5a0506b30 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 11:01:44 -0500
Subject: [PATCH 028/259] Move starts/ends into the where clause.

---
 src/Split.hs | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 77b6a4233..a8e5efb6d 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -198,6 +198,8 @@ annotatedToRows (Annotated (Info left leftCategories, Info right rightCategories
     sources = (before, after)
     childRows = appendRemainder . foldl sumRows ([], starts ranges)
     appendRemainder (rows, previousIndices) = reverse . foldl (adjoin2By openElement) [] $ rows ++ contextRows (ends ranges) previousIndices sources
+    starts (left, right) = (start left, start right)
+    ends (left, right) = (end left, end right)
     sumRows (rows, previousIndices) child = (allRows, ends childRanges)
       where
         separatorRows = contextRows (starts childRanges) previousIndices sources
@@ -220,12 +222,6 @@ textElements :: Range -> String -> [HTML]
 textElements range source = elementAndBreak Text =<< actualLines s
   where s = substring range source
 
-starts :: (Range , Range) -> (Int, Int)
-starts (left, right) = (start left, start right)
-
-ends :: (Range, Range) -> (Int, Int)
-ends (left, right) = (end left, end right)
-
 rowFromMaybeRows :: Maybe HTML -> Maybe HTML -> Row HTML
 rowFromMaybeRows a b = Row (maybe EmptyLine (Line False . (:[])) a) (maybe EmptyLine (Line False . (:[])) b)
 

From 03fcd995797ea21bbff6add4acf150895bdc1f4e Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 11:50:49 -0500
Subject: [PATCH 029/259] Generalize maybeLast to arbitrary Foldable.

---
 src/Split.hs | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index a8e5efb6d..3bd9a7af1 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -14,7 +14,6 @@ import Text.Blaze.Html5 hiding (map)
 import qualified Text.Blaze.Html5.Attributes as A
 import Text.Blaze.Html.Renderer.Utf8
 import qualified OrderedMap as Map
-import Data.Maybe
 import Data.Monoid
 import qualified Data.Set as Set
 import Data.List (intercalate)
@@ -225,8 +224,8 @@ textElements range source = elementAndBreak Text =<< actualLines s
 rowFromMaybeRows :: Maybe HTML -> Maybe HTML -> Row HTML
 rowFromMaybeRows a b = Row (maybe EmptyLine (Line False . (:[])) a) (maybe EmptyLine (Line False . (:[])) b)
 
-maybeLast :: [a] -> Maybe a
-maybeLast list = listToMaybe $ reverse list
+maybeLast :: Foldable f => f a -> Maybe a
+maybeLast = foldl (flip $ const . Just) Nothing
 
 adjoin2By :: (a -> Maybe a) -> [Row a] -> Row a -> [Row a]
 adjoin2By _ [] row = [row]

From e823fb6281e954280ca5bfd86ff23c5bd3f72034 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 12:22:20 -0500
Subject: [PATCH 030/259] Add a maybeLastIndex function over Range.

This is a better option than making Range Foldable at the moment.
---
 src/Range.hs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/Range.hs b/src/Range.hs
index e02451b34..1a6806b64 100644
--- a/src/Range.hs
+++ b/src/Range.hs
@@ -34,6 +34,9 @@ rangesAndWordsFrom startIndex string = maybe [] id $ takeAndContinue <$> (word <
     -- | > A member of one of the following Unicode general category _Letter_, _Mark_, _Number_, _Connector_Punctuation_
     isWord c = Char.isLetter c || Char.isNumber c || Char.isMark c || Char.generalCategory c == Char.ConnectorPunctuation
 
+maybeLastIndex :: Range -> Maybe Int
+maybeLastIndex (Range start end) | start == end = Nothing
+maybeLastIndex (Range _ end) = Just $ end - 1
 
 instance Ord Range where
   a <= b = start a <= start b

From 1e2c1979ee326133873c3bf0abdf783ff026ebb6 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 12:22:52 -0500
Subject: [PATCH 031/259] Document maybeLastIndex.

---
 src/Range.hs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/Range.hs b/src/Range.hs
index 1a6806b64..58dede3d1 100644
--- a/src/Range.hs
+++ b/src/Range.hs
@@ -34,6 +34,7 @@ rangesAndWordsFrom startIndex string = maybe [] id $ takeAndContinue <$> (word <
     -- | > A member of one of the following Unicode general category _Letter_, _Mark_, _Number_, _Connector_Punctuation_
     isWord c = Char.isLetter c || Char.isNumber c || Char.isMark c || Char.generalCategory c == Char.ConnectorPunctuation
 
+-- | Return Just the last index from a non-empty range, or if the range is empty, Nothing.
 maybeLastIndex :: Range -> Maybe Int
 maybeLastIndex (Range start end) | start == end = Nothing
 maybeLastIndex (Range _ end) = Just $ end - 1

From 7f1079e0ca2be980123314d69a18779b96793b91 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 12:23:21 -0500
Subject: [PATCH 032/259] Document Range.

---
 src/Range.hs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/Range.hs b/src/Range.hs
index 58dede3d1..55fa997a8 100644
--- a/src/Range.hs
+++ b/src/Range.hs
@@ -3,6 +3,7 @@ module Range where
 import Control.Applicative ((<|>))
 import qualified Data.Char as Char
 
+-- | A half-open interval of integers, defined by start & end indices.
 data Range = Range { start :: Int, end :: Int }
   deriving (Eq, Show)
 

From a4d30ec3ff297286a9a95350a36003b09dc51c8a Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 12:34:21 -0500
Subject: [PATCH 033/259] Add an openTerm function.

---
 src/Split.hs | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/Split.hs b/src/Split.hs
index 3bd9a7af1..68a85b11e 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -267,6 +267,11 @@ openElement (Dl _ elements) = openElement =<< maybeLast elements
 openElement (Div _ elements) = openElement =<< maybeLast elements
 openElement h = Just h
 
+openTerm :: String -> Term a Info -> Maybe (Term a Info)
+openTerm source term@(Info range _ :< _) = case (source !!) <$> maybeLastIndex range of
+  Just '\n' -> Just term
+  _ -> Nothing
+
 openLineBy :: (a -> Maybe a) -> [Line a] -> Maybe (Line a)
 openLineBy _ [] = Nothing
 openLineBy f (EmptyLine : rest) = openLineBy f rest

From 706e3c499a9a0242da7d60cec5e23b31d244abba Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 12:35:34 -0500
Subject: [PATCH 034/259] Generalize numberRows.

---
 src/Split.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index 68a85b11e..07407e3c7 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -72,7 +72,7 @@ split diff before after = return . renderHtml
 
     columnWidth = max (20 + digits maxNumber * 8) 40
 
-    numberRows :: [(Int, Line HTML, Int, Line HTML)] -> Row HTML -> [(Int, Line HTML, Int, Line HTML)]
+    numberRows :: [(Int, Line a, Int, Line a)] -> Row a -> [(Int, Line a, Int, Line a)]
     numberRows [] (Row EmptyLine EmptyLine) = []
     numberRows [] (Row left@(Line _ _) EmptyLine) = [(1, left, 0, EmptyLine)]
     numberRows [] (Row EmptyLine right@(Line _ _)) = [(0, EmptyLine, 1, right)]

From 3a159f1ae98863e856dc182234377f1acb288c45 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 12:39:36 -0500
Subject: [PATCH 035/259] rewrapLineContentsIn does not classify terms.

---
 src/Split.hs | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 07407e3c7..821f6b866 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -161,11 +161,11 @@ termToLines :: Term a Info -> String -> ([Line HTML], Range)
 termToLines (Info range categories :< syntax) source = (rows syntax, range)
   where
     rows (Leaf _) = reverse $ foldl (adjoin2LinesBy openElement) [] $ Line True . (:[]) <$> elements
-    rows (Indexed i) = rewrapLineContentsIn Ul <$> childLines i
-    rows (Fixed f) = rewrapLineContentsIn Ul <$> childLines f
-    rows (Keyed k) = rewrapLineContentsIn Dl <$> childLines k
+    rows (Indexed i) = rewrapLineContentsIn (Ul $ classify categories) <$> childLines i
+    rows (Fixed f) = rewrapLineContentsIn (Ul $ classify categories) <$> childLines f
+    rows (Keyed k) = rewrapLineContentsIn (Dl $ classify categories) <$> childLines k
 
-    rewrapLineContentsIn f (Line _ elements) = Line True [ f (classify categories) elements ]
+    rewrapLineContentsIn f (Line _ elements) = Line True [ f elements ]
     rewrapLineContentsIn _ EmptyLine = EmptyLine
     lineElements r s = Line True . (:[]) <$> textElements r s
     childLines i = appendRemainder $ foldl sumLines ([], start range) i

From cbf334481aa1ecf574566771c88f89ebfdc08222 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 12:48:54 -0500
Subject: [PATCH 036/259] Rename lineElements to contextLines.

---
 src/Split.hs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 821f6b866..968c775f8 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -167,12 +167,12 @@ termToLines (Info range categories :< syntax) source = (rows syntax, range)
 
     rewrapLineContentsIn f (Line _ elements) = Line True [ f elements ]
     rewrapLineContentsIn _ EmptyLine = EmptyLine
-    lineElements r s = Line True . (:[]) <$> textElements r s
+    contextLines r s = Line True . (:[]) <$> textElements r s
     childLines i = appendRemainder $ foldl sumLines ([], start range) i
-    appendRemainder (lines, previous) = reverse . foldl (adjoin2LinesBy openElement) [] $ lines ++ lineElements (Range previous (end range)) source
+    appendRemainder (lines, previous) = reverse . foldl (adjoin2LinesBy openElement) [] $ lines ++ contextLines (Range previous (end range)) source
     sumLines (lines, previous) child = (allLines, end childRange)
       where
-        separatorLines = lineElements (Range previous $ start childRange) source
+        separatorLines = contextLines (Range previous $ start childRange) source
         unadjoinedLines = lines ++ separatorLines ++ childLines
         allLines = reverse $ foldl (adjoin2LinesBy openElement) [] unadjoinedLines
         (childLines, childRange) = termToLines child source

From 66376d202a25c63d359023541e7d4d91e664ed0d Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 12:50:58 -0500
Subject: [PATCH 037/259] Tighten up the definition of childLines a little.

---
 src/Split.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 968c775f8..8b07efb2c 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -168,8 +168,8 @@ termToLines (Info range categories :< syntax) source = (rows syntax, range)
     rewrapLineContentsIn f (Line _ elements) = Line True [ f elements ]
     rewrapLineContentsIn _ EmptyLine = EmptyLine
     contextLines r s = Line True . (:[]) <$> textElements r s
-    childLines i = appendRemainder $ foldl sumLines ([], start range) i
-    appendRemainder (lines, previous) = reverse . foldl (adjoin2LinesBy openElement) [] $ lines ++ contextLines (Range previous (end range)) source
+    childLines i = let (lines, previous) = foldl sumLines ([], start range) i in
+      reverse . foldl (adjoin2LinesBy openElement) [] $ lines ++ contextLines (Range previous (end range)) source
     sumLines (lines, previous) child = (allLines, end childRange)
       where
         separatorLines = contextLines (Range previous $ start childRange) source

From ed6d6fffa128ae70dda1f0401ff41824b0024632 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 12:57:04 -0500
Subject: [PATCH 038/259] =?UTF-8?q?Rename=20adjoin2LinesBy=20=E2=86=92=20a?=
 =?UTF-8?q?djoinLinesBy.?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 src/Split.hs | 24 ++++++++++++------------
 1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 8b07efb2c..3f4825c8a 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -160,7 +160,7 @@ diffToRows (Pure (Replace a b)) _ before after = (replacedRows, (leftRange, righ
 termToLines :: Term a Info -> String -> ([Line HTML], Range)
 termToLines (Info range categories :< syntax) source = (rows syntax, range)
   where
-    rows (Leaf _) = reverse $ foldl (adjoin2LinesBy openElement) [] $ Line True . (:[]) <$> elements
+    rows (Leaf _) = reverse $ foldl (adjoinLinesBy openElement) [] $ Line True . (:[]) <$> elements
     rows (Indexed i) = rewrapLineContentsIn (Ul $ classify categories) <$> childLines i
     rows (Fixed f) = rewrapLineContentsIn (Ul $ classify categories) <$> childLines f
     rows (Keyed k) = rewrapLineContentsIn (Dl $ classify categories) <$> childLines k
@@ -169,12 +169,12 @@ termToLines (Info range categories :< syntax) source = (rows syntax, range)
     rewrapLineContentsIn _ EmptyLine = EmptyLine
     contextLines r s = Line True . (:[]) <$> textElements r s
     childLines i = let (lines, previous) = foldl sumLines ([], start range) i in
-      reverse . foldl (adjoin2LinesBy openElement) [] $ lines ++ contextLines (Range previous (end range)) source
+      reverse . foldl (adjoinLinesBy openElement) [] $ lines ++ contextLines (Range previous (end range)) source
     sumLines (lines, previous) child = (allLines, end childRange)
       where
         separatorLines = contextLines (Range previous $ start childRange) source
         unadjoinedLines = lines ++ separatorLines ++ childLines
-        allLines = reverse $ foldl (adjoin2LinesBy openElement) [] unadjoinedLines
+        allLines = reverse $ foldl (adjoinLinesBy openElement) [] unadjoinedLines
         (childLines, childRange) = termToLines child source
     elements = elementAndBreak (Span $ classify categories) =<< actualLines (substring range source)
 
@@ -231,14 +231,14 @@ adjoin2By :: (a -> Maybe a) -> [Row a] -> Row a -> [Row a]
 adjoin2By _ [] row = [row]
 
 adjoin2By f rows (Row left' right') | Just _ <- openLineBy f $ leftLines rows, Just _ <- openLineBy f $ rightLines rows = zipWith Row lefts rights
-  where lefts = adjoin2LinesBy f (leftLines rows) left'
-        rights = adjoin2LinesBy f (rightLines rows) right'
+  where lefts = adjoinLinesBy f (leftLines rows) left'
+        rights = adjoinLinesBy f (rightLines rows) right'
 
 adjoin2By f rows (Row left' right') | Just _ <- openLineBy f $ leftLines rows = case right' of
   EmptyLine -> rest
   _ -> Row EmptyLine right' : rest
   where rest = zipWith Row lefts rights
-        lefts = adjoin2LinesBy f (leftLines rows) left'
+        lefts = adjoinLinesBy f (leftLines rows) left'
         rights = rightLines rows
 
 adjoin2By f rows (Row left' right') | Just _ <- openLineBy f $ rightLines rows = case left' of
@@ -246,7 +246,7 @@ adjoin2By f rows (Row left' right') | Just _ <- openLineBy f $ rightLines rows =
   _ -> Row left' EmptyLine : rest
   where rest = zipWith Row lefts rights
         lefts = leftLines rows
-        rights = adjoin2LinesBy f (rightLines rows) right'
+        rights = adjoinLinesBy f (rightLines rows) right'
 
 adjoin2By _ rows row = row : rows
 
@@ -277,11 +277,11 @@ openLineBy _ [] = Nothing
 openLineBy f (EmptyLine : rest) = openLineBy f rest
 openLineBy f (line : _) = const line <$> (f =<< maybeLast (unLine line))
 
-adjoin2LinesBy :: (a -> Maybe a) -> [Line a] -> Line a -> [Line a]
-adjoin2LinesBy _ [] line = [line]
-adjoin2LinesBy f (EmptyLine : xs) line | Just _ <- openLineBy f xs = EmptyLine : adjoin2LinesBy f xs line
-adjoin2LinesBy f (prev:rest) line | Just _ <- openLineBy f [ prev ] = (prev <> line) : rest
-adjoin2LinesBy _ lines line = line : lines
+adjoinLinesBy :: (a -> Maybe a) -> [Line a] -> Line a -> [Line a]
+adjoinLinesBy _ [] line = [line]
+adjoinLinesBy f (EmptyLine : xs) line | Just _ <- openLineBy f xs = EmptyLine : adjoinLinesBy f xs line
+adjoinLinesBy f (prev:rest) line | Just _ <- openLineBy f [ prev ] = (prev <> line) : rest
+adjoinLinesBy _ lines line = line : lines
 
 zipWithMaybe :: (Maybe a -> Maybe b -> c) -> [a] -> [b] -> [c]
 zipWithMaybe f la lb = take len $ zipWith f la' lb'

From d4cfb276a45c2277080876a6d6de8d3cfb530bd9 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 12:57:11 -0500
Subject: [PATCH 039/259] =?UTF-8?q?Rename=20adjoin2By=20=E2=86=92=20adjoin?=
 =?UTF-8?q?By.?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 src/Split.hs      | 14 +++++++-------
 test/SplitSpec.hs | 12 ++++++------
 2 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 3f4825c8a..986f1452d 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -196,7 +196,7 @@ annotatedToRows (Annotated (Info left leftCategories, Info right rightCategories
     ranges = (left, right)
     sources = (before, after)
     childRows = appendRemainder . foldl sumRows ([], starts ranges)
-    appendRemainder (rows, previousIndices) = reverse . foldl (adjoin2By openElement) [] $ rows ++ contextRows (ends ranges) previousIndices sources
+    appendRemainder (rows, previousIndices) = reverse . foldl (adjoinBy openElement) [] $ rows ++ contextRows (ends ranges) previousIndices sources
     starts (left, right) = (start left, start right)
     ends (left, right) = (end left, end right)
     sumRows (rows, previousIndices) child = (allRows, ends childRanges)
@@ -227,28 +227,28 @@ rowFromMaybeRows a b = Row (maybe EmptyLine (Line False . (:[])) a) (maybe Empty
 maybeLast :: Foldable f => f a -> Maybe a
 maybeLast = foldl (flip $ const . Just) Nothing
 
-adjoin2By :: (a -> Maybe a) -> [Row a] -> Row a -> [Row a]
-adjoin2By _ [] row = [row]
+adjoinBy :: (a -> Maybe a) -> [Row a] -> Row a -> [Row a]
+adjoinBy _ [] row = [row]
 
-adjoin2By f rows (Row left' right') | Just _ <- openLineBy f $ leftLines rows, Just _ <- openLineBy f $ rightLines rows = zipWith Row lefts rights
+adjoinBy f rows (Row left' right') | Just _ <- openLineBy f $ leftLines rows, Just _ <- openLineBy f $ rightLines rows = zipWith Row lefts rights
   where lefts = adjoinLinesBy f (leftLines rows) left'
         rights = adjoinLinesBy f (rightLines rows) right'
 
-adjoin2By f rows (Row left' right') | Just _ <- openLineBy f $ leftLines rows = case right' of
+adjoinBy f rows (Row left' right') | Just _ <- openLineBy f $ leftLines rows = case right' of
   EmptyLine -> rest
   _ -> Row EmptyLine right' : rest
   where rest = zipWith Row lefts rights
         lefts = adjoinLinesBy f (leftLines rows) left'
         rights = rightLines rows
 
-adjoin2By f rows (Row left' right') | Just _ <- openLineBy f $ rightLines rows = case left' of
+adjoinBy f rows (Row left' right') | Just _ <- openLineBy f $ rightLines rows = case left' of
   EmptyLine -> rest
   _ -> Row left' EmptyLine : rest
   where rest = zipWith Row lefts rights
         lefts = leftLines rows
         rights = adjoinLinesBy f (rightLines rows) right'
 
-adjoin2By _ rows row = row : rows
+adjoinBy _ rows row = row : rows
 
 leftLines :: [Row a] -> [Line a]
 leftLines rows = left <$> rows
diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 898849971..315ad56bb 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -112,26 +112,26 @@ spec = do
             ([ Row (Line False [ span "t\776" ]) (Line False [ span "\7831"]) ], (Range 0 2, Range 0 1))
 
 
-  describe "adjoin2By" $ do
+  describe "adjoinBy" $ do
     prop "is identity on top of no rows" $
-      \ a -> adjoin2By openElement [] a == [ a ]
+      \ a -> adjoinBy openElement [] a == [ a ]
 
     prop "appends onto open rows" $
       forAll ((arbitrary `suchThat` isOpen) >>= \ a -> ((,) a) <$> (arbitrary `suchThat` isOpen)) $
         \ (a@(Row (Line ac1 as1) (Line bc1 bs1)), b@(Row (Line ac2 as2) (Line bc2 bs2))) ->
-          adjoin2By openElement [ a ] b `shouldBe` [ Row (Line (ac1 || ac2) $ as1 ++ as2) (Line (bc1 || bc2) $ bs1 ++ bs2) ]
+          adjoinBy openElement [ a ] b `shouldBe` [ Row (Line (ac1 || ac2) $ as1 ++ as2) (Line (bc1 || bc2) $ bs1 ++ bs2) ]
 
     prop "does not append onto closed rows" $
       forAll ((arbitrary `suchThat` isClosed) >>= \ a -> ((,) a) <$> (arbitrary `suchThat` isClosed)) $
-        \ (a, b) -> adjoin2By openElement [ a ] b `shouldBe` [ b, a ]
+        \ (a, b) -> adjoinBy openElement [ a ] b `shouldBe` [ b, a ]
 
     prop "does not promote elements through empty lines onto closed lines" $
       forAll ((arbitrary `suchThat` isClosed) >>= \ a -> ((,) a) <$> (arbitrary `suchThat` isClosed)) $
-        \ (a, b) -> adjoin2By openElement [ Row EmptyLine EmptyLine, a ] b `shouldBe` [ b, Row EmptyLine EmptyLine, a ]
+        \ (a, b) -> adjoinBy openElement [ Row EmptyLine EmptyLine, a ] b `shouldBe` [ b, Row EmptyLine EmptyLine, a ]
 
     prop "promotes elements through empty lines onto open lines" $
       forAll ((arbitrary `suchThat` isOpen) >>= \ a -> ((,) a) <$> (arbitrary `suchThat` isOpen)) $
-        \ (a, b) -> adjoin2By openElement [ Row EmptyLine EmptyLine, a ] b `shouldBe` Row EmptyLine EmptyLine : adjoin2By openElement [ a ] b
+        \ (a, b) -> adjoinBy openElement [ Row EmptyLine EmptyLine, a ] b `shouldBe` Row EmptyLine EmptyLine : adjoinBy openElement [ a ] b
 
   describe "termToLines" $ do
     it "splits multi-line terms into multiple lines" $

From 64362581c4f324ea2f581ee27fc895f39916e6ca Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 12:57:50 -0500
Subject: [PATCH 040/259] =?UTF-8?q?Rename=20adjoinBy=20=E2=86=92=20adjoinR?=
 =?UTF-8?q?owsBy.?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 src/Split.hs      | 14 +++++++-------
 test/SplitSpec.hs | 12 ++++++------
 2 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 986f1452d..9c77e4d41 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -196,7 +196,7 @@ annotatedToRows (Annotated (Info left leftCategories, Info right rightCategories
     ranges = (left, right)
     sources = (before, after)
     childRows = appendRemainder . foldl sumRows ([], starts ranges)
-    appendRemainder (rows, previousIndices) = reverse . foldl (adjoinBy openElement) [] $ rows ++ contextRows (ends ranges) previousIndices sources
+    appendRemainder (rows, previousIndices) = reverse . foldl (adjoinRowsBy openElement) [] $ rows ++ contextRows (ends ranges) previousIndices sources
     starts (left, right) = (start left, start right)
     ends (left, right) = (end left, end right)
     sumRows (rows, previousIndices) child = (allRows, ends childRanges)
@@ -227,28 +227,28 @@ rowFromMaybeRows a b = Row (maybe EmptyLine (Line False . (:[])) a) (maybe Empty
 maybeLast :: Foldable f => f a -> Maybe a
 maybeLast = foldl (flip $ const . Just) Nothing
 
-adjoinBy :: (a -> Maybe a) -> [Row a] -> Row a -> [Row a]
-adjoinBy _ [] row = [row]
+adjoinRowsBy :: (a -> Maybe a) -> [Row a] -> Row a -> [Row a]
+adjoinRowsBy _ [] row = [row]
 
-adjoinBy f rows (Row left' right') | Just _ <- openLineBy f $ leftLines rows, Just _ <- openLineBy f $ rightLines rows = zipWith Row lefts rights
+adjoinRowsBy f rows (Row left' right') | Just _ <- openLineBy f $ leftLines rows, Just _ <- openLineBy f $ rightLines rows = zipWith Row lefts rights
   where lefts = adjoinLinesBy f (leftLines rows) left'
         rights = adjoinLinesBy f (rightLines rows) right'
 
-adjoinBy f rows (Row left' right') | Just _ <- openLineBy f $ leftLines rows = case right' of
+adjoinRowsBy f rows (Row left' right') | Just _ <- openLineBy f $ leftLines rows = case right' of
   EmptyLine -> rest
   _ -> Row EmptyLine right' : rest
   where rest = zipWith Row lefts rights
         lefts = adjoinLinesBy f (leftLines rows) left'
         rights = rightLines rows
 
-adjoinBy f rows (Row left' right') | Just _ <- openLineBy f $ rightLines rows = case left' of
+adjoinRowsBy f rows (Row left' right') | Just _ <- openLineBy f $ rightLines rows = case left' of
   EmptyLine -> rest
   _ -> Row left' EmptyLine : rest
   where rest = zipWith Row lefts rights
         lefts = leftLines rows
         rights = adjoinLinesBy f (rightLines rows) right'
 
-adjoinBy _ rows row = row : rows
+adjoinRowsBy _ rows row = row : rows
 
 leftLines :: [Row a] -> [Line a]
 leftLines rows = left <$> rows
diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 315ad56bb..56a5bd7f6 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -112,26 +112,26 @@ spec = do
             ([ Row (Line False [ span "t\776" ]) (Line False [ span "\7831"]) ], (Range 0 2, Range 0 1))
 
 
-  describe "adjoinBy" $ do
+  describe "adjoinRowsBy" $ do
     prop "is identity on top of no rows" $
-      \ a -> adjoinBy openElement [] a == [ a ]
+      \ a -> adjoinRowsBy openElement [] a == [ a ]
 
     prop "appends onto open rows" $
       forAll ((arbitrary `suchThat` isOpen) >>= \ a -> ((,) a) <$> (arbitrary `suchThat` isOpen)) $
         \ (a@(Row (Line ac1 as1) (Line bc1 bs1)), b@(Row (Line ac2 as2) (Line bc2 bs2))) ->
-          adjoinBy openElement [ a ] b `shouldBe` [ Row (Line (ac1 || ac2) $ as1 ++ as2) (Line (bc1 || bc2) $ bs1 ++ bs2) ]
+          adjoinRowsBy openElement [ a ] b `shouldBe` [ Row (Line (ac1 || ac2) $ as1 ++ as2) (Line (bc1 || bc2) $ bs1 ++ bs2) ]
 
     prop "does not append onto closed rows" $
       forAll ((arbitrary `suchThat` isClosed) >>= \ a -> ((,) a) <$> (arbitrary `suchThat` isClosed)) $
-        \ (a, b) -> adjoinBy openElement [ a ] b `shouldBe` [ b, a ]
+        \ (a, b) -> adjoinRowsBy openElement [ a ] b `shouldBe` [ b, a ]
 
     prop "does not promote elements through empty lines onto closed lines" $
       forAll ((arbitrary `suchThat` isClosed) >>= \ a -> ((,) a) <$> (arbitrary `suchThat` isClosed)) $
-        \ (a, b) -> adjoinBy openElement [ Row EmptyLine EmptyLine, a ] b `shouldBe` [ b, Row EmptyLine EmptyLine, a ]
+        \ (a, b) -> adjoinRowsBy openElement [ Row EmptyLine EmptyLine, a ] b `shouldBe` [ b, Row EmptyLine EmptyLine, a ]
 
     prop "promotes elements through empty lines onto open lines" $
       forAll ((arbitrary `suchThat` isOpen) >>= \ a -> ((,) a) <$> (arbitrary `suchThat` isOpen)) $
-        \ (a, b) -> adjoinBy openElement [ Row EmptyLine EmptyLine, a ] b `shouldBe` Row EmptyLine EmptyLine : adjoinBy openElement [ a ] b
+        \ (a, b) -> adjoinRowsBy openElement [ Row EmptyLine EmptyLine, a ] b `shouldBe` Row EmptyLine EmptyLine : adjoinRowsBy openElement [ a ] b
 
   describe "termToLines" $ do
     it "splits multi-line terms into multiple lines" $

From 3c85d4d0aff404987223e4c610c761c55277b62e Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 13:00:46 -0500
Subject: [PATCH 041/259] =?UTF-8?q?Use=20Data.Maybe=E2=80=99s=20isJust=20&?=
 =?UTF-8?q?=20isNothing=20to=20test=20for=20open=20elements.?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 test/SplitSpec.hs | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 56a5bd7f6..fa02a3be9 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -9,6 +9,7 @@ import Test.Hspec.QuickCheck
 import Test.QuickCheck hiding (Fixed)
 import Control.Comonad.Cofree
 import Control.Monad.Free hiding (unfold)
+import qualified Data.Maybe as Maybe
 import Patch
 import Syntax
 
@@ -167,6 +168,6 @@ spec = do
       offsetInfo by (Info (Range start end) categories) = Info (Range (start + by) (end + by)) categories
       offsetAnnotated by1 by2 (Annotated (left, right) syntax) = Annotated (offsetInfo by1 left, offsetInfo by2 right) syntax
       span = Span (Just "category-leaf")
-      isOpen (Row a b) = (maybe False (const True) $ openLineBy openElement [ a ]) && (maybe False (const True) $ openLineBy openElement [ b ])
-      isClosed (Row a@(Line _ _) b@(Line _ _)) = (maybe True (const False) $ openLineBy openElement [ a ]) && (maybe True (const False) $ openLineBy openElement [ b ])
+      isOpen (Row a b) = (Maybe.isJust $ openLineBy openElement [ a ]) && (Maybe.isJust $ openLineBy openElement [ b ])
+      isClosed (Row a@(Line _ _) b@(Line _ _)) = (Maybe.isNothing $ openLineBy openElement [ a ]) && (Maybe.isNothing $ openLineBy openElement [ b ])
       isClosed (Row _ _) = False

From c0a566be4af465c038e35e90d145c1d4d1009a8b Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 13:01:38 -0500
Subject: [PATCH 042/259] Eta-reduce the definition of `unchanged`.

---
 test/SplitSpec.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index fa02a3be9..b59d4048b 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -163,7 +163,7 @@ spec = do
       leftRow xs = Row (Line False xs) EmptyLine
       rowText a b = Row (Line False [ Text a ]) (Line False [ Text b ])
       info source category = Info (totalRange source)  (Set.fromList [ category ])
-      unchanged source category = formatted source source category
+      unchanged source = formatted source source
       formatted source1 source2 category = Annotated (info source1 category, info source2 category)
       offsetInfo by (Info (Range start end) categories) = Info (Range (start + by) (end + by)) categories
       offsetAnnotated by1 by2 (Annotated (left, right) syntax) = Annotated (offsetInfo by1 left, offsetInfo by2 right) syntax

From 671904cf61441bde52ce3a62ce8475dd378e3f60 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 13:01:46 -0500
Subject: [PATCH 043/259] Remove redundant parentheses.

---
 test/SplitSpec.hs | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index b59d4048b..9df882307 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -95,7 +95,7 @@ spec = do
     it "should split multi-line deletions across multiple rows" $
       let (sourceA, sourceB) = ("/*\n*/\na", "a") in
         annotatedToRows (formatted sourceA sourceB "branch" (Indexed [
-          Pure . Delete $ (Info (Range 0 5) (Set.fromList ["leaf"]) :< (Leaf "")),
+          Pure . Delete $ (Info (Range 0 5) (Set.fromList ["leaf"]) :< Leaf ""),
           Free . offsetAnnotated 6 0 $ unchanged "a" "leaf" (Leaf "")
         ])) sourceA sourceB `shouldBe`
         ([
@@ -107,7 +107,7 @@ spec = do
     describe "unicode" $
       it "equivalent precomposed and decomposed characters are not equal" $
         let (sourceA, sourceB) = ("t\776", "\7831")
-            syntax = Leaf . Pure $ Replace (info sourceA "leaf" :< (Leaf "")) (info sourceB "leaf" :< (Leaf ""))
+            syntax = Leaf . Pure $ Replace (info sourceA "leaf" :< Leaf "") (info sourceB "leaf" :< Leaf "")
         in
             annotatedToRows (formatted sourceA sourceB "leaf" syntax) sourceA sourceB `shouldBe`
             ([ Row (Line False [ span "t\776" ]) (Line False [ span "\7831"]) ], (Range 0 2, Range 0 1))
@@ -118,25 +118,25 @@ spec = do
       \ a -> adjoinRowsBy openElement [] a == [ a ]
 
     prop "appends onto open rows" $
-      forAll ((arbitrary `suchThat` isOpen) >>= \ a -> ((,) a) <$> (arbitrary `suchThat` isOpen)) $
+      forAll ((arbitrary `suchThat` isOpen) >>= \ a -> (,) a <$> (arbitrary `suchThat` isOpen)) $
         \ (a@(Row (Line ac1 as1) (Line bc1 bs1)), b@(Row (Line ac2 as2) (Line bc2 bs2))) ->
           adjoinRowsBy openElement [ a ] b `shouldBe` [ Row (Line (ac1 || ac2) $ as1 ++ as2) (Line (bc1 || bc2) $ bs1 ++ bs2) ]
 
     prop "does not append onto closed rows" $
-      forAll ((arbitrary `suchThat` isClosed) >>= \ a -> ((,) a) <$> (arbitrary `suchThat` isClosed)) $
+      forAll ((arbitrary `suchThat` isClosed) >>= \ a -> (,) a <$> (arbitrary `suchThat` isClosed)) $
         \ (a, b) -> adjoinRowsBy openElement [ a ] b `shouldBe` [ b, a ]
 
     prop "does not promote elements through empty lines onto closed lines" $
-      forAll ((arbitrary `suchThat` isClosed) >>= \ a -> ((,) a) <$> (arbitrary `suchThat` isClosed)) $
+      forAll ((arbitrary `suchThat` isClosed) >>= \ a -> (,) a <$> (arbitrary `suchThat` isClosed)) $
         \ (a, b) -> adjoinRowsBy openElement [ Row EmptyLine EmptyLine, a ] b `shouldBe` [ b, Row EmptyLine EmptyLine, a ]
 
     prop "promotes elements through empty lines onto open lines" $
-      forAll ((arbitrary `suchThat` isOpen) >>= \ a -> ((,) a) <$> (arbitrary `suchThat` isOpen)) $
+      forAll ((arbitrary `suchThat` isOpen) >>= \ a -> (,) a <$> (arbitrary `suchThat` isOpen)) $
         \ (a, b) -> adjoinRowsBy openElement [ Row EmptyLine EmptyLine, a ] b `shouldBe` Row EmptyLine EmptyLine : adjoinRowsBy openElement [ a ] b
 
   describe "termToLines" $ do
     it "splits multi-line terms into multiple lines" $
-      termToLines (Info (Range 0 5) (Set.singleton "leaf") :< (Leaf "")) "/*\n*/"
+      termToLines (Info (Range 0 5) (Set.singleton "leaf") :< Leaf "") "/*\n*/"
       `shouldBe`
       ([
         Line True [ span "/*", Break ],

From cbc1240946583547bfad8a5041ed257a78f7df39 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 13:03:08 -0500
Subject: [PATCH 044/259] Avoid needless $s.

---
 test/SplitSpec.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 9df882307..f462dec0a 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -168,6 +168,6 @@ spec = do
       offsetInfo by (Info (Range start end) categories) = Info (Range (start + by) (end + by)) categories
       offsetAnnotated by1 by2 (Annotated (left, right) syntax) = Annotated (offsetInfo by1 left, offsetInfo by2 right) syntax
       span = Span (Just "category-leaf")
-      isOpen (Row a b) = (Maybe.isJust $ openLineBy openElement [ a ]) && (Maybe.isJust $ openLineBy openElement [ b ])
-      isClosed (Row a@(Line _ _) b@(Line _ _)) = (Maybe.isNothing $ openLineBy openElement [ a ]) && (Maybe.isNothing $ openLineBy openElement [ b ])
+      isOpen (Row a b) = Maybe.isJust (openLineBy openElement [ a ]) && Maybe.isJust (openLineBy openElement [ b ])
+      isClosed (Row a@(Line _ _) b@(Line _ _)) = Maybe.isNothing (openLineBy openElement [ a ]) && Maybe.isNothing (openLineBy openElement [ b ])
       isClosed (Row _ _) = False

From b351f1b29dbdb8fbe083433bae5df13908753870 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 13:10:11 -0500
Subject: [PATCH 045/259] Generalize rowFromMaybeRows.

---
 src/Split.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index 9c77e4d41..b740b2135 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -221,7 +221,7 @@ textElements :: Range -> String -> [HTML]
 textElements range source = elementAndBreak Text =<< actualLines s
   where s = substring range source
 
-rowFromMaybeRows :: Maybe HTML -> Maybe HTML -> Row HTML
+rowFromMaybeRows :: Maybe a -> Maybe a -> Row a
 rowFromMaybeRows a b = Row (maybe EmptyLine (Line False . (:[])) a) (maybe EmptyLine (Line False . (:[])) b)
 
 maybeLast :: Foldable f => f a -> Maybe a

From ea161cdd4a48c5c393d47a41a93f921fc841cdba Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 13:11:01 -0500
Subject: [PATCH 046/259] Generalize the other rowFromMaybeRows.

---
 src/Split.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index b740b2135..71e022c98 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -150,7 +150,7 @@ diffToRows (Pure (Replace a b)) _ before after = (replacedRows, (leftRange, righ
   where
     replacedRows = zipWithMaybe rowFromMaybeRows (replace <$> leftElements) (replace <$> rightElements)
     replace = (:[]) . Div (Just "replace") . unLine
-    rowFromMaybeRows :: Maybe [HTML] -> Maybe [HTML] -> Row HTML
+    rowFromMaybeRows :: Maybe [a] -> Maybe [a] -> Row a
     rowFromMaybeRows a b = Row (maybe EmptyLine (Line True) a) (maybe EmptyLine (Line True) b)
     (leftElements, leftRange) = termToLines a before
     (rightElements, rightRange) = termToLines b after

From 2c703b30e40f84f73845e7840f2eb53f908f3dd7 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 13:12:35 -0500
Subject: [PATCH 047/259] Remove the inner rowFromMaybeRows.

---
 src/Split.hs | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 71e022c98..0f3a9c4b6 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -149,9 +149,7 @@ diffToRows (Pure (Delete term)) (_, previousIndex) before _ = (rowWithDeletedLin
 diffToRows (Pure (Replace a b)) _ before after = (replacedRows, (leftRange, rightRange))
   where
     replacedRows = zipWithMaybe rowFromMaybeRows (replace <$> leftElements) (replace <$> rightElements)
-    replace = (:[]) . Div (Just "replace") . unLine
-    rowFromMaybeRows :: Maybe [a] -> Maybe [a] -> Row a
-    rowFromMaybeRows a b = Row (maybe EmptyLine (Line True) a) (maybe EmptyLine (Line True) b)
+    replace = Div (Just "replace") . unLine
     (leftElements, leftRange) = termToLines a before
     (rightElements, rightRange) = termToLines b after
 

From 568df9937b7678bde5744fd795cee687e14b624b Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 13:15:37 -0500
Subject: [PATCH 048/259] Define `classify` in terms of maybeLast.

---
 src/Split.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index 0f3a9c4b6..1c0419d06 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -289,7 +289,7 @@ zipWithMaybe f la lb = take len $ zipWith f la' lb'
     lb' = (Just <$> lb) ++ repeat Nothing
 
 classify :: Set.Set Category -> Maybe ClassName
-classify = foldr (const . Just . ("category-" ++)) Nothing
+classify categories = ("category-" ++) <$> maybeLast categories
 
 actualLines :: String -> [String]
 actualLines "" = [""]

From 693028f70c40d9bf4d4c7cc10c736af93b1007be Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 13:18:41 -0500
Subject: [PATCH 049/259] Define field accessors for the left & right lines in
 a Row.

---
 src/Split.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index 1c0419d06..6ba67cb22 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -83,7 +83,7 @@ split diff before after = return . renderHtml
     numberRows rows@((leftCount, _, rightCount, _):_) (Row left right) = (leftCount + 1, left, rightCount + 1, right):rows
 
 
-data Row a = Row (Line a) (Line a)
+data Row a = Row { unLeft :: Line a, unRight :: Line a }
   deriving Eq
 
 instance Show a => Show (Row a) where

From 71ca4fc147c4e54b4490f76cfa3aeae23ebafc3c Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 13:19:45 -0500
Subject: [PATCH 050/259] Define leftLines in terms of unLeft.

---
 src/Split.hs | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 6ba67cb22..0ba59d5ca 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -249,9 +249,7 @@ adjoinRowsBy f rows (Row left' right') | Just _ <- openLineBy f $ rightLines row
 adjoinRowsBy _ rows row = row : rows
 
 leftLines :: [Row a] -> [Line a]
-leftLines rows = left <$> rows
-  where
-    left (Row left _) = left
+leftLines rows = unLeft <$> rows
 
 rightLines :: [Row a] -> [Line a]
 rightLines rows = right <$> rows

From 6e76f3e6187a81e07737c50cf764bc34454433c2 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 13:19:51 -0500
Subject: [PATCH 051/259] Define rightLines in terms of unRight.

---
 src/Split.hs | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 0ba59d5ca..651527c3b 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -252,9 +252,7 @@ leftLines :: [Row a] -> [Line a]
 leftLines rows = unLeft <$> rows
 
 rightLines :: [Row a] -> [Line a]
-rightLines rows = right <$> rows
-  where
-    right (Row _ right) = right
+rightLines rows = unRight <$> rows
 
 openElement :: HTML -> Maybe HTML
 openElement Break = Nothing

From 7b0ea6678e5f919e151be701fd917663e833ca5a Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 13:20:47 -0500
Subject: [PATCH 052/259] fmap unLeft over rows directly.

---
 src/Split.hs | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 651527c3b..daaa5775b 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -228,22 +228,22 @@ maybeLast = foldl (flip $ const . Just) Nothing
 adjoinRowsBy :: (a -> Maybe a) -> [Row a] -> Row a -> [Row a]
 adjoinRowsBy _ [] row = [row]
 
-adjoinRowsBy f rows (Row left' right') | Just _ <- openLineBy f $ leftLines rows, Just _ <- openLineBy f $ rightLines rows = zipWith Row lefts rights
-  where lefts = adjoinLinesBy f (leftLines rows) left'
+adjoinRowsBy f rows (Row left' right') | Just _ <- openLineBy f $ unLeft <$> rows, Just _ <- openLineBy f $ rightLines rows = zipWith Row lefts rights
+  where lefts = adjoinLinesBy f (unLeft <$> rows) left'
         rights = adjoinLinesBy f (rightLines rows) right'
 
-adjoinRowsBy f rows (Row left' right') | Just _ <- openLineBy f $ leftLines rows = case right' of
+adjoinRowsBy f rows (Row left' right') | Just _ <- openLineBy f $ unLeft <$> rows = case right' of
   EmptyLine -> rest
   _ -> Row EmptyLine right' : rest
   where rest = zipWith Row lefts rights
-        lefts = adjoinLinesBy f (leftLines rows) left'
+        lefts = adjoinLinesBy f (unLeft <$> rows) left'
         rights = rightLines rows
 
 adjoinRowsBy f rows (Row left' right') | Just _ <- openLineBy f $ rightLines rows = case left' of
   EmptyLine -> rest
   _ -> Row left' EmptyLine : rest
   where rest = zipWith Row lefts rights
-        lefts = leftLines rows
+        lefts = unLeft <$> rows
         rights = adjoinLinesBy f (rightLines rows) right'
 
 adjoinRowsBy _ rows row = row : rows

From 2b5712cd58d8bc0b4ac5b0036aab260812b26331 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 13:21:09 -0500
Subject: [PATCH 053/259] fmap unRight over rows directly.

---
 src/Split.hs | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index daaa5775b..a5d352070 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -228,23 +228,23 @@ maybeLast = foldl (flip $ const . Just) Nothing
 adjoinRowsBy :: (a -> Maybe a) -> [Row a] -> Row a -> [Row a]
 adjoinRowsBy _ [] row = [row]
 
-adjoinRowsBy f rows (Row left' right') | Just _ <- openLineBy f $ unLeft <$> rows, Just _ <- openLineBy f $ rightLines rows = zipWith Row lefts rights
+adjoinRowsBy f rows (Row left' right') | Just _ <- openLineBy f $ unLeft <$> rows, Just _ <- openLineBy f $ unRight <$> rows = zipWith Row lefts rights
   where lefts = adjoinLinesBy f (unLeft <$> rows) left'
-        rights = adjoinLinesBy f (rightLines rows) right'
+        rights = adjoinLinesBy f (unRight <$> rows) right'
 
 adjoinRowsBy f rows (Row left' right') | Just _ <- openLineBy f $ unLeft <$> rows = case right' of
   EmptyLine -> rest
   _ -> Row EmptyLine right' : rest
   where rest = zipWith Row lefts rights
         lefts = adjoinLinesBy f (unLeft <$> rows) left'
-        rights = rightLines rows
+        rights = unRight <$> rows
 
-adjoinRowsBy f rows (Row left' right') | Just _ <- openLineBy f $ rightLines rows = case left' of
+adjoinRowsBy f rows (Row left' right') | Just _ <- openLineBy f $ unRight <$> rows = case left' of
   EmptyLine -> rest
   _ -> Row left' EmptyLine : rest
   where rest = zipWith Row lefts rights
         lefts = unLeft <$> rows
-        rights = adjoinLinesBy f (rightLines rows) right'
+        rights = adjoinLinesBy f (unRight <$> rows) right'
 
 adjoinRowsBy _ rows row = row : rows
 

From d38f94df8ccc79b9e9a7f9c56f97d83f1ae1b42c Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 13:21:23 -0500
Subject: [PATCH 054/259] Remove leftLines.

---
 src/Split.hs | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index a5d352070..0c1ced863 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -248,9 +248,6 @@ adjoinRowsBy f rows (Row left' right') | Just _ <- openLineBy f $ unRight <$> ro
 
 adjoinRowsBy _ rows row = row : rows
 
-leftLines :: [Row a] -> [Line a]
-leftLines rows = unLeft <$> rows
-
 rightLines :: [Row a] -> [Line a]
 rightLines rows = unRight <$> rows
 

From fc819fb48d5cbbc912dbfe6fa7b784990cc2d5f1 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 13:21:31 -0500
Subject: [PATCH 055/259] Remove rightLines.

---
 src/Split.hs | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 0c1ced863..03e74efd0 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -248,9 +248,6 @@ adjoinRowsBy f rows (Row left' right') | Just _ <- openLineBy f $ unRight <$> ro
 
 adjoinRowsBy _ rows row = row : rows
 
-rightLines :: [Row a] -> [Line a]
-rightLines rows = unRight <$> rows
-
 openElement :: HTML -> Maybe HTML
 openElement Break = Nothing
 openElement (Ul _ elements) = openElement =<< maybeLast elements

From b857464c44249fc1b90f82c154dd0adb364788a5 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 13:25:32 -0500
Subject: [PATCH 056/259] Reformat a comment.

---
 src/Split.hs | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 03e74efd0..348a4f687 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -153,8 +153,7 @@ diffToRows (Pure (Replace a b)) _ before after = (replacedRows, (leftRange, righ
     (leftElements, leftRange) = termToLines a before
     (rightElements, rightRange) = termToLines b after
 
--- | Takes a term and a `source` and returns a list of HTML lines
--- | and their range within `source`.
+-- | Takes a term and a `source` and returns a list of lines and their range within `source`.
 termToLines :: Term a Info -> String -> ([Line HTML], Range)
 termToLines (Info range categories :< syntax) source = (rows syntax, range)
   where

From cefbdd400e77d0b7646a6a722057a96e3537059a Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 13:26:51 -0500
Subject: [PATCH 057/259] Simplify mappend over Lines.

---
 src/Split.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 348a4f687..029cff002 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -126,8 +126,8 @@ instance Show a => Show (Line a) where
 instance Monoid (Line a) where
  mempty = EmptyLine
  mappend EmptyLine EmptyLine = EmptyLine
- mappend EmptyLine (Line c ys) = Line c ys
- mappend (Line c xs) EmptyLine = Line c xs
+ mappend EmptyLine line = line
+ mappend line EmptyLine = line
  mappend (Line c1 xs) (Line c2 ys) = Line (c1 || c2) (xs <> ys)
 
 instance Monoid (Row a) where

From ce5911b9b6ee1f98fb99c926b4534317ea0c6b99 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 13:26:59 -0500
Subject: [PATCH 058/259] Remove a redundant mappend case.

---
 src/Split.hs | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index 029cff002..190aee1d5 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -125,7 +125,6 @@ instance Show a => Show (Line a) where
 
 instance Monoid (Line a) where
  mempty = EmptyLine
- mappend EmptyLine EmptyLine = EmptyLine
  mappend EmptyLine line = line
  mappend line EmptyLine = line
  mappend (Line c1 xs) (Line c2 ys) = Line (c1 || c2) (xs <> ys)

From e1b15b7bdc0ed785844393cb16935c72221116f8 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 13:29:04 -0500
Subject: [PATCH 059/259] Handle empty rows without reference to the Monoid
 instance for Row.

---
 src/Split.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 190aee1d5..8e1cd0747 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -139,12 +139,12 @@ diffToRows (Pure (Insert term)) (previousIndex, _) _ after = (rowWithInsertedLin
   where
     (afterLines, range) = termToLines term after
     rowWithInsertedLine (Line _ elements) = Row EmptyLine $ Line True [ Div (Just "insert") elements ]
-    rowWithInsertedLine EmptyLine = mempty
+    rowWithInsertedLine line = Row line line
 diffToRows (Pure (Delete term)) (_, previousIndex) before _ = (rowWithDeletedLine <$> lines, (range, Range previousIndex previousIndex))
   where
     (lines, range) = termToLines term before
     rowWithDeletedLine (Line _ elements) = Row (Line True [ Div (Just "delete") elements ]) EmptyLine
-    rowWithDeletedLine EmptyLine = mempty
+    rowWithDeletedLine line = Row line line
 diffToRows (Pure (Replace a b)) _ before after = (replacedRows, (leftRange, rightRange))
   where
     replacedRows = zipWithMaybe rowFromMaybeRows (replace <$> leftElements) (replace <$> rightElements)

From 3ef66954b6462ddd73aa7a36b034128b43c609a1 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 13:29:21 -0500
Subject: [PATCH 060/259] Remove the Monoid instance for `Row a`.

---
 src/Split.hs | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 8e1cd0747..84fe42610 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -129,10 +129,6 @@ instance Monoid (Line a) where
  mappend line EmptyLine = line
  mappend (Line c1 xs) (Line c2 ys) = Line (c1 || c2) (xs <> ys)
 
-instance Monoid (Row a) where
-  mempty = Row EmptyLine EmptyLine
-  mappend (Row x1 y1) (Row x2 y2) = Row (x1 <> x2) (y1 <> y2)
-
 diffToRows :: Diff a Info -> (Int, Int) -> String -> String -> ([Row HTML], (Range, Range))
 diffToRows (Free annotated) _ before after = annotatedToRows annotated before after
 diffToRows (Pure (Insert term)) (previousIndex, _) _ after = (rowWithInsertedLine <$> afterLines, (Range previousIndex previousIndex, range))

From 31afc5de115acb843225e09c8215b512e9beda88 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 13:36:08 -0500
Subject: [PATCH 061/259] Replace some $s with some .s.

---
 src/Split.hs | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 84fe42610..b37d6159c 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -152,7 +152,7 @@ diffToRows (Pure (Replace a b)) _ before after = (replacedRows, (leftRange, righ
 termToLines :: Term a Info -> String -> ([Line HTML], Range)
 termToLines (Info range categories :< syntax) source = (rows syntax, range)
   where
-    rows (Leaf _) = reverse $ foldl (adjoinLinesBy openElement) [] $ Line True . (:[]) <$> elements
+    rows (Leaf _) = reverse . foldl (adjoinLinesBy openElement) [] $ Line True . (:[]) <$> elements
     rows (Indexed i) = rewrapLineContentsIn (Ul $ classify categories) <$> childLines i
     rows (Fixed f) = rewrapLineContentsIn (Ul $ classify categories) <$> childLines f
     rows (Keyed k) = rewrapLineContentsIn (Dl $ classify categories) <$> childLines k
@@ -165,8 +165,7 @@ termToLines (Info range categories :< syntax) source = (rows syntax, range)
     sumLines (lines, previous) child = (allLines, end childRange)
       where
         separatorLines = contextLines (Range previous $ start childRange) source
-        unadjoinedLines = lines ++ separatorLines ++ childLines
-        allLines = reverse $ foldl (adjoinLinesBy openElement) [] unadjoinedLines
+        allLines = reverse . foldl (adjoinLinesBy openElement) [] $ lines ++ separatorLines ++ childLines
         (childLines, childRange) = termToLines child source
     elements = elementAndBreak (Span $ classify categories) =<< actualLines (substring range source)
 

From d500810f90ade95575aee7827f4cfc9ccfdfd9d5 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 14:20:13 -0500
Subject: [PATCH 062/259] Define a splitTermsByLines function over leaves.

---
 src/Split.hs | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/Split.hs b/src/Split.hs
index b37d6159c..1fc568950 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -148,6 +148,13 @@ diffToRows (Pure (Replace a b)) _ before after = (replacedRows, (leftRange, righ
     (leftElements, leftRange) = termToLines a before
     (rightElements, rightRange) = termToLines b after
 
+-- | Takes a term and a `source` and returns a list of lines and their range within `source`.
+splitTermByLines :: Term a Info -> String -> ([Line (Term a Info)], Range)
+splitTermByLines (Info range categories :< syntax) source = flip (,) range $ case syntax of
+  Leaf a -> reverse . foldl (adjoinLinesBy $ openTerm source) [] $
+    Line True . (:[]) . (:< Leaf a) . (`Info` categories) <$> scanl toRange (Range (start range) (start range)) (actualLines $ substring range source)
+  where toRange previous string = Range (end previous) $ end previous + length string
+
 -- | Takes a term and a `source` and returns a list of lines and their range within `source`.
 termToLines :: Term a Info -> String -> ([Line HTML], Range)
 termToLines (Info range categories :< syntax) source = (rows syntax, range)

From 6088777b69d471b2854fb80746bfe160b516ee4c Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 14:24:14 -0500
Subject: [PATCH 063/259] Add an actualLineRanges function.

---
 src/Split.hs | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/Split.hs b/src/Split.hs
index 1fc568950..653dc99ff 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -287,3 +287,8 @@ actualLines lines = case break (== '\n') lines of
   (l, lines') -> case lines' of
                       [] -> [ l ]
                       _:lines' -> (l ++ "\n") : actualLines lines'
+
+-- | Compute the line ranges within a given range of a string.
+actualLineRanges :: Range -> String -> [Range]
+actualLineRanges range = scanl toRange (Range (start range) (start range)) . actualLines . substring range
+  where toRange previous string = Range (end previous) $ end previous + length string

From aa0dd5d2caaab6e78c5b3daefc3bac3b6575c7a0 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 14:24:32 -0500
Subject: [PATCH 064/259] Define splitTermByLines over actualLineRanges.

---
 src/Split.hs | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 653dc99ff..9f258085b 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -152,8 +152,7 @@ diffToRows (Pure (Replace a b)) _ before after = (replacedRows, (leftRange, righ
 splitTermByLines :: Term a Info -> String -> ([Line (Term a Info)], Range)
 splitTermByLines (Info range categories :< syntax) source = flip (,) range $ case syntax of
   Leaf a -> reverse . foldl (adjoinLinesBy $ openTerm source) [] $
-    Line True . (:[]) . (:< Leaf a) . (`Info` categories) <$> scanl toRange (Range (start range) (start range)) (actualLines $ substring range source)
-  where toRange previous string = Range (end previous) $ end previous + length string
+    Line True . (:[]) . (:< Leaf a) . (`Info` categories) <$> actualLineRanges range source
 
 -- | Takes a term and a `source` and returns a list of lines and their range within `source`.
 termToLines :: Term a Info -> String -> ([Line HTML], Range)

From fb78fa7535389ccacbead019b0993b9132f344ec Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 14:30:20 -0500
Subject: [PATCH 065/259] Extract an `adjoin` binding in `termToLines`.

---
 src/Split.hs | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 9f258085b..cd1669448 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -158,20 +158,21 @@ splitTermByLines (Info range categories :< syntax) source = flip (,) range $ cas
 termToLines :: Term a Info -> String -> ([Line HTML], Range)
 termToLines (Info range categories :< syntax) source = (rows syntax, range)
   where
-    rows (Leaf _) = reverse . foldl (adjoinLinesBy openElement) [] $ Line True . (:[]) <$> elements
+    rows (Leaf _) = adjoin $ Line True . (:[]) <$> elements
     rows (Indexed i) = rewrapLineContentsIn (Ul $ classify categories) <$> childLines i
     rows (Fixed f) = rewrapLineContentsIn (Ul $ classify categories) <$> childLines f
     rows (Keyed k) = rewrapLineContentsIn (Dl $ classify categories) <$> childLines k
 
+    adjoin = reverse . foldl (adjoinLinesBy openElement) []
     rewrapLineContentsIn f (Line _ elements) = Line True [ f elements ]
     rewrapLineContentsIn _ EmptyLine = EmptyLine
     contextLines r s = Line True . (:[]) <$> textElements r s
     childLines i = let (lines, previous) = foldl sumLines ([], start range) i in
-      reverse . foldl (adjoinLinesBy openElement) [] $ lines ++ contextLines (Range previous (end range)) source
+      adjoin $ lines ++ contextLines (Range previous (end range)) source
     sumLines (lines, previous) child = (allLines, end childRange)
       where
         separatorLines = contextLines (Range previous $ start childRange) source
-        allLines = reverse . foldl (adjoinLinesBy openElement) [] $ lines ++ separatorLines ++ childLines
+        allLines = adjoin $ lines ++ separatorLines ++ childLines
         (childLines, childRange) = termToLines child source
     elements = elementAndBreak (Span $ classify categories) =<< actualLines (substring range source)
 

From 50d82831cd370864da237635fa75e0095bae9268 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 14:30:55 -0500
Subject: [PATCH 066/259] Inline the definition of separatorLines.

---
 src/Split.hs | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index cd1669448..9fb5fea34 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -171,8 +171,7 @@ termToLines (Info range categories :< syntax) source = (rows syntax, range)
       adjoin $ lines ++ contextLines (Range previous (end range)) source
     sumLines (lines, previous) child = (allLines, end childRange)
       where
-        separatorLines = contextLines (Range previous $ start childRange) source
-        allLines = adjoin $ lines ++ separatorLines ++ childLines
+        allLines = adjoin $ lines ++ contextLines (Range previous $ start childRange) source ++ childLines
         (childLines, childRange) = termToLines child source
     elements = elementAndBreak (Span $ classify categories) =<< actualLines (substring range source)
 

From dc2c130936664436a0b58936e3497401e07516e5 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 14:31:56 -0500
Subject: [PATCH 067/259] Tidy up the sumLines definition.

---
 src/Split.hs | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 9fb5fea34..f18dd7b8c 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -169,10 +169,8 @@ termToLines (Info range categories :< syntax) source = (rows syntax, range)
     contextLines r s = Line True . (:[]) <$> textElements r s
     childLines i = let (lines, previous) = foldl sumLines ([], start range) i in
       adjoin $ lines ++ contextLines (Range previous (end range)) source
-    sumLines (lines, previous) child = (allLines, end childRange)
-      where
-        allLines = adjoin $ lines ++ contextLines (Range previous $ start childRange) source ++ childLines
-        (childLines, childRange) = termToLines child source
+    sumLines (lines, previous) child = let (childLines, childRange) = termToLines child source in
+      (adjoin $ lines ++ contextLines (Range previous $ start childRange) source ++ childLines, end childRange)
     elements = elementAndBreak (Span $ classify categories) =<< actualLines (substring range source)
 
 -- | Given an Annotated and before/after strings, returns a list of `Row`s representing the newline-separated diff.

From ab79e9d99f9a767535f00b031ab09de5f4c9a51e Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 14:32:59 -0500
Subject: [PATCH 068/259] Extract the adjoining fold into an `adjoin` binding.

---
 src/Split.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index f18dd7b8c..1a5ef9daa 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -151,8 +151,8 @@ diffToRows (Pure (Replace a b)) _ before after = (replacedRows, (leftRange, righ
 -- | Takes a term and a `source` and returns a list of lines and their range within `source`.
 splitTermByLines :: Term a Info -> String -> ([Line (Term a Info)], Range)
 splitTermByLines (Info range categories :< syntax) source = flip (,) range $ case syntax of
-  Leaf a -> reverse . foldl (adjoinLinesBy $ openTerm source) [] $
-    Line True . (:[]) . (:< Leaf a) . (`Info` categories) <$> actualLineRanges range source
+  Leaf a -> adjoin $ Line True . (:[]) . (:< Leaf a) . (`Info` categories) <$> actualLineRanges range source
+  where adjoin = reverse . foldl (adjoinLinesBy $ openTerm source) []
 
 -- | Takes a term and a `source` and returns a list of lines and their range within `source`.
 termToLines :: Term a Info -> String -> ([Line HTML], Range)

From 8e652e80ee2722053d45a296193e10a309d75e41 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 14:56:55 -0500
Subject: [PATCH 069/259] Add a `contextLines` function.

---
 src/Split.hs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/Split.hs b/src/Split.hs
index 1a5ef9daa..d56414000 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -153,6 +153,7 @@ splitTermByLines :: Term a Info -> String -> ([Line (Term a Info)], Range)
 splitTermByLines (Info range categories :< syntax) source = flip (,) range $ case syntax of
   Leaf a -> adjoin $ Line True . (:[]) . (:< Leaf a) . (`Info` categories) <$> actualLineRanges range source
   where adjoin = reverse . foldl (adjoinLinesBy $ openTerm source) []
+        contextLines constructor range source = Line True . (:[]) . (:< constructor []) . (`Info` categories) <$> actualLineRanges range source
 
 -- | Takes a term and a `source` and returns a list of lines and their range within `source`.
 termToLines :: Term a Info -> String -> ([Line HTML], Range)

From 8fa370cb62b224e13b1bef4cec24a2992001ca7d Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 14:57:22 -0500
Subject: [PATCH 070/259] Add a childLines function.

This serves the same purpose as `sumLines` does in `termToLines`, but I
find the name preferable for this use case.
---
 src/Split.hs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/Split.hs b/src/Split.hs
index d56414000..4ff3627d0 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -154,6 +154,8 @@ splitTermByLines (Info range categories :< syntax) source = flip (,) range $ cas
   Leaf a -> adjoin $ Line True . (:[]) . (:< Leaf a) . (`Info` categories) <$> actualLineRanges range source
   where adjoin = reverse . foldl (adjoinLinesBy $ openTerm source) []
         contextLines constructor range source = Line True . (:[]) . (:< constructor []) . (`Info` categories) <$> actualLineRanges range source
+        childLines constructor (lines, previous) child = let (childLines, childRange) = splitTermByLines child source in
+          (adjoin $ lines ++ contextLines constructor (Range previous $ start childRange) source ++ childLines, end childRange)
 
 -- | Takes a term and a `source` and returns a list of lines and their range within `source`.
 termToLines :: Term a Info -> String -> ([Line HTML], Range)

From 426d83a60a9d6859859d982132e24c49b7379541 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 14:57:33 -0500
Subject: [PATCH 071/259] Define `splitTermByLines` over `Indexed` terms.

---
 src/Split.hs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/Split.hs b/src/Split.hs
index 4ff3627d0..452cde677 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -152,6 +152,8 @@ diffToRows (Pure (Replace a b)) _ before after = (replacedRows, (leftRange, righ
 splitTermByLines :: Term a Info -> String -> ([Line (Term a Info)], Range)
 splitTermByLines (Info range categories :< syntax) source = flip (,) range $ case syntax of
   Leaf a -> adjoin $ Line True . (:[]) . (:< Leaf a) . (`Info` categories) <$> actualLineRanges range source
+  Indexed children -> let (lines, previous) = foldl (childLines Indexed) ([], start range) children in
+    adjoin $ lines ++ contextLines Indexed (Range previous $ end range) source
   where adjoin = reverse . foldl (adjoinLinesBy $ openTerm source) []
         contextLines constructor range source = Line True . (:[]) . (:< constructor []) . (`Info` categories) <$> actualLineRanges range source
         childLines constructor (lines, previous) child = let (childLines, childRange) = splitTermByLines child source in

From cf6f96dcd2ae91727cc43b53086027f5e4a8fb50 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 14:59:43 -0500
Subject: [PATCH 072/259] Extract a function to adjoin the lines in child
 terms.

---
 src/Split.hs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/Split.hs b/src/Split.hs
index 452cde677..ac8a873ec 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -155,6 +155,8 @@ splitTermByLines (Info range categories :< syntax) source = flip (,) range $ cas
   Indexed children -> let (lines, previous) = foldl (childLines Indexed) ([], start range) children in
     adjoin $ lines ++ contextLines Indexed (Range previous $ end range) source
   where adjoin = reverse . foldl (adjoinLinesBy $ openTerm source) []
+        adjoinTermLines constructor children = let (lines, previous) = foldl (childLines constructor) ([], start range) children in
+          adjoin $ lines ++ contextLines constructor (Range previous $ end range) source
         contextLines constructor range source = Line True . (:[]) . (:< constructor []) . (`Info` categories) <$> actualLineRanges range source
         childLines constructor (lines, previous) child = let (childLines, childRange) = splitTermByLines child source in
           (adjoin $ lines ++ contextLines constructor (Range previous $ start childRange) source ++ childLines, end childRange)

From 29c136c80f13f52fe599d0d3da821469d4c3fa78 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 15:00:03 -0500
Subject: [PATCH 073/259] Define `splitTermByLines` over `Indexed` terms using
 `adjoinTermLines`.

---
 src/Split.hs | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index ac8a873ec..17b2d7ccc 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -152,8 +152,7 @@ diffToRows (Pure (Replace a b)) _ before after = (replacedRows, (leftRange, righ
 splitTermByLines :: Term a Info -> String -> ([Line (Term a Info)], Range)
 splitTermByLines (Info range categories :< syntax) source = flip (,) range $ case syntax of
   Leaf a -> adjoin $ Line True . (:[]) . (:< Leaf a) . (`Info` categories) <$> actualLineRanges range source
-  Indexed children -> let (lines, previous) = foldl (childLines Indexed) ([], start range) children in
-    adjoin $ lines ++ contextLines Indexed (Range previous $ end range) source
+  Indexed children -> adjoinTermLines Indexed children
   where adjoin = reverse . foldl (adjoinLinesBy $ openTerm source) []
         adjoinTermLines constructor children = let (lines, previous) = foldl (childLines constructor) ([], start range) children in
           adjoin $ lines ++ contextLines constructor (Range previous $ end range) source

From 4030b8d9e2bf66223d45666c06c3c5a3c0b17fae Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 15:00:40 -0500
Subject: [PATCH 074/259] Define splitTermByLines over Fixed terms.

---
 src/Split.hs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/Split.hs b/src/Split.hs
index 17b2d7ccc..c0fb59759 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -153,6 +153,7 @@ splitTermByLines :: Term a Info -> String -> ([Line (Term a Info)], Range)
 splitTermByLines (Info range categories :< syntax) source = flip (,) range $ case syntax of
   Leaf a -> adjoin $ Line True . (:[]) . (:< Leaf a) . (`Info` categories) <$> actualLineRanges range source
   Indexed children -> adjoinTermLines Indexed children
+  Fixed children -> adjoinTermLines Fixed children
   where adjoin = reverse . foldl (adjoinLinesBy $ openTerm source) []
         adjoinTermLines constructor children = let (lines, previous) = foldl (childLines constructor) ([], start range) children in
           adjoin $ lines ++ contextLines constructor (Range previous $ end range) source

From 4a15e11f3b2c9b88b99d71aa0d94d0e15f7efdac Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 15:09:39 -0500
Subject: [PATCH 075/259] OrderedMaps of Eq keys are Monoids.

---
 src/OrderedMap.hs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/OrderedMap.hs b/src/OrderedMap.hs
index bb62738b9..04fa13c5f 100644
--- a/src/OrderedMap.hs
+++ b/src/OrderedMap.hs
@@ -16,6 +16,10 @@ module OrderedMap (
 data OrderedMap key value = OrderedMap { toList :: [(key, value)] }
   deriving (Show, Eq, Functor, Foldable, Traversable)
 
+instance Eq key => Monoid (OrderedMap key value) where
+  mempty = fromList []
+  mappend = union
+
 fromList :: [(key, value)] -> OrderedMap key value
 fromList list = OrderedMap list
 

From fcfe258014d4360fb284d2f3b305584398a0ec16 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 15:11:59 -0500
Subject: [PATCH 076/259] Implement `!` using `fromMaybe`.

---
 src/OrderedMap.hs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/OrderedMap.hs b/src/OrderedMap.hs
index 04fa13c5f..116b4d61c 100644
--- a/src/OrderedMap.hs
+++ b/src/OrderedMap.hs
@@ -13,6 +13,8 @@ module OrderedMap (
   , difference
   ) where
 
+import qualified Data.Maybe as Maybe
+
 data OrderedMap key value = OrderedMap { toList :: [(key, value)] }
   deriving (Show, Eq, Functor, Foldable, Traversable)
 
@@ -29,9 +31,7 @@ keys (OrderedMap pairs) = fst <$> pairs
 infixl 9 !
 
 (!) :: Eq key => OrderedMap key value -> key -> value
-map ! key = case OrderedMap.lookup key map of
-  Just value -> value
-  Nothing -> error "no value found for key"
+map ! key = Maybe.fromMaybe (error "no value found for key") $ OrderedMap.lookup key map
 
 lookup :: Eq key => key -> OrderedMap key value -> Maybe value
 lookup key = Prelude.lookup key . toList

From bba1dd7f4baac69bb551c88e820b5c560b50cadb Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 15:12:05 -0500
Subject: [PATCH 077/259] Eta reduce fromList.

---
 src/OrderedMap.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/OrderedMap.hs b/src/OrderedMap.hs
index 116b4d61c..198b014dd 100644
--- a/src/OrderedMap.hs
+++ b/src/OrderedMap.hs
@@ -23,7 +23,7 @@ instance Eq key => Monoid (OrderedMap key value) where
   mappend = union
 
 fromList :: [(key, value)] -> OrderedMap key value
-fromList list = OrderedMap list
+fromList = OrderedMap
 
 keys :: OrderedMap key value -> [key]
 keys (OrderedMap pairs) = fst <$> pairs

From d2e4646b5b7eef3170e490e10e0d45825d1beb21 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 15:12:26 -0500
Subject: [PATCH 078/259] Drop redundant parentheses.

---
 src/OrderedMap.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/OrderedMap.hs b/src/OrderedMap.hs
index 198b014dd..9076e5b5e 100644
--- a/src/OrderedMap.hs
+++ b/src/OrderedMap.hs
@@ -50,7 +50,7 @@ unions :: Eq key => [OrderedMap key value] -> OrderedMap key value
 unions = foldl union empty
 
 intersectionWith :: Eq key => (a -> b -> c) -> OrderedMap key a -> OrderedMap key b -> OrderedMap key c
-intersectionWith combine (OrderedMap a) (OrderedMap b) = OrderedMap $ a >>= (\ (key, value) -> maybe [] (pure . ((,) key) . combine value) $ Prelude.lookup key b)
+intersectionWith combine (OrderedMap a) (OrderedMap b) = OrderedMap $ a >>= (\ (key, value) -> maybe [] (pure . (,) key . combine value) $ Prelude.lookup key b)
 
 difference :: Eq key => OrderedMap key a -> OrderedMap key b -> OrderedMap key a
 difference (OrderedMap a) (OrderedMap b) = OrderedMap $ filter (not . (`elem` extant) . fst) a

From 66e6c0d69b4fb9125742c3da0c44df4b3b7d68a4 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 15:13:37 -0500
Subject: [PATCH 079/259] Define `contextLines` over `Monoid`s using `mempty`.

---
 src/Split.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index c0fb59759..76bf7d61f 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -157,7 +157,7 @@ splitTermByLines (Info range categories :< syntax) source = flip (,) range $ cas
   where adjoin = reverse . foldl (adjoinLinesBy $ openTerm source) []
         adjoinTermLines constructor children = let (lines, previous) = foldl (childLines constructor) ([], start range) children in
           adjoin $ lines ++ contextLines constructor (Range previous $ end range) source
-        contextLines constructor range source = Line True . (:[]) . (:< constructor []) . (`Info` categories) <$> actualLineRanges range source
+        contextLines constructor range source = Line True . (:[]) . (:< constructor mempty) . (`Info` categories) <$> actualLineRanges range source
         childLines constructor (lines, previous) child = let (childLines, childRange) = splitTermByLines child source in
           (adjoin $ lines ++ contextLines constructor (Range previous $ start childRange) source ++ childLines, end childRange)
 

From bd680b966dd7b81f5b022e3f325f5b56ec96de79 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 15:13:57 -0500
Subject: [PATCH 080/259] Define splitTermByLines over Keyed terms.

---
 src/Split.hs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/Split.hs b/src/Split.hs
index 76bf7d61f..f636a2f07 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -154,6 +154,7 @@ splitTermByLines (Info range categories :< syntax) source = flip (,) range $ cas
   Leaf a -> adjoin $ Line True . (:[]) . (:< Leaf a) . (`Info` categories) <$> actualLineRanges range source
   Indexed children -> adjoinTermLines Indexed children
   Fixed children -> adjoinTermLines Fixed children
+  Keyed children -> adjoinTermLines Keyed children
   where adjoin = reverse . foldl (adjoinLinesBy $ openTerm source) []
         adjoinTermLines constructor children = let (lines, previous) = foldl (childLines constructor) ([], start range) children in
           adjoin $ lines ++ contextLines constructor (Range previous $ end range) source

From 5bd9684a1dd9b5b5a142722d7fd9c186e748f953 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 15:14:26 -0500
Subject: [PATCH 081/259] Remove weird backticks.

---
 src/Split.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index f636a2f07..d6296db89 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -148,7 +148,7 @@ diffToRows (Pure (Replace a b)) _ before after = (replacedRows, (leftRange, righ
     (leftElements, leftRange) = termToLines a before
     (rightElements, rightRange) = termToLines b after
 
--- | Takes a term and a `source` and returns a list of lines and their range within `source`.
+-- | Takes a term and a source and returns a list of lines and their range within source.
 splitTermByLines :: Term a Info -> String -> ([Line (Term a Info)], Range)
 splitTermByLines (Info range categories :< syntax) source = flip (,) range $ case syntax of
   Leaf a -> adjoin $ Line True . (:[]) . (:< Leaf a) . (`Info` categories) <$> actualLineRanges range source
@@ -162,7 +162,7 @@ splitTermByLines (Info range categories :< syntax) source = flip (,) range $ cas
         childLines constructor (lines, previous) child = let (childLines, childRange) = splitTermByLines child source in
           (adjoin $ lines ++ contextLines constructor (Range previous $ start childRange) source ++ childLines, end childRange)
 
--- | Takes a term and a `source` and returns a list of lines and their range within `source`.
+-- | Takes a term and a source and returns a list of lines and their range within source.
 termToLines :: Term a Info -> String -> ([Line HTML], Range)
 termToLines (Info range categories :< syntax) source = (rows syntax, range)
   where

From 955874560e4f298c901b68e03409c174f66c42a9 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 18:55:54 -0500
Subject: [PATCH 082/259] Move the ranges from annotatedToRows into diffToRows.

---
 src/Split.hs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index d6296db89..d2c31eea5 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -130,7 +130,7 @@ instance Monoid (Line a) where
  mappend (Line c1 xs) (Line c2 ys) = Line (c1 || c2) (xs <> ys)
 
 diffToRows :: Diff a Info -> (Int, Int) -> String -> String -> ([Row HTML], (Range, Range))
-diffToRows (Free annotated) _ before after = annotatedToRows annotated before after
+diffToRows (Free annotated@(Annotated (Info left _, Info right _) _)) _ before after = (annotatedToRows annotated before after, (left, right))
 diffToRows (Pure (Insert term)) (previousIndex, _) _ after = (rowWithInsertedLine <$> afterLines, (Range previousIndex previousIndex, range))
   where
     (afterLines, range) = termToLines term after
@@ -182,8 +182,8 @@ termToLines (Info range categories :< syntax) source = (rows syntax, range)
     elements = elementAndBreak (Span $ classify categories) =<< actualLines (substring range source)
 
 -- | Given an Annotated and before/after strings, returns a list of `Row`s representing the newline-separated diff.
-annotatedToRows :: Annotated a (Info, Info) (Diff a Info) -> String -> String -> ([Row HTML], (Range, Range))
-annotatedToRows (Annotated (Info left leftCategories, Info right rightCategories) syntax) before after = (rows syntax, ranges)
+annotatedToRows :: Annotated a (Info, Info) (Diff a Info) -> String -> String -> [Row HTML]
+annotatedToRows (Annotated (Info left leftCategories, Info right rightCategories) syntax) before after = rows syntax
   where
     rows (Leaf _) = zipWithMaybe rowFromMaybeRows leftElements rightElements
     rows (Indexed i) = rewrapRowContentsIn Ul <$> childRows i

From 07a90b7d09d616de0a6c32fd15c923111895ca81 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 19:20:53 -0500
Subject: [PATCH 083/259] Apply the constructor to mempty outside of
 contextLines.

---
 src/Split.hs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index d2c31eea5..5c0db9b1b 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -156,9 +156,9 @@ splitTermByLines (Info range categories :< syntax) source = flip (,) range $ cas
   Fixed children -> adjoinTermLines Fixed children
   Keyed children -> adjoinTermLines Keyed children
   where adjoin = reverse . foldl (adjoinLinesBy $ openTerm source) []
-        adjoinTermLines constructor children = let (lines, previous) = foldl (childLines constructor) ([], start range) children in
-          adjoin $ lines ++ contextLines constructor (Range previous $ end range) source
-        contextLines constructor range source = Line True . (:[]) . (:< constructor mempty) . (`Info` categories) <$> actualLineRanges range source
+        adjoinTermLines constructor children = let (lines, previous) = foldl (childLines $ constructor mempty) ([], start range) children in
+          adjoin $ lines ++ contextLines (constructor mempty) (Range previous $ end range) source
+        contextLines constructor range source = Line True . (:[]) . (:< constructor) . (`Info` categories) <$> actualLineRanges range source
         childLines constructor (lines, previous) child = let (childLines, childRange) = splitTermByLines child source in
           (adjoin $ lines ++ contextLines constructor (Range previous $ start childRange) source ++ childLines, end childRange)
 

From 6a80813d191181b3800b5acc5149cb9bd2e035f1 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 19:21:29 -0500
Subject: [PATCH 084/259] Use contextLines to define splitTermByLines over
 leaves.

---
 src/Split.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index 5c0db9b1b..1b558e360 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -151,7 +151,7 @@ diffToRows (Pure (Replace a b)) _ before after = (replacedRows, (leftRange, righ
 -- | Takes a term and a source and returns a list of lines and their range within source.
 splitTermByLines :: Term a Info -> String -> ([Line (Term a Info)], Range)
 splitTermByLines (Info range categories :< syntax) source = flip (,) range $ case syntax of
-  Leaf a -> adjoin $ Line True . (:[]) . (:< Leaf a) . (`Info` categories) <$> actualLineRanges range source
+  Leaf a -> adjoin $ contextLines (Leaf a) range source
   Indexed children -> adjoinTermLines Indexed children
   Fixed children -> adjoinTermLines Fixed children
   Keyed children -> adjoinTermLines Keyed children

From 65cb2837cba9101bddd53f8fb27fe4a3064b5bf4 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 19:38:11 -0500
Subject: [PATCH 085/259] Add a zipWithDefaults function.

---
 src/Split.hs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/Split.hs b/src/Split.hs
index 1b558e360..e0bd34765 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -283,6 +283,9 @@ zipWithMaybe f la lb = take len $ zipWith f la' lb'
     la' = (Just <$> la) ++ repeat Nothing
     lb' = (Just <$> lb) ++ repeat Nothing
 
+zipWithDefaults :: (a -> b -> c) -> a -> b -> [a] -> [b] -> [c]
+zipWithDefaults f da db a b = take (max (length a) (length b)) $ zipWith f (a ++ repeat da) (b ++ repeat db)
+
 classify :: Set.Set Category -> Maybe ClassName
 classify categories = ("category-" ++) <$> maybeLast categories
 

From 4486cb90a3f169b41f7ea65d0c4ee4664141a4ef Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 19:38:57 -0500
Subject: [PATCH 086/259] Define zipWithMaybe in terms of zipWithDefaults.

---
 src/Split.hs | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index e0bd34765..fb4edbe5e 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -277,11 +277,7 @@ adjoinLinesBy f (prev:rest) line | Just _ <- openLineBy f [ prev ] = (prev <> li
 adjoinLinesBy _ lines line = line : lines
 
 zipWithMaybe :: (Maybe a -> Maybe b -> c) -> [a] -> [b] -> [c]
-zipWithMaybe f la lb = take len $ zipWith f la' lb'
-  where
-    len = max (length la) (length lb)
-    la' = (Just <$> la) ++ repeat Nothing
-    lb' = (Just <$> lb) ++ repeat Nothing
+zipWithMaybe f a b = zipWithDefaults f Nothing Nothing (Just <$> a) (Just <$> b)
 
 zipWithDefaults :: (a -> b -> c) -> a -> b -> [a] -> [b] -> [c]
 zipWithDefaults f da db a b = take (max (length a) (length b)) $ zipWith f (a ++ repeat da) (b ++ repeat db)

From 8cdb0a582a3a1b431739a02ae72e15b4caa24603 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 19:40:00 -0500
Subject: [PATCH 087/259] Add a splitAnnotatedByLines function defined over
 leaves.

---
 src/Split.hs | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/Split.hs b/src/Split.hs
index fb4edbe5e..6b92c1b0a 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -181,6 +181,11 @@ termToLines (Info range categories :< syntax) source = (rows syntax, range)
       (adjoin $ lines ++ contextLines (Range previous $ start childRange) source ++ childLines, end childRange)
     elements = elementAndBreak (Span $ classify categories) =<< actualLines (substring range source)
 
+splitAnnotatedByLines :: (String, String) -> (Range, Range) -> (Set.Set Category, Set.Set Category) -> Syntax a (Diff a Info) -> [Row (Term a Info)]
+splitAnnotatedByLines sources ranges categories syntax = case syntax of
+  Leaf a -> zipWithDefaults Row EmptyLine EmptyLine (contextLines (Leaf a) (fst ranges) (fst categories) (fst sources)) (contextLines (Leaf a) (snd ranges) (snd categories) (snd sources))
+  where contextLines constructor range categories source = Line False . (:[]) . (:< constructor) . (`Info` categories) <$> actualLineRanges range source
+
 -- | Given an Annotated and before/after strings, returns a list of `Row`s representing the newline-separated diff.
 annotatedToRows :: Annotated a (Info, Info) (Diff a Info) -> String -> String -> [Row HTML]
 annotatedToRows (Annotated (Info left leftCategories, Info right rightCategories) syntax) before after = rows syntax

From 61067a6f2ae2560c132610d3be5f07993ce26c68 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 19:44:07 -0500
Subject: [PATCH 088/259] Remove the ranges from the annotatedToRows tests.

---
 test/SplitSpec.hs | 26 +++++++++++++-------------
 1 file changed, 13 insertions(+), 13 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index f462dec0a..7d0f238df 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -32,48 +32,48 @@ spec :: Spec
 spec = do
   describe "annotatedToRows" $ do
     it "outputs one row for single-line unchanged leaves" $
-      annotatedToRows (unchanged "a" "leaf" (Leaf "")) "a" "a" `shouldBe` ([ Row (Line False [ span "a" ]) (Line False [ span "a" ]) ], (Range 0 1, Range 0 1))
+      annotatedToRows (unchanged "a" "leaf" (Leaf "")) "a" "a" `shouldBe` [ Row (Line False [ span "a" ]) (Line False [ span "a" ]) ]
 
     it "outputs one row for single-line empty unchanged indexed nodes" $
-      annotatedToRows (unchanged "[]" "branch" (Indexed [])) "[]" "[]" `shouldBe` ([ Row (Line False [ Ul (Just "category-branch") [ Text "[]" ] ]) (Line False [ Ul (Just "category-branch") [ Text "[]" ] ]) ], (Range 0 2, Range 0 2))
+      annotatedToRows (unchanged "[]" "branch" (Indexed [])) "[]" "[]" `shouldBe` [ Row (Line False [ Ul (Just "category-branch") [ Text "[]" ] ]) (Line False [ Ul (Just "category-branch") [ Text "[]" ] ]) ]
 
     it "outputs one row for single-line non-empty unchanged indexed nodes" $
       annotatedToRows (unchanged "[ a, b ]" "branch" (Indexed [
         Free . offsetAnnotated 2 2 $ unchanged "a" "leaf" (Leaf ""),
         Free . offsetAnnotated 5 5 $ unchanged "b" "leaf" (Leaf "")
-      ])) "[ a, b ]" "[ a, b ]" `shouldBe` ([ Row (Line False [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ", ", span "b", Text " ]" ] ]) (Line False [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ", ", span "b", Text " ]" ] ]) ], (Range 0 8, Range 0 8))
+      ])) "[ a, b ]" "[ a, b ]" `shouldBe` [ Row (Line False [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ", ", span "b", Text " ]" ] ]) (Line False [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ", ", span "b", Text " ]" ] ]) ]
 
     it "outputs one row for single-line non-empty formatted indexed nodes" $
       annotatedToRows (formatted "[ a, b ]" "[ a,  b ]" "branch" (Indexed [
         Free . offsetAnnotated 2 2 $ unchanged "a" "leaf" (Leaf ""),
         Free . offsetAnnotated 5 6 $ unchanged "b" "leaf" (Leaf "")
-      ])) "[ a, b ]" "[ a,  b ]" `shouldBe` ([ Row (Line False [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ", ", span "b", Text " ]" ] ]) (Line False [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ",  ", span "b", Text " ]" ] ]) ], (Range 0 8, Range 0 9))
+      ])) "[ a, b ]" "[ a,  b ]" `shouldBe` [ Row (Line False [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ", ", span "b", Text " ]" ] ]) (Line False [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ",  ", span "b", Text " ]" ] ]) ]
 
     it "outputs two rows for two-line non-empty unchanged indexed nodes" $
       annotatedToRows (unchanged "[ a,\nb ]" "branch" (Indexed [
         Free . offsetAnnotated 2 2 $ unchanged "a" "leaf" (Leaf ""),
         Free . offsetAnnotated 5 5 $ unchanged "b" "leaf" (Leaf "")
       ])) "[ a,\nb ]" "[ a,\nb ]" `shouldBe`
-      ([
+      [
           Row (Line False [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ",", Break ] ])
               (Line False [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ",", Break] ]),
           Row (Line False [ Ul (Just "category-branch") [ span "b", Text " ]" ] ])
               (Line False [ Ul (Just "category-branch") [ span "b", Text " ]" ] ])
-       ], (Range 0 8, Range 0 8))
+      ]
 
     it "outputs two rows for two-line non-empty formatted indexed nodes" $
       annotatedToRows (formatted "[ a,\nb ]" "[\na,\nb ]" "branch" (Indexed [
         Free . offsetAnnotated 2 2 $ unchanged "a" "leaf" (Leaf ""),
         Free . offsetAnnotated 5 5 $ unchanged "b" "leaf" (Leaf "")
       ])) "[ a,\nb ]" "[\na,\nb ]" `shouldBe`
-      ([
+      [
           Row (Line False [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ",", Break ] ])
               (Line False [ Ul (Just "category-branch") [ Text "[", Break ] ]),
           Row EmptyLine
               (Line False [ Ul (Just "category-branch") [ span "a", Text ",", Break ] ]),
           Row (Line False [ Ul (Just "category-branch") [ span "b", Text " ]" ] ])
               (Line False [ Ul (Just "category-branch") [ span "b", Text " ]" ] ])
-       ], (Range 0 8, Range 0 8))
+      ]
 
     it "" $
       let (sourceA, sourceB) = ("[\na\n,\nb]", "[a,b]") in
@@ -81,7 +81,7 @@ spec = do
           Free . offsetAnnotated 2 1 $ unchanged "a" "leaf" (Leaf ""),
           Free . offsetAnnotated 6 3 $ unchanged "b" "leaf" (Leaf "")
         ])) sourceA sourceB `shouldBe`
-        ([
+        [
             Row (Line False [ Ul (Just "category-branch") [ Text "[", Break ] ])
                 (Line False [ Ul (Just "category-branch") [ Text "[", span "a", Text ",", span "b", Text "]" ] ]),
             Row (Line False [ Ul (Just "category-branch") [ span "a", Break ] ])
@@ -90,7 +90,7 @@ spec = do
                 EmptyLine,
             Row (Line False [ Ul (Just "category-branch") [ span "b", Text "]" ] ])
                 EmptyLine
-        ], (Range 0 8, Range 0 5))
+        ]
 
     it "should split multi-line deletions across multiple rows" $
       let (sourceA, sourceB) = ("/*\n*/\na", "a") in
@@ -98,11 +98,11 @@ spec = do
           Pure . Delete $ (Info (Range 0 5) (Set.fromList ["leaf"]) :< Leaf ""),
           Free . offsetAnnotated 6 0 $ unchanged "a" "leaf" (Leaf "")
         ])) sourceA sourceB `shouldBe`
-        ([
+        [
           Row (Line True [ Ul (Just "category-branch") [ Div (Just "delete") [ span "/*", Break ] ] ]) EmptyLine,
           Row (Line True [ Ul (Just "category-branch") [ Div (Just "delete") [ span "*/" ], Break ] ]) EmptyLine,
           Row (Line False [ Ul (Just "category-branch") [ span "a" ] ]) (Line False [ Ul (Just "category-branch") [ span "a" ] ])
-        ], (Range 0 7, Range 0 1))
+        ]
 
     describe "unicode" $
       it "equivalent precomposed and decomposed characters are not equal" $
@@ -110,7 +110,7 @@ spec = do
             syntax = Leaf . Pure $ Replace (info sourceA "leaf" :< Leaf "") (info sourceB "leaf" :< Leaf "")
         in
             annotatedToRows (formatted sourceA sourceB "leaf" syntax) sourceA sourceB `shouldBe`
-            ([ Row (Line False [ span "t\776" ]) (Line False [ span "\7831"]) ], (Range 0 2, Range 0 1))
+            [ Row (Line False [ span "t\776" ]) (Line False [ span "\7831"]) ]
 
 
   describe "adjoinRowsBy" $ do

From b45e10eb92e740923493279800ac6b52a3a799bf Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 19:54:40 -0500
Subject: [PATCH 089/259] Port the termToLines test to splitTermByLines.

---
 test/SplitSpec.hs | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 7d0f238df..97252f4d1 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -143,6 +143,15 @@ spec = do
         Line True [ span "*/" ]
       ], Range 0 5)
 
+  describe "splitTermByLines" $ do
+    it "splits multi-line terms into multiple lines" $
+      let categories = Set.singleton "leaf" in splitTermByLines (Info (Range 0 5) categories :< Leaf "") "/*\n*/"
+      `shouldBe`
+      ([
+        Line True [ Info (Range 0 3) categories :< Leaf "" ],
+        Line True [ Info (Range 3 5) categories :< Leaf "" ]
+      ], Range 0 5)
+
   describe "openLineBy" $ do
     it "should produce the earliest non-empty line in a list, if open" $
       openLineBy openElement [

From 60edd3b19a59444de832d22d10c0950bc08dfc0a Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 20:02:17 -0500
Subject: [PATCH 090/259] Omit the categories in the splitTermByLines test.

---
 test/SplitSpec.hs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 97252f4d1..6448a15dc 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -145,11 +145,11 @@ spec = do
 
   describe "splitTermByLines" $ do
     it "splits multi-line terms into multiple lines" $
-      let categories = Set.singleton "leaf" in splitTermByLines (Info (Range 0 5) categories :< Leaf "") "/*\n*/"
+      splitTermByLines (Info (Range 0 5) mempty :< Leaf "") "/*\n*/"
       `shouldBe`
       ([
-        Line True [ Info (Range 0 3) categories :< Leaf "" ],
-        Line True [ Info (Range 3 5) categories :< Leaf "" ]
+        Line True [ Info (Range 0 3) mempty :< Leaf "" ],
+        Line True [ Info (Range 3 5) mempty :< Leaf "" ]
       ], Range 0 5)
 
   describe "openLineBy" $ do

From d1abf65cdd7f670e70df18141ec05ecbb8772038 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 20:04:05 -0500
Subject: [PATCH 091/259] Test openLineBy over openTerm.

---
 test/SplitSpec.hs | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 6448a15dc..2eebb92e9 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -160,11 +160,22 @@ spec = do
         Line True [ Div (Just "delete") [ span "/*", Break ] ]
       ] `shouldBe` (Just $ Line True [ Div (Just "delete") [ span "*/" ] ])
 
+    it "should produce the earliest non-empty line in a list, if open" $
+      openLineBy (openTerm "\n ") [
+        Line True [ Info (Range 1 2) mempty :< Leaf "" ],
+        Line True [ Info (Range 0 1) mempty :< Leaf "" ]
+      ] `shouldBe` (Just $ Line True [ Info (Range 1 2) mempty :< Leaf "" ])
+
     it "should return Nothing if the earliest non-empty line is closed" $
       openLineBy openElement [
         Line True [ Div (Just "delete") [ span " * Debugging", Break ] ]
       ] `shouldBe` Nothing
 
+    it "should return Nothing if the earliest non-empty line is closed" $
+      openLineBy (openTerm "\n") [
+        Line True [ Info (Range 0 1) mempty :< Leaf "" ]
+      ] `shouldBe` Nothing
+
     where
       rightRowText text = rightRow [ Text text ]
       rightRow xs = Row EmptyLine (Line False xs)

From 7ee39b2d404479f7cfe794fb30a70d8d44cb423b Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 20:06:19 -0500
Subject: [PATCH 092/259] Test that openTerm classifies strings ending with
 newlines as closed.

---
 test/SplitSpec.hs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 2eebb92e9..66c56efe4 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -176,6 +176,10 @@ spec = do
         Line True [ Info (Range 0 1) mempty :< Leaf "" ]
       ] `shouldBe` Nothing
 
+  describe "openTerm" $ do
+    it "should return Nothing for terms whose substring ends with a newline" $
+      openTerm " \n" (Info (Range 0 2) mempty :< Leaf "") `shouldBe` Nothing
+
     where
       rightRowText text = rightRow [ Text text ]
       rightRow xs = Row EmptyLine (Line False xs)

From 41e03beb85e4f978f4cd32379c71d72879bc91ef Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 20:07:53 -0500
Subject: [PATCH 093/259] =?UTF-8?q?Tweak=20the=20test=20name=E2=80=99s=20w?=
 =?UTF-8?q?ording.?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 test/SplitSpec.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 66c56efe4..a11b9bbbc 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -177,7 +177,7 @@ spec = do
       ] `shouldBe` Nothing
 
   describe "openTerm" $ do
-    it "should return Nothing for terms whose substring ends with a newline" $
+    it "returns Nothing for terms whose substring ends with a newline" $
       openTerm " \n" (Info (Range 0 2) mempty :< Leaf "") `shouldBe` Nothing
 
     where

From 1f6440e7a1f744c42fa3cef58e37b01e74407483 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 20:08:05 -0500
Subject: [PATCH 094/259] Test that openTerm returns Just for open terms.

---
 test/SplitSpec.hs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index a11b9bbbc..241c2706c 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -177,6 +177,9 @@ spec = do
       ] `shouldBe` Nothing
 
   describe "openTerm" $ do
+    it "returns Just the term if its substring does not end with a newline" $
+      let term = Info (Range 0 2) mempty :< Leaf "" in openTerm "  " term `shouldBe` Just term
+
     it "returns Nothing for terms whose substring ends with a newline" $
       openTerm " \n" (Info (Range 0 2) mempty :< Leaf "") `shouldBe` Nothing
 

From d99be907d6930c37471dfec903975584666804ab Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 20:08:47 -0500
Subject: [PATCH 095/259] Fix the inverted sense of openTerm.

---
 src/Split.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 6b92c1b0a..56e3b4e89 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -267,8 +267,8 @@ openElement h = Just h
 
 openTerm :: String -> Term a Info -> Maybe (Term a Info)
 openTerm source term@(Info range _ :< _) = case (source !!) <$> maybeLastIndex range of
-  Just '\n' -> Just term
-  _ -> Nothing
+  Just '\n' -> Nothing
+  _ -> Just term
 
 openLineBy :: (a -> Maybe a) -> [Line a] -> Maybe (Line a)
 openLineBy _ [] = Nothing

From a69366cf4b7da2f019d144abc347756a2fbfec66 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 20:21:55 -0500
Subject: [PATCH 096/259] Always drop the initial range.

---
 src/Split.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index 56e3b4e89..c5999b1fe 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -299,5 +299,5 @@ actualLines lines = case break (== '\n') lines of
 
 -- | Compute the line ranges within a given range of a string.
 actualLineRanges :: Range -> String -> [Range]
-actualLineRanges range = scanl toRange (Range (start range) (start range)) . actualLines . substring range
+actualLineRanges range = drop 1 . scanl toRange (Range (start range) (start range)) . actualLines . substring range
   where toRange previous string = Range (end previous) $ end previous + length string

From 2c3ff54dc6a1916b819ea748b2c5a703a9c2d125 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 20:23:56 -0500
Subject: [PATCH 097/259] Assertive assertions.

---
 test/SplitSpec.hs | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 241c2706c..8de15986b 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -92,7 +92,7 @@ spec = do
                 EmptyLine
         ]
 
-    it "should split multi-line deletions across multiple rows" $
+    it "splits multi-line deletions across multiple rows" $
       let (sourceA, sourceB) = ("/*\n*/\na", "a") in
         annotatedToRows (formatted sourceA sourceB "branch" (Indexed [
           Pure . Delete $ (Info (Range 0 5) (Set.fromList ["leaf"]) :< Leaf ""),
@@ -153,25 +153,25 @@ spec = do
       ], Range 0 5)
 
   describe "openLineBy" $ do
-    it "should produce the earliest non-empty line in a list, if open" $
+    it "produces the earliest non-empty line in a list, if open" $
       openLineBy openElement [
         Line True [ Div (Just "delete") [ span "*/" ] ],
         Line True [ Div (Just "delete") [ span " * Debugging", Break ] ],
         Line True [ Div (Just "delete") [ span "/*", Break ] ]
       ] `shouldBe` (Just $ Line True [ Div (Just "delete") [ span "*/" ] ])
 
-    it "should produce the earliest non-empty line in a list, if open" $
+    it "produces the earliest non-empty line in a list, if open" $
       openLineBy (openTerm "\n ") [
         Line True [ Info (Range 1 2) mempty :< Leaf "" ],
         Line True [ Info (Range 0 1) mempty :< Leaf "" ]
       ] `shouldBe` (Just $ Line True [ Info (Range 1 2) mempty :< Leaf "" ])
 
-    it "should return Nothing if the earliest non-empty line is closed" $
+    it "returns Nothing if the earliest non-empty line is closed" $
       openLineBy openElement [
         Line True [ Div (Just "delete") [ span " * Debugging", Break ] ]
       ] `shouldBe` Nothing
 
-    it "should return Nothing if the earliest non-empty line is closed" $
+    it "returns Nothing if the earliest non-empty line is closed" $
       openLineBy (openTerm "\n") [
         Line True [ Info (Range 0 1) mempty :< Leaf "" ]
       ] `shouldBe` Nothing

From 09034a8fdaa2b5e64546c6daaca5c7c2e9205761 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 20:39:51 -0500
Subject: [PATCH 098/259] We never need to adjoin leaf lines.

---
 src/Split.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index c5999b1fe..7454c36f1 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -151,7 +151,7 @@ diffToRows (Pure (Replace a b)) _ before after = (replacedRows, (leftRange, righ
 -- | Takes a term and a source and returns a list of lines and their range within source.
 splitTermByLines :: Term a Info -> String -> ([Line (Term a Info)], Range)
 splitTermByLines (Info range categories :< syntax) source = flip (,) range $ case syntax of
-  Leaf a -> adjoin $ contextLines (Leaf a) range source
+  Leaf a -> contextLines (Leaf a) range source
   Indexed children -> adjoinTermLines Indexed children
   Fixed children -> adjoinTermLines Fixed children
   Keyed children -> adjoinTermLines Keyed children

From 45cf3683565156747fd3b8dba60e299972f9aea5 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 20:46:03 -0500
Subject: [PATCH 099/259] =?UTF-8?q?Rename=20adjoinTermLines=20=E2=86=92=20?=
 =?UTF-8?q?adjoinChildLines.?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 src/Split.hs | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 7454c36f1..068493fab 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -152,11 +152,11 @@ diffToRows (Pure (Replace a b)) _ before after = (replacedRows, (leftRange, righ
 splitTermByLines :: Term a Info -> String -> ([Line (Term a Info)], Range)
 splitTermByLines (Info range categories :< syntax) source = flip (,) range $ case syntax of
   Leaf a -> contextLines (Leaf a) range source
-  Indexed children -> adjoinTermLines Indexed children
-  Fixed children -> adjoinTermLines Fixed children
-  Keyed children -> adjoinTermLines Keyed children
+  Indexed children -> adjoinChildLines Indexed children
+  Fixed children -> adjoinChildLines Fixed children
+  Keyed children -> adjoinChildLines Keyed children
   where adjoin = reverse . foldl (adjoinLinesBy $ openTerm source) []
-        adjoinTermLines constructor children = let (lines, previous) = foldl (childLines $ constructor mempty) ([], start range) children in
+        adjoinChildLines constructor children = let (lines, previous) = foldl (childLines $ constructor mempty) ([], start range) children in
           adjoin $ lines ++ contextLines (constructor mempty) (Range previous $ end range) source
         contextLines constructor range source = Line True . (:[]) . (:< constructor) . (`Info` categories) <$> actualLineRanges range source
         childLines constructor (lines, previous) child = let (childLines, childRange) = splitTermByLines child source in

From 739e9992338a5776fe56b35638deabc3c7c40e00 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 20:48:55 -0500
Subject: [PATCH 100/259] Extract a contextRows binding.

---
 src/Split.hs | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index 068493fab..3106bb10b 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -183,8 +183,9 @@ termToLines (Info range categories :< syntax) source = (rows syntax, range)
 
 splitAnnotatedByLines :: (String, String) -> (Range, Range) -> (Set.Set Category, Set.Set Category) -> Syntax a (Diff a Info) -> [Row (Term a Info)]
 splitAnnotatedByLines sources ranges categories syntax = case syntax of
-  Leaf a -> zipWithDefaults Row EmptyLine EmptyLine (contextLines (Leaf a) (fst ranges) (fst categories) (fst sources)) (contextLines (Leaf a) (snd ranges) (snd categories) (snd sources))
+  Leaf a -> contextRows (Leaf a) ranges categories sources
   where contextLines constructor range categories source = Line False . (:[]) . (:< constructor) . (`Info` categories) <$> actualLineRanges range source
+        contextRows constructor ranges categoriess sources = zipWithDefaults Row EmptyLine EmptyLine (contextLines (Leaf a) (fst ranges) (fst categories) (fst sources)) (contextLines (Leaf a) (snd ranges) (snd categories) (snd sources))
 
 -- | Given an Annotated and before/after strings, returns a list of `Row`s representing the newline-separated diff.
 annotatedToRows :: Annotated a (Info, Info) (Diff a Info) -> String -> String -> [Row HTML]

From a78ae5a8de7a3e55d1d7049ca6dc2532d2cdc1c8 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 21:00:53 -0500
Subject: [PATCH 101/259] =?UTF-8?q?Correct=20the=20indentation=20of=20Line?=
 =?UTF-8?q?=E2=80=99s=20Monoid=20instance.?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 src/Split.hs | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 3106bb10b..3b288b350 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -124,10 +124,10 @@ instance Show a => Show (Line a) where
   show EmptyLine = "EmptyLine"
 
 instance Monoid (Line a) where
- mempty = EmptyLine
- mappend EmptyLine line = line
- mappend line EmptyLine = line
- mappend (Line c1 xs) (Line c2 ys) = Line (c1 || c2) (xs <> ys)
+  mempty = EmptyLine
+  mappend EmptyLine line = line
+  mappend line EmptyLine = line
+  mappend (Line c1 xs) (Line c2 ys) = Line (c1 || c2) (xs <> ys)
 
 diffToRows :: Diff a Info -> (Int, Int) -> String -> String -> ([Row HTML], (Range, Range))
 diffToRows (Free annotated@(Annotated (Info left _, Info right _) _)) _ before after = (annotatedToRows annotated before after, (left, right))

From 2d383b57c8cc8f95f268aba3de44c0fdd9681c6d Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 22:26:26 -0500
Subject: [PATCH 102/259] Abbreviate sumRows.

---
 src/Split.hs | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 3b288b350..401b1a23d 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -208,11 +208,8 @@ annotatedToRows (Annotated (Info left leftCategories, Info right rightCategories
     appendRemainder (rows, previousIndices) = reverse . foldl (adjoinRowsBy openElement) [] $ rows ++ contextRows (ends ranges) previousIndices sources
     starts (left, right) = (start left, start right)
     ends (left, right) = (end left, end right)
-    sumRows (rows, previousIndices) child = (allRows, ends childRanges)
-      where
-        separatorRows = contextRows (starts childRanges) previousIndices sources
-        allRows = rows ++ separatorRows ++ childRows
-        (childRows, childRanges) = diffToRows child previousIndices before after
+    sumRows (rows, previousIndices) child = let (childRows, childRanges) = diffToRows child previousIndices before after in
+      (rows ++ contextRows (starts childRanges) previousIndices sources ++ childRows, ends childRanges)
 
 contextRows :: (Int, Int) -> (Int, Int) -> (String, String) -> [Row HTML]
 contextRows childIndices previousIndices sources = zipWithMaybe rowFromMaybeRows leftElements rightElements

From aa42b88df50fef3fb2e4a7192277275263a7ad70 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 22:26:43 -0500
Subject: [PATCH 103/259] adjoinRowsBy takes two different adjoining functions.

---
 src/Split.hs | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 401b1a23d..2fea6e2ad 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -205,7 +205,7 @@ annotatedToRows (Annotated (Info left leftCategories, Info right rightCategories
     ranges = (left, right)
     sources = (before, after)
     childRows = appendRemainder . foldl sumRows ([], starts ranges)
-    appendRemainder (rows, previousIndices) = reverse . foldl (adjoinRowsBy openElement) [] $ rows ++ contextRows (ends ranges) previousIndices sources
+    appendRemainder (rows, previousIndices) = reverse . foldl (adjoinRowsBy openElement openElement) [] $ rows ++ contextRows (ends ranges) previousIndices sources
     starts (left, right) = (start left, start right)
     ends (left, right) = (end left, end right)
     sumRows (rows, previousIndices) child = let (childRows, childRanges) = diffToRows child previousIndices before after in
@@ -233,28 +233,28 @@ rowFromMaybeRows a b = Row (maybe EmptyLine (Line False . (:[])) a) (maybe Empty
 maybeLast :: Foldable f => f a -> Maybe a
 maybeLast = foldl (flip $ const . Just) Nothing
 
-adjoinRowsBy :: (a -> Maybe a) -> [Row a] -> Row a -> [Row a]
-adjoinRowsBy _ [] row = [row]
+adjoinRowsBy :: (a -> Maybe a) -> (a -> Maybe a) -> [Row a] -> Row a -> [Row a]
+adjoinRowsBy _ _ [] row = [row]
 
-adjoinRowsBy f rows (Row left' right') | Just _ <- openLineBy f $ unLeft <$> rows, Just _ <- openLineBy f $ unRight <$> rows = zipWith Row lefts rights
+adjoinRowsBy f g rows (Row left' right') | Just _ <- openLineBy f $ unLeft <$> rows, Just _ <- openLineBy g $ unRight <$> rows = zipWith Row lefts rights
   where lefts = adjoinLinesBy f (unLeft <$> rows) left'
-        rights = adjoinLinesBy f (unRight <$> rows) right'
+        rights = adjoinLinesBy g (unRight <$> rows) right'
 
-adjoinRowsBy f rows (Row left' right') | Just _ <- openLineBy f $ unLeft <$> rows = case right' of
+adjoinRowsBy f _ rows (Row left' right') | Just _ <- openLineBy f $ unLeft <$> rows = case right' of
   EmptyLine -> rest
   _ -> Row EmptyLine right' : rest
   where rest = zipWith Row lefts rights
         lefts = adjoinLinesBy f (unLeft <$> rows) left'
         rights = unRight <$> rows
 
-adjoinRowsBy f rows (Row left' right') | Just _ <- openLineBy f $ unRight <$> rows = case left' of
+adjoinRowsBy _ g rows (Row left' right') | Just _ <- openLineBy g $ unRight <$> rows = case left' of
   EmptyLine -> rest
   _ -> Row left' EmptyLine : rest
   where rest = zipWith Row lefts rights
         lefts = unLeft <$> rows
-        rights = adjoinLinesBy f (unRight <$> rows) right'
+        rights = adjoinLinesBy g (unRight <$> rows) right'
 
-adjoinRowsBy _ rows row = row : rows
+adjoinRowsBy _ _ rows row = row : rows
 
 openElement :: HTML -> Maybe HTML
 openElement Break = Nothing

From 27c66b558880cc5289abae9b4a84f6d9f21cf4a4 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 22:27:10 -0500
Subject: [PATCH 104/259] Add an `adjoin` binding.

---
 src/Split.hs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/Split.hs b/src/Split.hs
index 2fea6e2ad..5b1f77a1d 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -187,6 +187,8 @@ splitAnnotatedByLines sources ranges categories syntax = case syntax of
   where contextLines constructor range categories source = Line False . (:[]) . (:< constructor) . (`Info` categories) <$> actualLineRanges range source
         contextRows constructor ranges categoriess sources = zipWithDefaults Row EmptyLine EmptyLine (contextLines (Leaf a) (fst ranges) (fst categories) (fst sources)) (contextLines (Leaf a) (snd ranges) (snd categories) (snd sources))
 
+        adjoin = reverse . foldl (adjoinRowsBy (openTerm $ fst sources) (openTerm $ snd sources)) []
+
 -- | Given an Annotated and before/after strings, returns a list of `Row`s representing the newline-separated diff.
 annotatedToRows :: Annotated a (Info, Info) (Diff a Info) -> String -> String -> [Row HTML]
 annotatedToRows (Annotated (Info left leftCategories, Info right rightCategories) syntax) before after = rows syntax

From 5f7b33db85cbb867a2444acba566f83b683357de Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 22:27:19 -0500
Subject: [PATCH 105/259] Add some range-handling bindings.

---
 src/Split.hs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/Split.hs b/src/Split.hs
index 5b1f77a1d..4d714804c 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -189,6 +189,10 @@ splitAnnotatedByLines sources ranges categories syntax = case syntax of
 
         adjoin = reverse . foldl (adjoinRowsBy (openTerm $ fst sources) (openTerm $ snd sources)) []
 
+        starts (left, right) = (start left, start right)
+        ends (left, right) = (end left, end right)
+        makeRanges (leftStart, rightStart) (leftEnd, rightEnd) = (Range leftStart leftEnd, Range rightStart rightEnd)
+
 -- | Given an Annotated and before/after strings, returns a list of `Row`s representing the newline-separated diff.
 annotatedToRows :: Annotated a (Info, Info) (Diff a Info) -> String -> String -> [Row HTML]
 annotatedToRows (Annotated (Info left leftCategories, Info right rightCategories) syntax) before after = rows syntax

From b9ed84b7b6e062f9be33824d7164c4caf3fb443c Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 22:34:08 -0500
Subject: [PATCH 106/259] Pass categories to contextLines explicitly.

---
 src/Split.hs | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 4d714804c..4d2b1f4e4 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -151,16 +151,16 @@ diffToRows (Pure (Replace a b)) _ before after = (replacedRows, (leftRange, righ
 -- | Takes a term and a source and returns a list of lines and their range within source.
 splitTermByLines :: Term a Info -> String -> ([Line (Term a Info)], Range)
 splitTermByLines (Info range categories :< syntax) source = flip (,) range $ case syntax of
-  Leaf a -> contextLines (Leaf a) range source
+  Leaf a -> contextLines (Leaf a) range categories source
   Indexed children -> adjoinChildLines Indexed children
   Fixed children -> adjoinChildLines Fixed children
   Keyed children -> adjoinChildLines Keyed children
   where adjoin = reverse . foldl (adjoinLinesBy $ openTerm source) []
         adjoinChildLines constructor children = let (lines, previous) = foldl (childLines $ constructor mempty) ([], start range) children in
-          adjoin $ lines ++ contextLines (constructor mempty) (Range previous $ end range) source
-        contextLines constructor range source = Line True . (:[]) . (:< constructor) . (`Info` categories) <$> actualLineRanges range source
+          adjoin $ lines ++ contextLines (constructor mempty) (Range previous $ end range) categories source
+        contextLines constructor range categories source = Line True . (:[]) . (:< constructor) . (`Info` categories) <$> actualLineRanges range source
         childLines constructor (lines, previous) child = let (childLines, childRange) = splitTermByLines child source in
-          (adjoin $ lines ++ contextLines constructor (Range previous $ start childRange) source ++ childLines, end childRange)
+          (adjoin $ lines ++ contextLines constructor (Range previous $ start childRange) categories source ++ childLines, end childRange)
 
 -- | Takes a term and a source and returns a list of lines and their range within source.
 termToLines :: Term a Info -> String -> ([Line HTML], Range)

From f43bbe415bf2191d88a21aad0bb0f2df659697fb Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 22:34:20 -0500
Subject: [PATCH 107/259] Add a global contextLines definition.

---
 src/Split.hs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/Split.hs b/src/Split.hs
index 4d2b1f4e4..e5be38d20 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -217,6 +217,9 @@ annotatedToRows (Annotated (Info left leftCategories, Info right rightCategories
     sumRows (rows, previousIndices) child = let (childRows, childRanges) = diffToRows child previousIndices before after in
       (rows ++ contextRows (starts childRanges) previousIndices sources ++ childRows, ends childRanges)
 
+contextLines :: Syntax a (Term a Info) -> Range -> Set.Set Category -> String -> [Line (Term a Info)]
+contextLines constructor range categories source = Line True . (:[]) . (:< constructor) . (`Info` categories) <$> actualLineRanges range source
+
 contextRows :: (Int, Int) -> (Int, Int) -> (String, String) -> [Row HTML]
 contextRows childIndices previousIndices sources = zipWithMaybe rowFromMaybeRows leftElements rightElements
   where

From ac01a7939c0c0aa13dca9e32a66028bebb4932c0 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 22:34:47 -0500
Subject: [PATCH 108/259] Use the global contextLines definition in
 splitTermByLines.

---
 src/Split.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index e5be38d20..003fcb81e 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -158,7 +158,7 @@ splitTermByLines (Info range categories :< syntax) source = flip (,) range $ cas
   where adjoin = reverse . foldl (adjoinLinesBy $ openTerm source) []
         adjoinChildLines constructor children = let (lines, previous) = foldl (childLines $ constructor mempty) ([], start range) children in
           adjoin $ lines ++ contextLines (constructor mempty) (Range previous $ end range) categories source
-        contextLines constructor range categories source = Line True . (:[]) . (:< constructor) . (`Info` categories) <$> actualLineRanges range source
+
         childLines constructor (lines, previous) child = let (childLines, childRange) = splitTermByLines child source in
           (adjoin $ lines ++ contextLines constructor (Range previous $ start childRange) categories source ++ childLines, end childRange)
 

From 9dba0887c850f9c702397307756a280b489a722e Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 22:37:38 -0500
Subject: [PATCH 109/259] Remove the local contextLines binding from
 splitAnnotatedByLines.

---
 src/Split.hs | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 003fcb81e..485cb8d2d 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -184,8 +184,7 @@ termToLines (Info range categories :< syntax) source = (rows syntax, range)
 splitAnnotatedByLines :: (String, String) -> (Range, Range) -> (Set.Set Category, Set.Set Category) -> Syntax a (Diff a Info) -> [Row (Term a Info)]
 splitAnnotatedByLines sources ranges categories syntax = case syntax of
   Leaf a -> contextRows (Leaf a) ranges categories sources
-  where contextLines constructor range categories source = Line False . (:[]) . (:< constructor) . (`Info` categories) <$> actualLineRanges range source
-        contextRows constructor ranges categoriess sources = zipWithDefaults Row EmptyLine EmptyLine (contextLines (Leaf a) (fst ranges) (fst categories) (fst sources)) (contextLines (Leaf a) (snd ranges) (snd categories) (snd sources))
+  where contextRows constructor ranges categoriess sources = zipWithDefaults Row EmptyLine EmptyLine (contextLines (Leaf a) (fst ranges) (fst categories) (fst sources)) (contextLines (Leaf a) (snd ranges) (snd categories) (snd sources))
 
         adjoin = reverse . foldl (adjoinRowsBy (openTerm $ fst sources) (openTerm $ snd sources)) []
 

From 6c877fd0424db0f410b047991eb2ee01fbe4c4c0 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 22:41:19 -0500
Subject: [PATCH 110/259] =?UTF-8?q?contextRows=20uses=20the=20constructor?=
 =?UTF-8?q?=20it=E2=80=99s=20passed.?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 src/Split.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index 485cb8d2d..44f8571fd 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -184,7 +184,7 @@ termToLines (Info range categories :< syntax) source = (rows syntax, range)
 splitAnnotatedByLines :: (String, String) -> (Range, Range) -> (Set.Set Category, Set.Set Category) -> Syntax a (Diff a Info) -> [Row (Term a Info)]
 splitAnnotatedByLines sources ranges categories syntax = case syntax of
   Leaf a -> contextRows (Leaf a) ranges categories sources
-  where contextRows constructor ranges categoriess sources = zipWithDefaults Row EmptyLine EmptyLine (contextLines (Leaf a) (fst ranges) (fst categories) (fst sources)) (contextLines (Leaf a) (snd ranges) (snd categories) (snd sources))
+  where contextRows constructor ranges categories sources = zipWithDefaults Row EmptyLine EmptyLine (contextLines constructor (fst ranges) (fst categories) (fst sources)) (contextLines constructor (snd ranges) (snd categories) (snd sources))
 
         adjoin = reverse . foldl (adjoinRowsBy (openTerm $ fst sources) (openTerm $ snd sources)) []
 

From 08c9b842533ebc7625c8327d0a5b5c78b56578ca Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 22:42:08 -0500
Subject: [PATCH 111/259] Stub in splitDiffByLines over Free values.

---
 src/Split.hs | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/Split.hs b/src/Split.hs
index 44f8571fd..fe64cfd75 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -129,6 +129,11 @@ instance Monoid (Line a) where
   mappend line EmptyLine = line
   mappend (Line c1 xs) (Line c2 ys) = Line (c1 || c2) (xs <> ys)
 
+splitDiffByLines :: Diff a Info -> (Int, Int) -> (String, String) -> ([Row (Term a Info)], (Range, Range))
+splitDiffByLines (Free (Annotated annotation syntax)) _ sources = (splitAnnotatedByLines sources (ranges annotation) (categories annotation) syntax, ranges annotation)
+  where categories (Info _ left, Info _ right) = (left, right)
+        ranges (Info left _, Info right _) = (left, right)
+
 diffToRows :: Diff a Info -> (Int, Int) -> String -> String -> ([Row HTML], (Range, Range))
 diffToRows (Free annotated@(Annotated (Info left _, Info right _) _)) _ before after = (annotatedToRows annotated before after, (left, right))
 diffToRows (Pure (Insert term)) (previousIndex, _) _ after = (rowWithInsertedLine <$> afterLines, (Range previousIndex previousIndex, range))

From 7414c09c1873afd5edc3e609b3598ad1e61ab097 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 22:42:27 -0500
Subject: [PATCH 112/259] Compute the rows for child diffs.

---
 src/Split.hs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/Split.hs b/src/Split.hs
index fe64cfd75..334804c4e 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -193,6 +193,9 @@ splitAnnotatedByLines sources ranges categories syntax = case syntax of
 
         adjoin = reverse . foldl (adjoinRowsBy (openTerm $ fst sources) (openTerm $ snd sources)) []
 
+        childRows constructor (rows, previous) child = let (childRows, childRanges) = splitDiffByLines child previous sources in
+          (adjoin $ rows ++ contextRows constructor (makeRanges previous (starts childRanges)) categories sources ++ childRows, ends childRanges)
+
         starts (left, right) = (start left, start right)
         ends (left, right) = (end left, end right)
         makeRanges (leftStart, rightStart) (leftEnd, rightEnd) = (Range leftStart leftEnd, Range rightStart rightEnd)

From 97ec8a2e94eca40a564916a892a1e3ca8b318bbf Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 22:42:58 -0500
Subject: [PATCH 113/259] Compute the rows to the end of the range.

---
 src/Split.hs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/Split.hs b/src/Split.hs
index 334804c4e..2ff861e19 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -192,6 +192,8 @@ splitAnnotatedByLines sources ranges categories syntax = case syntax of
   where contextRows constructor ranges categories sources = zipWithDefaults Row EmptyLine EmptyLine (contextLines constructor (fst ranges) (fst categories) (fst sources)) (contextLines constructor (snd ranges) (snd categories) (snd sources))
 
         adjoin = reverse . foldl (adjoinRowsBy (openTerm $ fst sources) (openTerm $ snd sources)) []
+        adjoinChildRows constructor children = let (rows, previous) = foldl (childRows $ constructor mempty) ([], starts ranges) children in
+          adjoin $ rows ++ contextRows (constructor mempty) (makeRanges previous (ends ranges)) categories sources
 
         childRows constructor (rows, previous) child = let (childRows, childRanges) = splitDiffByLines child previous sources in
           (adjoin $ rows ++ contextRows constructor (makeRanges previous (starts childRanges)) categories sources ++ childRows, ends childRanges)

From cdc01b499543508fb95a794c6a29f00b06e982ca Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 22:43:19 -0500
Subject: [PATCH 114/259] Define splitAnnotatedByLines over Indexed diffs.

---
 src/Split.hs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/Split.hs b/src/Split.hs
index 2ff861e19..3ae9e9ef7 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -189,6 +189,7 @@ termToLines (Info range categories :< syntax) source = (rows syntax, range)
 splitAnnotatedByLines :: (String, String) -> (Range, Range) -> (Set.Set Category, Set.Set Category) -> Syntax a (Diff a Info) -> [Row (Term a Info)]
 splitAnnotatedByLines sources ranges categories syntax = case syntax of
   Leaf a -> contextRows (Leaf a) ranges categories sources
+  Indexed children -> adjoinChildRows Indexed children
   where contextRows constructor ranges categories sources = zipWithDefaults Row EmptyLine EmptyLine (contextLines constructor (fst ranges) (fst categories) (fst sources)) (contextLines constructor (snd ranges) (snd categories) (snd sources))
 
         adjoin = reverse . foldl (adjoinRowsBy (openTerm $ fst sources) (openTerm $ snd sources)) []

From e78f9cdbcff6da3187a5269d89a86111503cb2be Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 22:43:49 -0500
Subject: [PATCH 115/259] Define splitAnnotatedByLines over Fixed diffs.

---
 src/Split.hs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/Split.hs b/src/Split.hs
index 3ae9e9ef7..c05ff7bb8 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -190,6 +190,7 @@ splitAnnotatedByLines :: (String, String) -> (Range, Range) -> (Set.Set Category
 splitAnnotatedByLines sources ranges categories syntax = case syntax of
   Leaf a -> contextRows (Leaf a) ranges categories sources
   Indexed children -> adjoinChildRows Indexed children
+  Fixed children -> adjoinChildRows Fixed children
   where contextRows constructor ranges categories sources = zipWithDefaults Row EmptyLine EmptyLine (contextLines constructor (fst ranges) (fst categories) (fst sources)) (contextLines constructor (snd ranges) (snd categories) (snd sources))
 
         adjoin = reverse . foldl (adjoinRowsBy (openTerm $ fst sources) (openTerm $ snd sources)) []

From cff017ccddac5e06c5b5c4c33f5c118fc576e8e7 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 22:45:21 -0500
Subject: [PATCH 116/259] Define splitAnnotatedByLines over Keyed diffs.

---
 src/Split.hs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/Split.hs b/src/Split.hs
index c05ff7bb8..fc68212bb 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -191,6 +191,7 @@ splitAnnotatedByLines sources ranges categories syntax = case syntax of
   Leaf a -> contextRows (Leaf a) ranges categories sources
   Indexed children -> adjoinChildRows Indexed children
   Fixed children -> adjoinChildRows Fixed children
+  Keyed children -> adjoinChildRows Keyed children
   where contextRows constructor ranges categories sources = zipWithDefaults Row EmptyLine EmptyLine (contextLines constructor (fst ranges) (fst categories) (fst sources)) (contextLines constructor (snd ranges) (snd categories) (snd sources))
 
         adjoin = reverse . foldl (adjoinRowsBy (openTerm $ fst sources) (openTerm $ snd sources)) []

From cf13cb6488b2e254a32d06f8cde2a6b5f86d555a Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 22:48:59 -0500
Subject: [PATCH 117/259] Define splitDiffByLines by pattern matching.

---
 src/Split.hs | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index fc68212bb..1666465b2 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -130,7 +130,8 @@ instance Monoid (Line a) where
   mappend (Line c1 xs) (Line c2 ys) = Line (c1 || c2) (xs <> ys)
 
 splitDiffByLines :: Diff a Info -> (Int, Int) -> (String, String) -> ([Row (Term a Info)], (Range, Range))
-splitDiffByLines (Free (Annotated annotation syntax)) _ sources = (splitAnnotatedByLines sources (ranges annotation) (categories annotation) syntax, ranges annotation)
+splitDiffByLines diff _ sources = case diff of
+  Free (Annotated annotation syntax) -> (splitAnnotatedByLines sources (ranges annotation) (categories annotation) syntax, ranges annotation)
   where categories (Info _ left, Info _ right) = (left, right)
         ranges (Info left _, Info right _) = (left, right)
 

From cea5193999deeb34a63d74545fd60d69f05b0694 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 22:58:12 -0500
Subject: [PATCH 118/259] Define splitDiffByLines over Insert patches.

---
 src/Split.hs | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index 1666465b2..56762eb98 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -130,8 +130,10 @@ instance Monoid (Line a) where
   mappend (Line c1 xs) (Line c2 ys) = Line (c1 || c2) (xs <> ys)
 
 splitDiffByLines :: Diff a Info -> (Int, Int) -> (String, String) -> ([Row (Term a Info)], (Range, Range))
-splitDiffByLines diff _ sources = case diff of
+splitDiffByLines diff (prevLeft, prevRight) sources = case diff of
   Free (Annotated annotation syntax) -> (splitAnnotatedByLines sources (ranges annotation) (categories annotation) syntax, ranges annotation)
+  Pure (Insert term) -> let (lines, range) = splitTermByLines term (snd sources) in
+    (Row EmptyLine <$> lines, (Range prevLeft prevLeft, range))
   where categories (Info _ left, Info _ right) = (left, right)
         ranges (Info left _, Info right _) = (left, right)
 

From c2a754bfa0f2b2319fca918b64c979f83d751459 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 22:59:34 -0500
Subject: [PATCH 119/259] Define splitDiffByLines over Delete patches.

---
 src/Split.hs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/Split.hs b/src/Split.hs
index 56762eb98..5bd6781e1 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -134,6 +134,8 @@ splitDiffByLines diff (prevLeft, prevRight) sources = case diff of
   Free (Annotated annotation syntax) -> (splitAnnotatedByLines sources (ranges annotation) (categories annotation) syntax, ranges annotation)
   Pure (Insert term) -> let (lines, range) = splitTermByLines term (snd sources) in
     (Row EmptyLine <$> lines, (Range prevLeft prevLeft, range))
+  Pure (Delete term) -> let (lines, range) = splitTermByLines term (snd sources) in
+    (flip Row EmptyLine <$> lines, (range, Range prevRight prevRight))
   where categories (Info _ left, Info _ right) = (left, right)
         ranges (Info left _, Info right _) = (left, right)
 

From c471a5e7799b6e3fc7639a61c205dbbb579fee99 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 23:06:18 -0500
Subject: [PATCH 120/259] Correct the source used in the Delete case.

---
 src/Split.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index 5bd6781e1..8736b3c4a 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -134,7 +134,7 @@ splitDiffByLines diff (prevLeft, prevRight) sources = case diff of
   Free (Annotated annotation syntax) -> (splitAnnotatedByLines sources (ranges annotation) (categories annotation) syntax, ranges annotation)
   Pure (Insert term) -> let (lines, range) = splitTermByLines term (snd sources) in
     (Row EmptyLine <$> lines, (Range prevLeft prevLeft, range))
-  Pure (Delete term) -> let (lines, range) = splitTermByLines term (snd sources) in
+  Pure (Delete term) -> let (lines, range) = splitTermByLines term (fst sources) in
     (flip Row EmptyLine <$> lines, (range, Range prevRight prevRight))
   where categories (Info _ left, Info _ right) = (left, right)
         ranges (Info left _, Info right _) = (left, right)

From c7e5690da4731f4ca95aaa63086a860732499466 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 23:06:27 -0500
Subject: [PATCH 121/259] Define splitDiffByLines over Replace patches.

---
 src/Split.hs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/Split.hs b/src/Split.hs
index 8736b3c4a..1b482fc68 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -136,6 +136,9 @@ splitDiffByLines diff (prevLeft, prevRight) sources = case diff of
     (Row EmptyLine <$> lines, (Range prevLeft prevLeft, range))
   Pure (Delete term) -> let (lines, range) = splitTermByLines term (fst sources) in
     (flip Row EmptyLine <$> lines, (range, Range prevRight prevRight))
+  Pure (Replace leftTerm rightTerm) -> let (leftLines, leftRange) = splitTermByLines leftTerm (fst sources)
+                                           (rightLines, rightRange) = splitTermByLines rightTerm (snd sources) in
+                                           (zipWithDefaults Row EmptyLine EmptyLine leftLines rightLines, (leftRange, rightRange))
   where categories (Info _ left, Info _ right) = (left, right)
         ranges (Info left _, Info right _) = (left, right)
 

From 597fe099bcaadaf911a8a24162d519e7f7c5e8a5 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 23:09:14 -0500
Subject: [PATCH 122/259] Pass an additional open predicate to adjoinRowsBy.

---
 test/SplitSpec.hs | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 8de15986b..95dcfea02 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -115,24 +115,24 @@ spec = do
 
   describe "adjoinRowsBy" $ do
     prop "is identity on top of no rows" $
-      \ a -> adjoinRowsBy openElement [] a == [ a ]
+      \ a -> adjoinRowsBy openElement openElement [] a == [ a ]
 
     prop "appends onto open rows" $
       forAll ((arbitrary `suchThat` isOpen) >>= \ a -> (,) a <$> (arbitrary `suchThat` isOpen)) $
         \ (a@(Row (Line ac1 as1) (Line bc1 bs1)), b@(Row (Line ac2 as2) (Line bc2 bs2))) ->
-          adjoinRowsBy openElement [ a ] b `shouldBe` [ Row (Line (ac1 || ac2) $ as1 ++ as2) (Line (bc1 || bc2) $ bs1 ++ bs2) ]
+          adjoinRowsBy openElement openElement [ a ] b `shouldBe` [ Row (Line (ac1 || ac2) $ as1 ++ as2) (Line (bc1 || bc2) $ bs1 ++ bs2) ]
 
     prop "does not append onto closed rows" $
       forAll ((arbitrary `suchThat` isClosed) >>= \ a -> (,) a <$> (arbitrary `suchThat` isClosed)) $
-        \ (a, b) -> adjoinRowsBy openElement [ a ] b `shouldBe` [ b, a ]
+        \ (a, b) -> adjoinRowsBy openElement openElement [ a ] b `shouldBe` [ b, a ]
 
     prop "does not promote elements through empty lines onto closed lines" $
       forAll ((arbitrary `suchThat` isClosed) >>= \ a -> (,) a <$> (arbitrary `suchThat` isClosed)) $
-        \ (a, b) -> adjoinRowsBy openElement [ Row EmptyLine EmptyLine, a ] b `shouldBe` [ b, Row EmptyLine EmptyLine, a ]
+        \ (a, b) -> adjoinRowsBy openElement openElement [ Row EmptyLine EmptyLine, a ] b `shouldBe` [ b, Row EmptyLine EmptyLine, a ]
 
     prop "promotes elements through empty lines onto open lines" $
       forAll ((arbitrary `suchThat` isOpen) >>= \ a -> (,) a <$> (arbitrary `suchThat` isOpen)) $
-        \ (a, b) -> adjoinRowsBy openElement [ Row EmptyLine EmptyLine, a ] b `shouldBe` Row EmptyLine EmptyLine : adjoinRowsBy openElement [ a ] b
+        \ (a, b) -> adjoinRowsBy openElement openElement [ Row EmptyLine EmptyLine, a ] b `shouldBe` Row EmptyLine EmptyLine : adjoinRowsBy openElement openElement [ a ] b
 
   describe "termToLines" $ do
     it "splits multi-line terms into multiple lines" $

From eb12d72c36937fd643c7a643e8fa5f74441c3630 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 23:42:54 -0500
Subject: [PATCH 123/259] Line is a Functor.

---
 src/Split.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index 1b482fc68..629511c13 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -113,7 +113,7 @@ instance ToMarkup a => ToMarkup (Line a) where
 data Line a =
   Line Bool [a]
   | EmptyLine
-  deriving Eq
+  deriving (Eq, Functor)
 
 unLine :: Line a -> [a]
 unLine EmptyLine = []

From b4cd2c14c49491522b1f81930d9982966ff56e48 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Mon, 21 Dec 2015 23:42:57 -0500
Subject: [PATCH 124/259] Row is a Functor.

---
 src/Split.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index 629511c13..e0015babf 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -84,7 +84,7 @@ split diff before after = return . renderHtml
 
 
 data Row a = Row { unLeft :: Line a, unRight :: Line a }
-  deriving Eq
+  deriving (Eq, Functor)
 
 instance Show a => Show (Row a) where
   show (Row left right) = "\n" ++ show left ++ " | " ++ show right

From ffbd9b5b51a12dfaabbed6b5079ddee00694b3fc Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 09:37:41 -0500
Subject: [PATCH 125/259] Add a type synonym for a split diff.

---
 src/Split.hs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/Split.hs b/src/Split.hs
index e0015babf..1ff1460d5 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -129,6 +129,9 @@ instance Monoid (Line a) where
   mappend line EmptyLine = line
   mappend (Line c1 xs) (Line c2 ys) = Line (c1 || c2) (xs <> ys)
 
+-- | A diff with only one side’s annotations.
+type SplitDiff leaf annotation = Free (Annotated leaf annotation) (Patch (Term leaf annotation))
+
 splitDiffByLines :: Diff a Info -> (Int, Int) -> (String, String) -> ([Row (Term a Info)], (Range, Range))
 splitDiffByLines diff (prevLeft, prevRight) sources = case diff of
   Free (Annotated annotation syntax) -> (splitAnnotatedByLines sources (ranges annotation) (categories annotation) syntax, ranges annotation)

From 3368857e2b69ab80cef8728ed6a2dca13f780a5a Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 09:52:55 -0500
Subject: [PATCH 126/259] Represent `SplitDiff` patches using `Maybe`.

---
 src/Split.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index 1ff1460d5..2aa80303e 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -130,7 +130,7 @@ instance Monoid (Line a) where
   mappend (Line c1 xs) (Line c2 ys) = Line (c1 || c2) (xs <> ys)
 
 -- | A diff with only one side’s annotations.
-type SplitDiff leaf annotation = Free (Annotated leaf annotation) (Patch (Term leaf annotation))
+type SplitDiff leaf annotation = Free (Annotated leaf annotation) (Maybe (Term leaf annotation))
 
 splitDiffByLines :: Diff a Info -> (Int, Int) -> (String, String) -> ([Row (Term a Info)], (Range, Range))
 splitDiffByLines diff (prevLeft, prevRight) sources = case diff of

From b1c5e3e305715178a68fe8ffc967867b6ee628ec Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 09:54:40 -0500
Subject: [PATCH 127/259] Represent `SplitDiff` patches totally.

---
 src/Split.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index 2aa80303e..19eb2716c 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -130,7 +130,7 @@ instance Monoid (Line a) where
   mappend (Line c1 xs) (Line c2 ys) = Line (c1 || c2) (xs <> ys)
 
 -- | A diff with only one side’s annotations.
-type SplitDiff leaf annotation = Free (Annotated leaf annotation) (Maybe (Term leaf annotation))
+type SplitDiff leaf annotation = Free (Annotated leaf annotation) (Term leaf annotation)
 
 splitDiffByLines :: Diff a Info -> (Int, Int) -> (String, String) -> ([Row (Term a Info)], (Range, Range))
 splitDiffByLines diff (prevLeft, prevRight) sources = case diff of

From 37dcb3adead701b3d2cda207f36d9ee23cb856c5 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 09:56:11 -0500
Subject: [PATCH 128/259] Define an openDiff function over SplitDiff.

---
 src/Split.hs | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/Split.hs b/src/Split.hs
index 19eb2716c..d4edf26c6 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -300,6 +300,12 @@ openTerm source term@(Info range _ :< _) = case (source !!) <$> maybeLastIndex r
   Just '\n' -> Nothing
   _ -> Just term
 
+openDiff :: String -> SplitDiff a Info -> Maybe (SplitDiff a Info)
+openDiff source diff@(Free (Annotated (Info range _) _)) = case (source !!) <$> maybeLastIndex range of
+  Just '\n' -> Nothing
+  _ -> Just diff
+openDiff source diff@(Pure term) = const diff <$> openTerm source term
+
 openLineBy :: (a -> Maybe a) -> [Line a] -> Maybe (Line a)
 openLineBy _ [] = Nothing
 openLineBy f (EmptyLine : rest) = openLineBy f rest

From fbe3b8dbeb1d0589f1a0ceb7867f55b852bcbf36 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 09:58:07 -0500
Subject: [PATCH 129/259] Define openTerm & openDiff in terms of an openRange
 function.

---
 src/Split.hs | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index d4edf26c6..cc5fb42e9 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -295,15 +295,16 @@ openElement (Dl _ elements) = openElement =<< maybeLast elements
 openElement (Div _ elements) = openElement =<< maybeLast elements
 openElement h = Just h
 
-openTerm :: String -> Term a Info -> Maybe (Term a Info)
-openTerm source term@(Info range _ :< _) = case (source !!) <$> maybeLastIndex range of
+openRange :: String -> Range -> Maybe Range
+openRange source range = case (source !!) <$> maybeLastIndex range of
   Just '\n' -> Nothing
-  _ -> Just term
+  _ -> Just range
+
+openTerm :: String -> Term a Info -> Maybe (Term a Info)
+openTerm source term@(Info range _ :< _) = const term <$> openRange source range
 
 openDiff :: String -> SplitDiff a Info -> Maybe (SplitDiff a Info)
-openDiff source diff@(Free (Annotated (Info range _) _)) = case (source !!) <$> maybeLastIndex range of
-  Just '\n' -> Nothing
-  _ -> Just diff
+openDiff source diff@(Free (Annotated (Info range _) _)) = const diff <$> openRange source range
 openDiff source diff@(Pure term) = const diff <$> openTerm source term
 
 openLineBy :: (a -> Maybe a) -> [Line a] -> Maybe (Line a)

From c7a7a7987ed4165a46856287e06b5ba183ca2748 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 10:02:17 -0500
Subject: [PATCH 130/259] splitDiffByLines & splitAnnotatedByLines produce rows
 of split diffs.

---
 src/Split.hs | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index cc5fb42e9..02ef238ff 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -132,16 +132,16 @@ instance Monoid (Line a) where
 -- | A diff with only one side’s annotations.
 type SplitDiff leaf annotation = Free (Annotated leaf annotation) (Term leaf annotation)
 
-splitDiffByLines :: Diff a Info -> (Int, Int) -> (String, String) -> ([Row (Term a Info)], (Range, Range))
+splitDiffByLines :: Diff a Info -> (Int, Int) -> (String, String) -> ([Row (SplitDiff a Info)], (Range, Range))
 splitDiffByLines diff (prevLeft, prevRight) sources = case diff of
   Free (Annotated annotation syntax) -> (splitAnnotatedByLines sources (ranges annotation) (categories annotation) syntax, ranges annotation)
   Pure (Insert term) -> let (lines, range) = splitTermByLines term (snd sources) in
-    (Row EmptyLine <$> lines, (Range prevLeft prevLeft, range))
+    (Row EmptyLine . fmap Pure <$> lines, (Range prevLeft prevLeft, range))
   Pure (Delete term) -> let (lines, range) = splitTermByLines term (fst sources) in
-    (flip Row EmptyLine <$> lines, (range, Range prevRight prevRight))
+    (flip Row EmptyLine . fmap Pure <$> lines, (range, Range prevRight prevRight))
   Pure (Replace leftTerm rightTerm) -> let (leftLines, leftRange) = splitTermByLines leftTerm (fst sources)
                                            (rightLines, rightRange) = splitTermByLines rightTerm (snd sources) in
-                                           (zipWithDefaults Row EmptyLine EmptyLine leftLines rightLines, (leftRange, rightRange))
+                                           (zipWithDefaults Row EmptyLine EmptyLine (fmap Pure <$> leftLines) (fmap Pure <$> rightLines), (leftRange, rightRange))
   where categories (Info _ left, Info _ right) = (left, right)
         ranges (Info left _, Info right _) = (left, right)
 
@@ -197,15 +197,16 @@ termToLines (Info range categories :< syntax) source = (rows syntax, range)
       (adjoin $ lines ++ contextLines (Range previous $ start childRange) source ++ childLines, end childRange)
     elements = elementAndBreak (Span $ classify categories) =<< actualLines (substring range source)
 
-splitAnnotatedByLines :: (String, String) -> (Range, Range) -> (Set.Set Category, Set.Set Category) -> Syntax a (Diff a Info) -> [Row (Term a Info)]
+splitAnnotatedByLines :: (String, String) -> (Range, Range) -> (Set.Set Category, Set.Set Category) -> Syntax a (Diff a Info) -> [Row (SplitDiff a Info)]
 splitAnnotatedByLines sources ranges categories syntax = case syntax of
   Leaf a -> contextRows (Leaf a) ranges categories sources
   Indexed children -> adjoinChildRows Indexed children
   Fixed children -> adjoinChildRows Fixed children
   Keyed children -> adjoinChildRows Keyed children
   where contextRows constructor ranges categories sources = zipWithDefaults Row EmptyLine EmptyLine (contextLines constructor (fst ranges) (fst categories) (fst sources)) (contextLines constructor (snd ranges) (snd categories) (snd sources))
+        contextLines constructor range categories source = Line True . (:[]) . Free . (`Annotated` constructor) . (`Info` categories) <$> actualLineRanges range source
 
-        adjoin = reverse . foldl (adjoinRowsBy (openTerm $ fst sources) (openTerm $ snd sources)) []
+        adjoin = reverse . foldl (adjoinRowsBy (openDiff $ fst sources) (openDiff $ snd sources)) []
         adjoinChildRows constructor children = let (rows, previous) = foldl (childRows $ constructor mempty) ([], starts ranges) children in
           adjoin $ rows ++ contextRows (constructor mempty) (makeRanges previous (ends ranges)) categories sources
 

From 37860544acef5d1c1296a009cf997f61288c169f Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 10:09:06 -0500
Subject: [PATCH 131/259] Generalize `contextLines` to return `[Line a]`.

---
 src/Split.hs | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 02ef238ff..b1290d767 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -167,16 +167,16 @@ diffToRows (Pure (Replace a b)) _ before after = (replacedRows, (leftRange, righ
 -- | Takes a term and a source and returns a list of lines and their range within source.
 splitTermByLines :: Term a Info -> String -> ([Line (Term a Info)], Range)
 splitTermByLines (Info range categories :< syntax) source = flip (,) range $ case syntax of
-  Leaf a -> contextLines (Leaf a) range categories source
+  Leaf a -> contextLines (:< Leaf a) range categories source
   Indexed children -> adjoinChildLines Indexed children
   Fixed children -> adjoinChildLines Fixed children
   Keyed children -> adjoinChildLines Keyed children
   where adjoin = reverse . foldl (adjoinLinesBy $ openTerm source) []
         adjoinChildLines constructor children = let (lines, previous) = foldl (childLines $ constructor mempty) ([], start range) children in
-          adjoin $ lines ++ contextLines (constructor mempty) (Range previous $ end range) categories source
+          adjoin $ lines ++ contextLines (:< constructor mempty) (Range previous $ end range) categories source
 
         childLines constructor (lines, previous) child = let (childLines, childRange) = splitTermByLines child source in
-          (adjoin $ lines ++ contextLines constructor (Range previous $ start childRange) categories source ++ childLines, end childRange)
+          (adjoin $ lines ++ contextLines (:< constructor) (Range previous $ start childRange) categories source ++ childLines, end childRange)
 
 -- | Takes a term and a source and returns a list of lines and their range within source.
 termToLines :: Term a Info -> String -> ([Line HTML], Range)
@@ -241,8 +241,8 @@ annotatedToRows (Annotated (Info left leftCategories, Info right rightCategories
     sumRows (rows, previousIndices) child = let (childRows, childRanges) = diffToRows child previousIndices before after in
       (rows ++ contextRows (starts childRanges) previousIndices sources ++ childRows, ends childRanges)
 
-contextLines :: Syntax a (Term a Info) -> Range -> Set.Set Category -> String -> [Line (Term a Info)]
-contextLines constructor range categories source = Line True . (:[]) . (:< constructor) . (`Info` categories) <$> actualLineRanges range source
+contextLines :: (Info -> a) -> Range -> Set.Set Category -> String -> [Line a]
+contextLines constructor range categories source = Line True . (:[]) . constructor . (`Info` categories) <$> actualLineRanges range source
 
 contextRows :: (Int, Int) -> (Int, Int) -> (String, String) -> [Row HTML]
 contextRows childIndices previousIndices sources = zipWithMaybe rowFromMaybeRows leftElements rightElements

From c70eb44f9049717a692eb85ada07349d28089452 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 10:09:26 -0500
Subject: [PATCH 132/259] Use the global `contextLines` function.

---
 src/Split.hs | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index b1290d767..df827bbd5 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -203,8 +203,7 @@ splitAnnotatedByLines sources ranges categories syntax = case syntax of
   Indexed children -> adjoinChildRows Indexed children
   Fixed children -> adjoinChildRows Fixed children
   Keyed children -> adjoinChildRows Keyed children
-  where contextRows constructor ranges categories sources = zipWithDefaults Row EmptyLine EmptyLine (contextLines constructor (fst ranges) (fst categories) (fst sources)) (contextLines constructor (snd ranges) (snd categories) (snd sources))
-        contextLines constructor range categories source = Line True . (:[]) . Free . (`Annotated` constructor) . (`Info` categories) <$> actualLineRanges range source
+  where contextRows constructor ranges categories sources = zipWithDefaults Row EmptyLine EmptyLine (contextLines (Free . (`Annotated` constructor)) (fst ranges) (fst categories) (fst sources)) (contextLines (Free . (`Annotated` constructor)) (snd ranges) (snd categories) (snd sources))
 
         adjoin = reverse . foldl (adjoinRowsBy (openDiff $ fst sources) (openDiff $ snd sources)) []
         adjoinChildRows constructor children = let (rows, previous) = foldl (childRows $ constructor mempty) ([], starts ranges) children in

From 6703efceb61d7d8dcd40ae16179de7124d26b8ae Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 10:20:36 -0500
Subject: [PATCH 133/259] Stub in a RenderableSplitDiff type.

---
 src/Split.hs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/Split.hs b/src/Split.hs
index df827bbd5..435fb7b2d 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -132,6 +132,8 @@ instance Monoid (Line a) where
 -- | A diff with only one side’s annotations.
 type SplitDiff leaf annotation = Free (Annotated leaf annotation) (Term leaf annotation)
 
+newtype RenderableSplitDiff leaf annotation = RenderableSplitDiff (String, SplitDiff leaf annotation)
+
 splitDiffByLines :: Diff a Info -> (Int, Int) -> (String, String) -> ([Row (SplitDiff a Info)], (Range, Range))
 splitDiffByLines diff (prevLeft, prevRight) sources = case diff of
   Free (Annotated annotation syntax) -> (splitAnnotatedByLines sources (ranges annotation) (categories annotation) syntax, ranges annotation)

From a04f57303c767bde1e52ade97099ef78b8dff681 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 10:24:37 -0500
Subject: [PATCH 134/259] Reduce `RenderableSplitDiff` to `Renderable`.

---
 src/Split.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index 435fb7b2d..dca6a170b 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -132,7 +132,7 @@ instance Monoid (Line a) where
 -- | A diff with only one side’s annotations.
 type SplitDiff leaf annotation = Free (Annotated leaf annotation) (Term leaf annotation)
 
-newtype RenderableSplitDiff leaf annotation = RenderableSplitDiff (String, SplitDiff leaf annotation)
+newtype Renderable a = Renderable (String, a)
 
 splitDiffByLines :: Diff a Info -> (Int, Int) -> (String, String) -> ([Row (SplitDiff a Info)], (Range, Range))
 splitDiffByLines diff (prevLeft, prevRight) sources = case diff of

From 8d0db8ed06a47d1f4643274585936b9cd60ad52f Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 10:28:57 -0500
Subject: [PATCH 135/259] Define a ToMarkup instance over Renderable leaf
 terms.

---
 src/Split.hs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/Split.hs b/src/Split.hs
index dca6a170b..bc0d8b294 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -134,6 +134,10 @@ type SplitDiff leaf annotation = Free (Annotated leaf annotation) (Term leaf ann
 
 newtype Renderable a = Renderable (String, a)
 
+instance ToMarkup (Renderable (Term a Info)) where
+  toMarkup (Renderable (source, Info range categories :< syntax)) = case syntax of
+    Leaf _ -> classifyMarkup (maybeLast categories) . span . string $ substring range source
+
 splitDiffByLines :: Diff a Info -> (Int, Int) -> (String, String) -> ([Row (SplitDiff a Info)], (Range, Range))
 splitDiffByLines diff (prevLeft, prevRight) sources = case diff of
   Free (Annotated annotation syntax) -> (splitAnnotatedByLines sources (ranges annotation) (categories annotation) syntax, ranges annotation)

From b4ae80239afd2a9fb98904b956ac457bcab51d39 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 10:41:23 -0500
Subject: [PATCH 136/259] Classify the markup outside of the case expression.

---
 src/Split.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index bc0d8b294..b0e349e14 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -135,8 +135,8 @@ type SplitDiff leaf annotation = Free (Annotated leaf annotation) (Term leaf ann
 newtype Renderable a = Renderable (String, a)
 
 instance ToMarkup (Renderable (Term a Info)) where
-  toMarkup (Renderable (source, Info range categories :< syntax)) = case syntax of
-    Leaf _ -> classifyMarkup (maybeLast categories) . span . string $ substring range source
+  toMarkup (Renderable (source, Info range categories :< syntax)) = classifyMarkup (maybeLast categories) $ case syntax of
+    Leaf _ -> span . string $ substring range source
 
 splitDiffByLines :: Diff a Info -> (Int, Int) -> (String, String) -> ([Row (SplitDiff a Info)], (Range, Range))
 splitDiffByLines diff (prevLeft, prevRight) sources = case diff of

From a267cbdd7a78ab64125c3e98db1e07abe52d0830 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 10:52:22 -0500
Subject: [PATCH 137/259] Add a function to get the markup & separator for a
 given child term.

---
 src/Split.hs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/Split.hs b/src/Split.hs
index b0e349e14..3d730af70 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -137,6 +137,9 @@ newtype Renderable a = Renderable (String, a)
 instance ToMarkup (Renderable (Term a Info)) where
   toMarkup (Renderable (source, Info range categories :< syntax)) = classifyMarkup (maybeLast categories) $ case syntax of
     Leaf _ -> span . string $ substring range source
+    where markupForSeparatorAndChild :: ([Markup], Int) -> Term a Info -> ([Markup], Int)
+          markupForSeparatorAndChild (rows, previous) child = (rows ++ [ string (substring (Range previous $ start $ getRange child) source), toMarkup (Renderable (source, child)) ], end $ getRange child)
+          getRange (Info range _ :< _) = range
 
 splitDiffByLines :: Diff a Info -> (Int, Int) -> (String, String) -> ([Row (SplitDiff a Info)], (Range, Range))
 splitDiffByLines diff (prevLeft, prevRight) sources = case diff of

From 1197182f35b65312ff69d221e14d2e5627e6c4ca Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 10:52:36 -0500
Subject: [PATCH 138/259] Define toMarkup over Renderable indexed terms.

---
 src/Split.hs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/Split.hs b/src/Split.hs
index 3d730af70..74eb8a35b 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -137,6 +137,8 @@ newtype Renderable a = Renderable (String, a)
 instance ToMarkup (Renderable (Term a Info)) where
   toMarkup (Renderable (source, Info range categories :< syntax)) = classifyMarkup (maybeLast categories) $ case syntax of
     Leaf _ -> span . string $ substring range source
+    Indexed children -> ul . mconcat $ let (elements, previous) = foldl markupForSeparatorAndChild ([], start range) children in
+      elements ++ [ string $ substring (Range previous $ end range) source ]
     where markupForSeparatorAndChild :: ([Markup], Int) -> Term a Info -> ([Markup], Int)
           markupForSeparatorAndChild (rows, previous) child = (rows ++ [ string (substring (Range previous $ start $ getRange child) source), toMarkup (Renderable (source, child)) ], end $ getRange child)
           getRange (Info range _ :< _) = range

From a0ac63f8b7f818d8911f0dad254b7d21b7cc83f8 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 10:54:31 -0500
Subject: [PATCH 139/259] Extract the handling of the contents into a binding.

---
 src/Split.hs | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 74eb8a35b..f0d5010f5 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -137,10 +137,13 @@ newtype Renderable a = Renderable (String, a)
 instance ToMarkup (Renderable (Term a Info)) where
   toMarkup (Renderable (source, Info range categories :< syntax)) = classifyMarkup (maybeLast categories) $ case syntax of
     Leaf _ -> span . string $ substring range source
-    Indexed children -> ul . mconcat $ let (elements, previous) = foldl markupForSeparatorAndChild ([], start range) children in
-      elements ++ [ string $ substring (Range previous $ end range) source ]
+    Indexed children -> ul . mconcat $ contentElements children
     where markupForSeparatorAndChild :: ([Markup], Int) -> Term a Info -> ([Markup], Int)
           markupForSeparatorAndChild (rows, previous) child = (rows ++ [ string (substring (Range previous $ start $ getRange child) source), toMarkup (Renderable (source, child)) ], end $ getRange child)
+
+          contentElements children = let (elements, previous) = foldl markupForSeparatorAndChild ([], start range) children in
+            elements ++ [ string $ substring (Range previous $ end range) source ]
+
           getRange (Info range _ :< _) = range
 
 splitDiffByLines :: Diff a Info -> (Int, Int) -> (String, String) -> ([Row (SplitDiff a Info)], (Range, Range))

From 1bed6a771032254fdefced91dddfe713435f1f2f Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 10:54:54 -0500
Subject: [PATCH 140/259] Define toMarkup over Renderable fixed terms.

---
 src/Split.hs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/Split.hs b/src/Split.hs
index f0d5010f5..ba23c284d 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -138,6 +138,7 @@ instance ToMarkup (Renderable (Term a Info)) where
   toMarkup (Renderable (source, Info range categories :< syntax)) = classifyMarkup (maybeLast categories) $ case syntax of
     Leaf _ -> span . string $ substring range source
     Indexed children -> ul . mconcat $ contentElements children
+    Fixed children -> ul . mconcat $ contentElements children
     where markupForSeparatorAndChild :: ([Markup], Int) -> Term a Info -> ([Markup], Int)
           markupForSeparatorAndChild (rows, previous) child = (rows ++ [ string (substring (Range previous $ start $ getRange child) source), toMarkup (Renderable (source, child)) ], end $ getRange child)
 

From 25a524ce22a0f5454c8b48d508ea27ee493b4b16 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 10:55:28 -0500
Subject: [PATCH 141/259] Define toMarkup over Renderable keyed terms.

---
 src/Split.hs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/Split.hs b/src/Split.hs
index ba23c284d..f5e886b10 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -139,6 +139,7 @@ instance ToMarkup (Renderable (Term a Info)) where
     Leaf _ -> span . string $ substring range source
     Indexed children -> ul . mconcat $ contentElements children
     Fixed children -> ul . mconcat $ contentElements children
+    Keyed children -> dl . mconcat $ contentElements children
     where markupForSeparatorAndChild :: ([Markup], Int) -> Term a Info -> ([Markup], Int)
           markupForSeparatorAndChild (rows, previous) child = (rows ++ [ string (substring (Range previous $ start $ getRange child) source), toMarkup (Renderable (source, child)) ], end $ getRange child)
 

From eab354c5f9a57347f6fd7f1940a2eb3ab5bacb06 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 10:56:23 -0500
Subject: [PATCH 142/259] Define a ToMarkup instance over Renderable pure
 SplitDiffs.

---
 src/Split.hs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/Split.hs b/src/Split.hs
index f5e886b10..a904b1d20 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -148,6 +148,9 @@ instance ToMarkup (Renderable (Term a Info)) where
 
           getRange (Info range _ :< _) = range
 
+instance ToMarkup (Renderable (SplitDiff a Info)) where
+  toMarkup (Renderable (source, Pure term)) = toMarkup (Renderable (source, term))
+
 splitDiffByLines :: Diff a Info -> (Int, Int) -> (String, String) -> ([Row (SplitDiff a Info)], (Range, Range))
 splitDiffByLines diff (prevLeft, prevRight) sources = case diff of
   Free (Annotated annotation syntax) -> (splitAnnotatedByLines sources (ranges annotation) (categories annotation) syntax, ranges annotation)

From 5e361e75488a50c1a04ca21eb322c9b4881fc145 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 10:58:21 -0500
Subject: [PATCH 143/259] Stub in a definition of toMarkup over Renderable free
 SplitDiffs.

---
 src/Split.hs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/Split.hs b/src/Split.hs
index a904b1d20..5d593eb31 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -150,6 +150,8 @@ instance ToMarkup (Renderable (Term a Info)) where
 
 instance ToMarkup (Renderable (SplitDiff a Info)) where
   toMarkup (Renderable (source, Pure term)) = toMarkup (Renderable (source, term))
+  toMarkup (Renderable (source, Free (Annotated (Info range categories) syntax))) = classifyMarkup (maybeLast categories) $ case syntax of
+    _ -> br
 
 splitDiffByLines :: Diff a Info -> (Int, Int) -> (String, String) -> ([Row (SplitDiff a Info)], (Range, Range))
 splitDiffByLines diff (prevLeft, prevRight) sources = case diff of

From 0c7a59f9c9996b23ac5d12cc2839d329afe021bd Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 11:26:29 -0500
Subject: [PATCH 144/259] Define toMarkup over Renderable ranged syntax.

---
 src/Split.hs | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 5d593eb31..fb8e7de53 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -134,19 +134,18 @@ type SplitDiff leaf annotation = Free (Annotated leaf annotation) (Term leaf ann
 
 newtype Renderable a = Renderable (String, a)
 
-instance ToMarkup (Renderable (Term a Info)) where
-  toMarkup (Renderable (source, Info range categories :< syntax)) = classifyMarkup (maybeLast categories) $ case syntax of
+instance ToMarkup f => ToMarkup (Renderable (Info, Syntax a (f, Range))) where
+  toMarkup (Renderable (source, (Info range categories, syntax))) = classifyMarkup (maybeLast categories) $ case syntax of
     Leaf _ -> span . string $ substring range source
     Indexed children -> ul . mconcat $ contentElements children
     Fixed children -> ul . mconcat $ contentElements children
     Keyed children -> dl . mconcat $ contentElements children
-    where markupForSeparatorAndChild :: ([Markup], Int) -> Term a Info -> ([Markup], Int)
-          markupForSeparatorAndChild (rows, previous) child = (rows ++ [ string (substring (Range previous $ start $ getRange child) source), toMarkup (Renderable (source, child)) ], end $ getRange child)
+    where markupForSeparatorAndChild :: ToMarkup f => ([Markup], Int) -> (f, Range) -> ([Markup], Int)
+          markupForSeparatorAndChild (rows, previous) child = (rows ++ [ string (substring (Range previous $ start $ snd child) source), toMarkup $ fst child ], end $ snd child)
 
           contentElements children = let (elements, previous) = foldl markupForSeparatorAndChild ([], start range) children in
             elements ++ [ string $ substring (Range previous $ end range) source ]
 
-          getRange (Info range _ :< _) = range
 
 instance ToMarkup (Renderable (SplitDiff a Info)) where
   toMarkup (Renderable (source, Pure term)) = toMarkup (Renderable (source, term))

From 0af18aa16d53c0b829d61f161c83aef5885d60e6 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 11:28:20 -0500
Subject: [PATCH 145/259] Define toMarkup for Renderable terms via the
 Renderable syntax instance.

---
 src/Split.hs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/Split.hs b/src/Split.hs
index fb8e7de53..d2958be61 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -146,6 +146,8 @@ instance ToMarkup f => ToMarkup (Renderable (Info, Syntax a (f, Range))) where
           contentElements children = let (elements, previous) = foldl markupForSeparatorAndChild ([], start range) children in
             elements ++ [ string $ substring (Range previous $ end range) source ]
 
+instance ToMarkup (Renderable (Term a Info)) where
+  toMarkup (Renderable (source, term)) = fst $ cata (\ info@(Info range _) syntax -> (toMarkup $ Renderable (source, (info, syntax)), range)) term
 
 instance ToMarkup (Renderable (SplitDiff a Info)) where
   toMarkup (Renderable (source, Pure term)) = toMarkup (Renderable (source, term))

From ab951a9c6b544e72aaabae7c8f6ae49b1aad0946 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 11:38:19 -0500
Subject: [PATCH 146/259] Define toMarkup over Renderable SplitDiffs by
 iteration.

---
 src/Split.hs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index d2958be61..cd14569f8 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -150,9 +150,9 @@ instance ToMarkup (Renderable (Term a Info)) where
   toMarkup (Renderable (source, term)) = fst $ cata (\ info@(Info range _) syntax -> (toMarkup $ Renderable (source, (info, syntax)), range)) term
 
 instance ToMarkup (Renderable (SplitDiff a Info)) where
-  toMarkup (Renderable (source, Pure term)) = toMarkup (Renderable (source, term))
-  toMarkup (Renderable (source, Free (Annotated (Info range categories) syntax))) = classifyMarkup (maybeLast categories) $ case syntax of
-    _ -> br
+  toMarkup (Renderable (source, diff)) = fst $ iter (\ (Annotated info@(Info range _) syntax) -> (toMarkup $ Renderable (source, (info, syntax)), range)) $ toMarkupAndRange <$> diff
+    where toMarkupAndRange :: Term a Info -> (Markup, Range)
+          toMarkupAndRange term@(Info range _ :< _) = (toMarkup $ Renderable (source, term), range)
 
 splitDiffByLines :: Diff a Info -> (Int, Int) -> (String, String) -> ([Row (SplitDiff a Info)], (Range, Range))
 splitDiffByLines diff (prevLeft, prevRight) sources = case diff of

From d0460f8792d680b41158b79558a1a5f6e63fe823 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 11:41:14 -0500
Subject: [PATCH 147/259] Wrap patches in a div.

---
 src/Split.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index cd14569f8..39e413c55 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -152,7 +152,7 @@ instance ToMarkup (Renderable (Term a Info)) where
 instance ToMarkup (Renderable (SplitDiff a Info)) where
   toMarkup (Renderable (source, diff)) = fst $ iter (\ (Annotated info@(Info range _) syntax) -> (toMarkup $ Renderable (source, (info, syntax)), range)) $ toMarkupAndRange <$> diff
     where toMarkupAndRange :: Term a Info -> (Markup, Range)
-          toMarkupAndRange term@(Info range _ :< _) = (toMarkup $ Renderable (source, term), range)
+          toMarkupAndRange term@(Info range _ :< _) = ((div ! A.class_ (stringValue "patch")) . toMarkup $ Renderable (source, term), range)
 
 splitDiffByLines :: Diff a Info -> (Int, Int) -> (String, String) -> ([Row (SplitDiff a Info)], (Range, Range))
 splitDiffByLines diff (prevLeft, prevRight) sources = case diff of

From a72e6b868fd48c6e2f171a18e38fcc03fa48be43 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 12:14:26 -0500
Subject: [PATCH 148/259] Split into rows.

---
 src/Split.hs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/Split.hs b/src/Split.hs
index 39e413c55..007ae69e4 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -61,6 +61,7 @@ split diff before after = return . renderHtml
         . mconcat $ toMarkup <$> reverse numbered
   where
     rows = fst $ diffToRows diff (0, 0) before after
+    rows' = fst $ splitDiffByLines diff (0, 0) (before, after)
     numbered = foldl numberRows [] rows
     maxNumber = case numbered of
       [] -> 0

From b76be23b6ee7b10be1502853bf2543486eda3376 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 12:22:00 -0500
Subject: [PATCH 149/259] Map rows into renderables.

---
 src/Split.hs | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index 007ae69e4..0e51ea9b0 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -61,7 +61,8 @@ split diff before after = return . renderHtml
         . mconcat $ toMarkup <$> reverse numbered
   where
     rows = fst $ diffToRows diff (0, 0) before after
-    rows' = fst $ splitDiffByLines diff (0, 0) (before, after)
+    rows' = toRenderable <$> fst (splitDiffByLines diff (0, 0) (before, after))
+    toRenderable (Row a b) = Row (Renderable . (,) before <$> a) (Renderable . (,) after <$> b)
     numbered = foldl numberRows [] rows
     maxNumber = case numbered of
       [] -> 0

From fc053ffa13da3830d6d10f84ecab5cbf1476a819 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 12:26:43 -0500
Subject: [PATCH 150/259] Replace the old row rendering with the new row
 rendering.

---
 src/Split.hs | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 0e51ea9b0..103adfd1a 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -60,8 +60,7 @@ split diff before after = return . renderHtml
         ((colgroup $ (col ! A.width (stringValue . show $ columnWidth)) <> col <> (col ! A.width (stringValue . show $ columnWidth)) <> col) <>)
         . mconcat $ toMarkup <$> reverse numbered
   where
-    rows = fst $ diffToRows diff (0, 0) before after
-    rows' = toRenderable <$> fst (splitDiffByLines diff (0, 0) (before, after))
+    rows = toRenderable <$> fst (splitDiffByLines diff (0, 0) (before, after))
     toRenderable (Row a b) = Row (Renderable . (,) before <$> a) (Renderable . (,) after <$> b)
     numbered = foldl numberRows [] rows
     maxNumber = case numbered of

From 3b3a62a77725bcd68fa0cf79c245c844310b1c53 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 12:39:54 -0500
Subject: [PATCH 151/259] Test that single-line leaves are split correctly.

---
 test/SplitSpec.hs | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 95dcfea02..9cf2e2afa 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -30,6 +30,13 @@ instance Arbitrary a => Arbitrary (Line a) where
 
 spec :: Spec
 spec = do
+  describe "splitAnnotatedByLines" $ do
+    it "outputs one row for single-line unchanged leaves" $
+      let sources = ("a", "a")
+          ranges = (Range 0 1, Range 0 1)
+          categories = (mempty, mempty) in
+          splitAnnotatedByLines sources ranges categories (Leaf "b") `shouldBe` [ Row (Line False [ Free $ Annotated (Info (fst ranges) (fst categories)) $ Leaf "b" ]) (Line False [ Free $ Annotated (Info (snd ranges) (snd categories)) $ Leaf "b" ]) ]
+
   describe "annotatedToRows" $ do
     it "outputs one row for single-line unchanged leaves" $
       annotatedToRows (unchanged "a" "leaf" (Leaf "")) "a" "a" `shouldBe` [ Row (Line False [ span "a" ]) (Line False [ span "a" ]) ]

From fbe899be217f34711e92fb310e6b59eb58636559 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 12:47:12 -0500
Subject: [PATCH 152/259] Remove the changed flag from `Line`.

---
 src/Split.hs      | 48 +++++++++++++-------------
 test/SplitSpec.hs | 86 +++++++++++++++++++++++------------------------
 2 files changed, 67 insertions(+), 67 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 103adfd1a..5e5bf888a 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -75,12 +75,12 @@ split diff before after = return . renderHtml
 
     numberRows :: [(Int, Line a, Int, Line a)] -> Row a -> [(Int, Line a, Int, Line a)]
     numberRows [] (Row EmptyLine EmptyLine) = []
-    numberRows [] (Row left@(Line _ _) EmptyLine) = [(1, left, 0, EmptyLine)]
-    numberRows [] (Row EmptyLine right@(Line _ _)) = [(0, EmptyLine, 1, right)]
+    numberRows [] (Row left@(Line _) EmptyLine) = [(1, left, 0, EmptyLine)]
+    numberRows [] (Row EmptyLine right@(Line _)) = [(0, EmptyLine, 1, right)]
     numberRows [] (Row left right) = [(1, left, 1, right)]
     numberRows rows@((leftCount, _, rightCount, _):_) (Row EmptyLine EmptyLine) = (leftCount, EmptyLine, rightCount, EmptyLine):rows
-    numberRows rows@((leftCount, _, rightCount, _):_) (Row left@(Line _ _) EmptyLine) = (leftCount + 1, left, rightCount, EmptyLine):rows
-    numberRows rows@((leftCount, _, rightCount, _):_) (Row EmptyLine right@(Line _ _)) = (leftCount, EmptyLine, rightCount + 1, right):rows
+    numberRows rows@((leftCount, _, rightCount, _):_) (Row left@(Line _) EmptyLine) = (leftCount + 1, left, rightCount, EmptyLine):rows
+    numberRows rows@((leftCount, _, rightCount, _):_) (Row EmptyLine right@(Line _)) = (leftCount, EmptyLine, rightCount + 1, right):rows
     numberRows rows@((leftCount, _, rightCount, _):_) (Row left right) = (leftCount + 1, left, rightCount + 1, right):rows
 
 
@@ -95,40 +95,40 @@ instance ToMarkup a => ToMarkup (Int, Line a, Int, Line a) where
 
 instance ToMarkup a => ToMarkup (Int, Line a) where
   toMarkup (_, line@EmptyLine) = numberTd "" <> toMarkup line <> string "\n"
-  toMarkup (num, line@(Line True _)) = td (string $ show num) ! A.class_ (stringValue "blob-num blob-num-replacement") <> toMarkup line <> string "\n"
-  toMarkup (num, line@(Line _ _)) = numberTd (show num) <> toMarkup line <> string "\n"
+  -- toMarkup (num, line@(Line _)) = td (string $ show num) ! A.class_ (stringValue "blob-num blob-num-replacement") <> toMarkup line <> string "\n"
+  toMarkup (num, line@(Line _)) = numberTd (show num) <> toMarkup line <> string "\n"
 
 numberTd :: String -> Html
 numberTd "" = td mempty ! A.class_ (stringValue "blob-num blob-num-empty empty-cell")
 numberTd s = td (string s) ! A.class_ (stringValue "blob-num")
 
-codeTd :: Bool -> Maybe Html -> Html
-codeTd _ Nothing = td mempty ! A.class_ (stringValue "blob-code blob-code-empty empty-cell")
-codeTd True (Just el) = td el ! A.class_ (stringValue "blob-code blob-code-replacement")
-codeTd _ (Just el) = td el ! A.class_ (stringValue "blob-code")
+codeTd :: Maybe Html -> Html
+codeTd Nothing = td mempty ! A.class_ (stringValue "blob-code blob-code-empty empty-cell")
+-- codeTd True (Just el) = td el ! A.class_ (stringValue "blob-code blob-code-replacement")
+codeTd (Just el) = td el ! A.class_ (stringValue "blob-code")
 
 instance ToMarkup a => ToMarkup (Line a) where
-  toMarkup EmptyLine = codeTd False Nothing
-  toMarkup (Line changed html) = codeTd changed . Just . mconcat $ toMarkup <$> html
+  toMarkup EmptyLine = codeTd Nothing
+  toMarkup (Line html) = codeTd . Just . mconcat $ toMarkup <$> html
 
 data Line a =
-  Line Bool [a]
+  Line [a]
   | EmptyLine
   deriving (Eq, Functor)
 
 unLine :: Line a -> [a]
 unLine EmptyLine = []
-unLine (Line _ elements) = elements
+unLine (Line elements) = elements
 
 instance Show a => Show (Line a) where
-  show (Line change elements) = show change ++ " [" ++ intercalate ", " (show <$> elements) ++ "]"
+  show (Line elements) = "[" ++ intercalate ", " (show <$> elements) ++ "]"
   show EmptyLine = "EmptyLine"
 
 instance Monoid (Line a) where
   mempty = EmptyLine
   mappend EmptyLine line = line
   mappend line EmptyLine = line
-  mappend (Line c1 xs) (Line c2 ys) = Line (c1 || c2) (xs <> ys)
+  mappend (Line xs) (Line ys) = Line (xs <> ys)
 
 -- | A diff with only one side’s annotations.
 type SplitDiff leaf annotation = Free (Annotated leaf annotation) (Term leaf annotation)
@@ -173,12 +173,12 @@ diffToRows (Free annotated@(Annotated (Info left _, Info right _) _)) _ before a
 diffToRows (Pure (Insert term)) (previousIndex, _) _ after = (rowWithInsertedLine <$> afterLines, (Range previousIndex previousIndex, range))
   where
     (afterLines, range) = termToLines term after
-    rowWithInsertedLine (Line _ elements) = Row EmptyLine $ Line True [ Div (Just "insert") elements ]
+    rowWithInsertedLine (Line elements) = Row EmptyLine $ Line [ Div (Just "insert") elements ]
     rowWithInsertedLine line = Row line line
 diffToRows (Pure (Delete term)) (_, previousIndex) before _ = (rowWithDeletedLine <$> lines, (range, Range previousIndex previousIndex))
   where
     (lines, range) = termToLines term before
-    rowWithDeletedLine (Line _ elements) = Row (Line True [ Div (Just "delete") elements ]) EmptyLine
+    rowWithDeletedLine (Line elements) = Row (Line [ Div (Just "delete") elements ]) EmptyLine
     rowWithDeletedLine line = Row line line
 diffToRows (Pure (Replace a b)) _ before after = (replacedRows, (leftRange, rightRange))
   where
@@ -205,15 +205,15 @@ splitTermByLines (Info range categories :< syntax) source = flip (,) range $ cas
 termToLines :: Term a Info -> String -> ([Line HTML], Range)
 termToLines (Info range categories :< syntax) source = (rows syntax, range)
   where
-    rows (Leaf _) = adjoin $ Line True . (:[]) <$> elements
+    rows (Leaf _) = adjoin $ Line . (:[]) <$> elements
     rows (Indexed i) = rewrapLineContentsIn (Ul $ classify categories) <$> childLines i
     rows (Fixed f) = rewrapLineContentsIn (Ul $ classify categories) <$> childLines f
     rows (Keyed k) = rewrapLineContentsIn (Dl $ classify categories) <$> childLines k
 
     adjoin = reverse . foldl (adjoinLinesBy openElement) []
-    rewrapLineContentsIn f (Line _ elements) = Line True [ f elements ]
+    rewrapLineContentsIn f (Line elements) = Line [ f elements ]
     rewrapLineContentsIn _ EmptyLine = EmptyLine
-    contextLines r s = Line True . (:[]) <$> textElements r s
+    contextLines r s = Line . (:[]) <$> textElements r s
     childLines i = let (lines, previous) = foldl sumLines ([], start range) i in
       adjoin $ lines ++ contextLines (Range previous (end range)) source
     sumLines (lines, previous) child = let (childLines, childRange) = termToLines child source in
@@ -252,7 +252,7 @@ annotatedToRows (Annotated (Info left leftCategories, Info right rightCategories
     rightElements = elementAndBreak (Span $ classify rightCategories) =<< actualLines (substring right after)
 
     wrap _ EmptyLine = EmptyLine
-    wrap f (Line c elements) = Line c [ f elements ]
+    wrap f (Line elements) = Line [ f elements ]
     rewrapRowContentsIn f (Row left right) = Row (wrap (f $ classify leftCategories) left) (wrap (f $ classify rightCategories) right)
     ranges = (left, right)
     sources = (before, after)
@@ -264,7 +264,7 @@ annotatedToRows (Annotated (Info left leftCategories, Info right rightCategories
       (rows ++ contextRows (starts childRanges) previousIndices sources ++ childRows, ends childRanges)
 
 contextLines :: (Info -> a) -> Range -> Set.Set Category -> String -> [Line a]
-contextLines constructor range categories source = Line True . (:[]) . constructor . (`Info` categories) <$> actualLineRanges range source
+contextLines constructor range categories source = Line . (:[]) . constructor . (`Info` categories) <$> actualLineRanges range source
 
 contextRows :: (Int, Int) -> (Int, Int) -> (String, String) -> [Row HTML]
 contextRows childIndices previousIndices sources = zipWithMaybe rowFromMaybeRows leftElements rightElements
@@ -283,7 +283,7 @@ textElements range source = elementAndBreak Text =<< actualLines s
   where s = substring range source
 
 rowFromMaybeRows :: Maybe a -> Maybe a -> Row a
-rowFromMaybeRows a b = Row (maybe EmptyLine (Line False . (:[])) a) (maybe EmptyLine (Line False . (:[])) b)
+rowFromMaybeRows a b = Row (maybe EmptyLine (Line . (:[])) a) (maybe EmptyLine (Line . (:[])) b)
 
 maybeLast :: Foldable f => f a -> Maybe a
 maybeLast = foldl (flip $ const . Just) Nothing
diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 9cf2e2afa..7ee809fe6 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -25,7 +25,7 @@ instance Arbitrary HTML where
 
 instance Arbitrary a => Arbitrary (Line a) where
   arbitrary = oneof [
-    Line <$> arbitrary <*> arbitrary,
+    Line <$> arbitrary,
     const EmptyLine <$> (arbitrary :: Gen ()) ]
 
 spec :: Spec
@@ -35,26 +35,26 @@ spec = do
       let sources = ("a", "a")
           ranges = (Range 0 1, Range 0 1)
           categories = (mempty, mempty) in
-          splitAnnotatedByLines sources ranges categories (Leaf "b") `shouldBe` [ Row (Line False [ Free $ Annotated (Info (fst ranges) (fst categories)) $ Leaf "b" ]) (Line False [ Free $ Annotated (Info (snd ranges) (snd categories)) $ Leaf "b" ]) ]
+          splitAnnotatedByLines sources ranges categories (Leaf "b") `shouldBe` [ Row (Line [ Free $ Annotated (Info (fst ranges) (fst categories)) $ Leaf "b" ]) (Line [ Free $ Annotated (Info (snd ranges) (snd categories)) $ Leaf "b" ]) ]
 
   describe "annotatedToRows" $ do
     it "outputs one row for single-line unchanged leaves" $
-      annotatedToRows (unchanged "a" "leaf" (Leaf "")) "a" "a" `shouldBe` [ Row (Line False [ span "a" ]) (Line False [ span "a" ]) ]
+      annotatedToRows (unchanged "a" "leaf" (Leaf "")) "a" "a" `shouldBe` [ Row (Line [ span "a" ]) (Line [ span "a" ]) ]
 
     it "outputs one row for single-line empty unchanged indexed nodes" $
-      annotatedToRows (unchanged "[]" "branch" (Indexed [])) "[]" "[]" `shouldBe` [ Row (Line False [ Ul (Just "category-branch") [ Text "[]" ] ]) (Line False [ Ul (Just "category-branch") [ Text "[]" ] ]) ]
+      annotatedToRows (unchanged "[]" "branch" (Indexed [])) "[]" "[]" `shouldBe` [ Row (Line [ Ul (Just "category-branch") [ Text "[]" ] ]) (Line [ Ul (Just "category-branch") [ Text "[]" ] ]) ]
 
     it "outputs one row for single-line non-empty unchanged indexed nodes" $
       annotatedToRows (unchanged "[ a, b ]" "branch" (Indexed [
         Free . offsetAnnotated 2 2 $ unchanged "a" "leaf" (Leaf ""),
         Free . offsetAnnotated 5 5 $ unchanged "b" "leaf" (Leaf "")
-      ])) "[ a, b ]" "[ a, b ]" `shouldBe` [ Row (Line False [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ", ", span "b", Text " ]" ] ]) (Line False [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ", ", span "b", Text " ]" ] ]) ]
+      ])) "[ a, b ]" "[ a, b ]" `shouldBe` [ Row (Line [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ", ", span "b", Text " ]" ] ]) (Line [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ", ", span "b", Text " ]" ] ]) ]
 
     it "outputs one row for single-line non-empty formatted indexed nodes" $
       annotatedToRows (formatted "[ a, b ]" "[ a,  b ]" "branch" (Indexed [
         Free . offsetAnnotated 2 2 $ unchanged "a" "leaf" (Leaf ""),
         Free . offsetAnnotated 5 6 $ unchanged "b" "leaf" (Leaf "")
-      ])) "[ a, b ]" "[ a,  b ]" `shouldBe` [ Row (Line False [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ", ", span "b", Text " ]" ] ]) (Line False [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ",  ", span "b", Text " ]" ] ]) ]
+      ])) "[ a, b ]" "[ a,  b ]" `shouldBe` [ Row (Line [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ", ", span "b", Text " ]" ] ]) (Line [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ",  ", span "b", Text " ]" ] ]) ]
 
     it "outputs two rows for two-line non-empty unchanged indexed nodes" $
       annotatedToRows (unchanged "[ a,\nb ]" "branch" (Indexed [
@@ -62,10 +62,10 @@ spec = do
         Free . offsetAnnotated 5 5 $ unchanged "b" "leaf" (Leaf "")
       ])) "[ a,\nb ]" "[ a,\nb ]" `shouldBe`
       [
-          Row (Line False [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ",", Break ] ])
-              (Line False [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ",", Break] ]),
-          Row (Line False [ Ul (Just "category-branch") [ span "b", Text " ]" ] ])
-              (Line False [ Ul (Just "category-branch") [ span "b", Text " ]" ] ])
+          Row (Line [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ",", Break ] ])
+              (Line [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ",", Break] ]),
+          Row (Line [ Ul (Just "category-branch") [ span "b", Text " ]" ] ])
+              (Line [ Ul (Just "category-branch") [ span "b", Text " ]" ] ])
       ]
 
     it "outputs two rows for two-line non-empty formatted indexed nodes" $
@@ -74,12 +74,12 @@ spec = do
         Free . offsetAnnotated 5 5 $ unchanged "b" "leaf" (Leaf "")
       ])) "[ a,\nb ]" "[\na,\nb ]" `shouldBe`
       [
-          Row (Line False [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ",", Break ] ])
-              (Line False [ Ul (Just "category-branch") [ Text "[", Break ] ]),
+          Row (Line [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ",", Break ] ])
+              (Line [ Ul (Just "category-branch") [ Text "[", Break ] ]),
           Row EmptyLine
-              (Line False [ Ul (Just "category-branch") [ span "a", Text ",", Break ] ]),
-          Row (Line False [ Ul (Just "category-branch") [ span "b", Text " ]" ] ])
-              (Line False [ Ul (Just "category-branch") [ span "b", Text " ]" ] ])
+              (Line [ Ul (Just "category-branch") [ span "a", Text ",", Break ] ]),
+          Row (Line [ Ul (Just "category-branch") [ span "b", Text " ]" ] ])
+              (Line [ Ul (Just "category-branch") [ span "b", Text " ]" ] ])
       ]
 
     it "" $
@@ -89,13 +89,13 @@ spec = do
           Free . offsetAnnotated 6 3 $ unchanged "b" "leaf" (Leaf "")
         ])) sourceA sourceB `shouldBe`
         [
-            Row (Line False [ Ul (Just "category-branch") [ Text "[", Break ] ])
-                (Line False [ Ul (Just "category-branch") [ Text "[", span "a", Text ",", span "b", Text "]" ] ]),
-            Row (Line False [ Ul (Just "category-branch") [ span "a", Break ] ])
+            Row (Line [ Ul (Just "category-branch") [ Text "[", Break ] ])
+                (Line [ Ul (Just "category-branch") [ Text "[", span "a", Text ",", span "b", Text "]" ] ]),
+            Row (Line [ Ul (Just "category-branch") [ span "a", Break ] ])
                 EmptyLine,
-            Row (Line False [ Ul (Just "category-branch") [ Text ",", Break ] ])
+            Row (Line [ Ul (Just "category-branch") [ Text ",", Break ] ])
                 EmptyLine,
-            Row (Line False [ Ul (Just "category-branch") [ span "b", Text "]" ] ])
+            Row (Line [ Ul (Just "category-branch") [ span "b", Text "]" ] ])
                 EmptyLine
         ]
 
@@ -106,9 +106,9 @@ spec = do
           Free . offsetAnnotated 6 0 $ unchanged "a" "leaf" (Leaf "")
         ])) sourceA sourceB `shouldBe`
         [
-          Row (Line True [ Ul (Just "category-branch") [ Div (Just "delete") [ span "/*", Break ] ] ]) EmptyLine,
-          Row (Line True [ Ul (Just "category-branch") [ Div (Just "delete") [ span "*/" ], Break ] ]) EmptyLine,
-          Row (Line False [ Ul (Just "category-branch") [ span "a" ] ]) (Line False [ Ul (Just "category-branch") [ span "a" ] ])
+          Row (Line [ Ul (Just "category-branch") [ Div (Just "delete") [ span "/*", Break ] ] ]) EmptyLine,
+          Row (Line [ Ul (Just "category-branch") [ Div (Just "delete") [ span "*/" ], Break ] ]) EmptyLine,
+          Row (Line [ Ul (Just "category-branch") [ span "a" ] ]) (Line [ Ul (Just "category-branch") [ span "a" ] ])
         ]
 
     describe "unicode" $
@@ -117,7 +117,7 @@ spec = do
             syntax = Leaf . Pure $ Replace (info sourceA "leaf" :< Leaf "") (info sourceB "leaf" :< Leaf "")
         in
             annotatedToRows (formatted sourceA sourceB "leaf" syntax) sourceA sourceB `shouldBe`
-            [ Row (Line False [ span "t\776" ]) (Line False [ span "\7831"]) ]
+            [ Row (Line [ span "t\776" ]) (Line [ span "\7831"]) ]
 
 
   describe "adjoinRowsBy" $ do
@@ -126,8 +126,8 @@ spec = do
 
     prop "appends onto open rows" $
       forAll ((arbitrary `suchThat` isOpen) >>= \ a -> (,) a <$> (arbitrary `suchThat` isOpen)) $
-        \ (a@(Row (Line ac1 as1) (Line bc1 bs1)), b@(Row (Line ac2 as2) (Line bc2 bs2))) ->
-          adjoinRowsBy openElement openElement [ a ] b `shouldBe` [ Row (Line (ac1 || ac2) $ as1 ++ as2) (Line (bc1 || bc2) $ bs1 ++ bs2) ]
+        \ (a@(Row (Line a1) (Line b1)), b@(Row (Line a2) (Line b2))) ->
+          adjoinRowsBy openElement openElement [ a ] b `shouldBe` [ Row (Line $ a1 ++ a2) (Line $ b1 ++ b2) ]
 
     prop "does not append onto closed rows" $
       forAll ((arbitrary `suchThat` isClosed) >>= \ a -> (,) a <$> (arbitrary `suchThat` isClosed)) $
@@ -146,8 +146,8 @@ spec = do
       termToLines (Info (Range 0 5) (Set.singleton "leaf") :< Leaf "") "/*\n*/"
       `shouldBe`
       ([
-        Line True [ span "/*", Break ],
-        Line True [ span "*/" ]
+        Line [ span "/*", Break ],
+        Line [ span "*/" ]
       ], Range 0 5)
 
   describe "splitTermByLines" $ do
@@ -155,32 +155,32 @@ spec = do
       splitTermByLines (Info (Range 0 5) mempty :< Leaf "") "/*\n*/"
       `shouldBe`
       ([
-        Line True [ Info (Range 0 3) mempty :< Leaf "" ],
-        Line True [ Info (Range 3 5) mempty :< Leaf "" ]
+        Line [ Info (Range 0 3) mempty :< Leaf "" ],
+        Line [ Info (Range 3 5) mempty :< Leaf "" ]
       ], Range 0 5)
 
   describe "openLineBy" $ do
     it "produces the earliest non-empty line in a list, if open" $
       openLineBy openElement [
-        Line True [ Div (Just "delete") [ span "*/" ] ],
-        Line True [ Div (Just "delete") [ span " * Debugging", Break ] ],
-        Line True [ Div (Just "delete") [ span "/*", Break ] ]
-      ] `shouldBe` (Just $ Line True [ Div (Just "delete") [ span "*/" ] ])
+        Line [ Div (Just "delete") [ span "*/" ] ],
+        Line [ Div (Just "delete") [ span " * Debugging", Break ] ],
+        Line [ Div (Just "delete") [ span "/*", Break ] ]
+      ] `shouldBe` (Just $ Line [ Div (Just "delete") [ span "*/" ] ])
 
     it "produces the earliest non-empty line in a list, if open" $
       openLineBy (openTerm "\n ") [
-        Line True [ Info (Range 1 2) mempty :< Leaf "" ],
-        Line True [ Info (Range 0 1) mempty :< Leaf "" ]
-      ] `shouldBe` (Just $ Line True [ Info (Range 1 2) mempty :< Leaf "" ])
+        Line [ Info (Range 1 2) mempty :< Leaf "" ],
+        Line [ Info (Range 0 1) mempty :< Leaf "" ]
+      ] `shouldBe` (Just $ Line [ Info (Range 1 2) mempty :< Leaf "" ])
 
     it "returns Nothing if the earliest non-empty line is closed" $
       openLineBy openElement [
-        Line True [ Div (Just "delete") [ span " * Debugging", Break ] ]
+        Line [ Div (Just "delete") [ span " * Debugging", Break ] ]
       ] `shouldBe` Nothing
 
     it "returns Nothing if the earliest non-empty line is closed" $
       openLineBy (openTerm "\n") [
-        Line True [ Info (Range 0 1) mempty :< Leaf "" ]
+        Line [ Info (Range 0 1) mempty :< Leaf "" ]
       ] `shouldBe` Nothing
 
   describe "openTerm" $ do
@@ -192,10 +192,10 @@ spec = do
 
     where
       rightRowText text = rightRow [ Text text ]
-      rightRow xs = Row EmptyLine (Line False xs)
+      rightRow xs = Row EmptyLine (Line xs)
       leftRowText text = leftRow [ Text text ]
-      leftRow xs = Row (Line False xs) EmptyLine
-      rowText a b = Row (Line False [ Text a ]) (Line False [ Text b ])
+      leftRow xs = Row (Line xs) EmptyLine
+      rowText a b = Row (Line [ Text a ]) (Line [ Text b ])
       info source category = Info (totalRange source)  (Set.fromList [ category ])
       unchanged source = formatted source source
       formatted source1 source2 category = Annotated (info source1 category, info source2 category)
@@ -203,5 +203,5 @@ spec = do
       offsetAnnotated by1 by2 (Annotated (left, right) syntax) = Annotated (offsetInfo by1 left, offsetInfo by2 right) syntax
       span = Span (Just "category-leaf")
       isOpen (Row a b) = Maybe.isJust (openLineBy openElement [ a ]) && Maybe.isJust (openLineBy openElement [ b ])
-      isClosed (Row a@(Line _ _) b@(Line _ _)) = Maybe.isNothing (openLineBy openElement [ a ]) && Maybe.isNothing (openLineBy openElement [ b ])
+      isClosed (Row a@(Line _) b@(Line _)) = Maybe.isNothing (openLineBy openElement [ a ]) && Maybe.isNothing (openLineBy openElement [ b ])
       isClosed (Row _ _) = False

From 38a317156b6dfcbd0400eb4ca422a68dfec78c8a Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 12:53:31 -0500
Subject: [PATCH 153/259] Move arbitrary term generation into its own module.

---
 semantic-diff.cabal   |  1 +
 test/ArbitraryTerm.hs | 47 +++++++++++++++++++++++++++++++++++++++++++
 test/TermSpec.hs      | 42 +-------------------------------------
 3 files changed, 49 insertions(+), 41 deletions(-)
 create mode 100644 test/ArbitraryTerm.hs

diff --git a/semantic-diff.cabal b/semantic-diff.cabal
index e123f0616..1bd11f497 100644
--- a/semantic-diff.cabal
+++ b/semantic-diff.cabal
@@ -77,6 +77,7 @@ test-suite semantic-diff-test
   type:                exitcode-stdio-1.0
   hs-source-dirs:      test
   main-is:             Spec.hs
+  other-modules:       ArbitraryTerm
   build-depends:       base
                      , containers
                      , free
diff --git a/test/ArbitraryTerm.hs b/test/ArbitraryTerm.hs
new file mode 100644
index 000000000..a91221bcc
--- /dev/null
+++ b/test/ArbitraryTerm.hs
@@ -0,0 +1,47 @@
+module ArbitraryTerm where
+
+import Categorizable
+import Syntax
+import Term
+import Control.Comonad.Cofree
+import Control.Monad
+import qualified OrderedMap as Map
+import qualified Data.List as List
+import qualified Data.Set as Set
+import GHC.Generics
+import Test.QuickCheck hiding (Fixed)
+
+newtype ArbitraryTerm a annotation = ArbitraryTerm (annotation, (Syntax a (ArbitraryTerm a annotation)))
+  deriving (Show, Eq, Generic)
+
+unTerm :: ArbitraryTerm a annotation -> Term a annotation
+unTerm = unfold unpack
+  where unpack (ArbitraryTerm (annotation, syntax)) = (annotation, syntax)
+
+instance (Eq a, Eq annotation, Arbitrary a, Arbitrary annotation) => Arbitrary (ArbitraryTerm a annotation) where
+  arbitrary = sized (\ x -> boundedTerm x x) -- first indicates the cube of the max length of lists, second indicates the cube of the max depth of the tree
+    where boundedTerm maxLength maxDepth = ArbitraryTerm <$> ((,) <$> arbitrary <*> boundedSyntax maxLength maxDepth)
+          boundedSyntax _ maxDepth | maxDepth <= 0 = liftM Leaf arbitrary
+          boundedSyntax maxLength maxDepth = frequency
+            [ (12, liftM Leaf arbitrary),
+              (1, liftM Indexed $ take maxLength <$> listOf (smallerTerm maxLength maxDepth)),
+              (1, liftM Fixed $ take maxLength <$> listOf (smallerTerm maxLength maxDepth)),
+              (1, liftM (Keyed . Map.fromList) $ take maxLength <$> listOf (arbitrary >>= (\x -> ((,) x) <$> smallerTerm maxLength maxDepth))) ]
+          smallerTerm maxLength maxDepth = boundedTerm (div maxLength 3) (div maxDepth 3)
+  shrink term@(ArbitraryTerm (annotation, syntax)) = (++) (subterms term) $ filter (/= term) $
+    ArbitraryTerm <$> ((,) <$> shrink annotation <*> case syntax of
+      Leaf a -> Leaf <$> shrink a
+      Indexed i -> Indexed <$> (List.subsequences i >>= recursivelyShrink)
+      Fixed f -> Fixed <$> (List.subsequences f >>= recursivelyShrink)
+      Keyed k -> Keyed . Map.fromList <$> (List.subsequences (Map.toList k) >>= recursivelyShrink))
+
+data CategorySet = A | B | C | D deriving (Eq, Show)
+
+instance Categorizable CategorySet where
+  categories A = Set.fromList [ "a" ]
+  categories B = Set.fromList [ "b" ]
+  categories C = Set.fromList [ "c" ]
+  categories D = Set.fromList [ "d" ]
+
+instance Arbitrary CategorySet where
+  arbitrary = elements [ A, B, C, D ]
diff --git a/test/TermSpec.hs b/test/TermSpec.hs
index 26e7dc582..c806198a1 100644
--- a/test/TermSpec.hs
+++ b/test/TermSpec.hs
@@ -5,51 +5,11 @@ import Test.Hspec.QuickCheck
 import Test.QuickCheck hiding (Fixed)
 
 import Categorizable
-import qualified OrderedMap as Map
-import qualified Data.List as List
-import qualified Data.Set as Set
 import Interpreter
 import Diff
-import Control.Comonad.Cofree
-import Control.Monad
-import GHC.Generics
 import Syntax
 import Term
-
-newtype ArbitraryTerm a annotation = ArbitraryTerm (annotation, (Syntax a (ArbitraryTerm a annotation)))
-  deriving (Show, Eq, Generic)
-
-unTerm :: ArbitraryTerm a annotation -> Term a annotation
-unTerm = unfold unpack
-  where unpack (ArbitraryTerm (annotation, syntax)) = (annotation, syntax)
-
-instance (Eq a, Eq annotation, Arbitrary a, Arbitrary annotation) => Arbitrary (ArbitraryTerm a annotation) where
-  arbitrary = sized (\ x -> boundedTerm x x) -- first indicates the cube of the max length of lists, second indicates the cube of the max depth of the tree
-    where boundedTerm maxLength maxDepth = ArbitraryTerm <$> ((,) <$> arbitrary <*> boundedSyntax maxLength maxDepth)
-          boundedSyntax _ maxDepth | maxDepth <= 0 = liftM Leaf arbitrary
-          boundedSyntax maxLength maxDepth = frequency
-            [ (12, liftM Leaf arbitrary),
-              (1, liftM Indexed $ take maxLength <$> listOf (smallerTerm maxLength maxDepth)),
-              (1, liftM Fixed $ take maxLength <$> listOf (smallerTerm maxLength maxDepth)),
-              (1, liftM (Keyed . Map.fromList) $ take maxLength <$> listOf (arbitrary >>= (\x -> ((,) x) <$> smallerTerm maxLength maxDepth))) ]
-          smallerTerm maxLength maxDepth = boundedTerm (div maxLength 3) (div maxDepth 3)
-  shrink term@(ArbitraryTerm (annotation, syntax)) = (++) (subterms term) $ filter (/= term) $
-    ArbitraryTerm <$> ((,) <$> shrink annotation <*> case syntax of
-      Leaf a -> Leaf <$> shrink a
-      Indexed i -> Indexed <$> (List.subsequences i >>= recursivelyShrink)
-      Fixed f -> Fixed <$> (List.subsequences f >>= recursivelyShrink)
-      Keyed k -> Keyed . Map.fromList <$> (List.subsequences (Map.toList k) >>= recursivelyShrink))
-
-data CategorySet = A | B | C | D deriving (Eq, Show)
-
-instance Categorizable CategorySet where
-  categories A = Set.fromList [ "a" ]
-  categories B = Set.fromList [ "b" ]
-  categories C = Set.fromList [ "c" ]
-  categories D = Set.fromList [ "d" ]
-
-instance Arbitrary CategorySet where
-  arbitrary = elements [ A, B, C, D ]
+import ArbitraryTerm
 
 main :: IO ()
 main = hspec spec

From 690966086e51d84fd9a168c6f6870f814d7c6f32 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 12:54:01 -0500
Subject: [PATCH 154/259] Remove some redundant parentheses.

---
 test/ArbitraryTerm.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/ArbitraryTerm.hs b/test/ArbitraryTerm.hs
index a91221bcc..6a64cf0ed 100644
--- a/test/ArbitraryTerm.hs
+++ b/test/ArbitraryTerm.hs
@@ -11,7 +11,7 @@ import qualified Data.Set as Set
 import GHC.Generics
 import Test.QuickCheck hiding (Fixed)
 
-newtype ArbitraryTerm a annotation = ArbitraryTerm (annotation, (Syntax a (ArbitraryTerm a annotation)))
+newtype ArbitraryTerm a annotation = ArbitraryTerm (annotation, Syntax a (ArbitraryTerm a annotation))
   deriving (Show, Eq, Generic)
 
 unTerm :: ArbitraryTerm a annotation -> Term a annotation
@@ -26,7 +26,7 @@ instance (Eq a, Eq annotation, Arbitrary a, Arbitrary annotation) => Arbitrary (
             [ (12, liftM Leaf arbitrary),
               (1, liftM Indexed $ take maxLength <$> listOf (smallerTerm maxLength maxDepth)),
               (1, liftM Fixed $ take maxLength <$> listOf (smallerTerm maxLength maxDepth)),
-              (1, liftM (Keyed . Map.fromList) $ take maxLength <$> listOf (arbitrary >>= (\x -> ((,) x) <$> smallerTerm maxLength maxDepth))) ]
+              (1, liftM (Keyed . Map.fromList) $ take maxLength <$> listOf (arbitrary >>= (\x -> (,) x <$> smallerTerm maxLength maxDepth))) ]
           smallerTerm maxLength maxDepth = boundedTerm (div maxLength 3) (div maxDepth 3)
   shrink term@(ArbitraryTerm (annotation, syntax)) = (++) (subterms term) $ filter (/= term) $
     ArbitraryTerm <$> ((,) <$> shrink annotation <*> case syntax of

From c4da8fb229d4df7483e36940b845f5cf1daad5c1 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 13:04:07 -0500
Subject: [PATCH 155/259] Generalize the single-line leaf test to arbitrary
 sources.

---
 test/SplitSpec.hs | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 7ee809fe6..560d9d3d7 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -12,6 +12,7 @@ import Control.Monad.Free hiding (unfold)
 import qualified Data.Maybe as Maybe
 import Patch
 import Syntax
+import ArbitraryTerm
 
 instance Arbitrary a => Arbitrary (Row a) where
   arbitrary = oneof [
@@ -31,6 +32,12 @@ instance Arbitrary a => Arbitrary (Line a) where
 spec :: Spec
 spec = do
   describe "splitAnnotatedByLines" $ do
+    prop "outputs one row for single-line unchanged leaves" $
+      \ a -> let source = filter (/= '\n') a
+                 range = totalRange source in
+                 splitAnnotatedByLines (source, source) (range, range) (mempty, mempty) (Leaf a) `shouldBe` [
+                   Row (Line [ Free $ Annotated (Info range mempty) $ Leaf a ]) (Line [ Free $ Annotated (Info range mempty) $ Leaf a ]) ]
+
     it "outputs one row for single-line unchanged leaves" $
       let sources = ("a", "a")
           ranges = (Range 0 1, Range 0 1)

From 2a8a87959016051c91307c5c5c1e7697b736e6a0 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 13:04:33 -0500
Subject: [PATCH 156/259] Remove the hard-coded test.

---
 test/SplitSpec.hs | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 560d9d3d7..e9d1206c9 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -38,12 +38,6 @@ spec = do
                  splitAnnotatedByLines (source, source) (range, range) (mempty, mempty) (Leaf a) `shouldBe` [
                    Row (Line [ Free $ Annotated (Info range mempty) $ Leaf a ]) (Line [ Free $ Annotated (Info range mempty) $ Leaf a ]) ]
 
-    it "outputs one row for single-line unchanged leaves" $
-      let sources = ("a", "a")
-          ranges = (Range 0 1, Range 0 1)
-          categories = (mempty, mempty) in
-          splitAnnotatedByLines sources ranges categories (Leaf "b") `shouldBe` [ Row (Line [ Free $ Annotated (Info (fst ranges) (fst categories)) $ Leaf "b" ]) (Line [ Free $ Annotated (Info (snd ranges) (snd categories)) $ Leaf "b" ]) ]
-
   describe "annotatedToRows" $ do
     it "outputs one row for single-line unchanged leaves" $
       annotatedToRows (unchanged "a" "leaf" (Leaf "")) "a" "a" `shouldBe` [ Row (Line [ span "a" ]) (Line [ span "a" ]) ]

From 867772d749532a113a08eb1dd8b93ee1cc719b53 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 13:04:39 -0500
Subject: [PATCH 157/259] Remove the corresponding annotatedToRows test.

---
 test/SplitSpec.hs | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index e9d1206c9..ea18bc63c 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -39,9 +39,6 @@ spec = do
                    Row (Line [ Free $ Annotated (Info range mempty) $ Leaf a ]) (Line [ Free $ Annotated (Info range mempty) $ Leaf a ]) ]
 
   describe "annotatedToRows" $ do
-    it "outputs one row for single-line unchanged leaves" $
-      annotatedToRows (unchanged "a" "leaf" (Leaf "")) "a" "a" `shouldBe` [ Row (Line [ span "a" ]) (Line [ span "a" ]) ]
-
     it "outputs one row for single-line empty unchanged indexed nodes" $
       annotatedToRows (unchanged "[]" "branch" (Indexed [])) "[]" "[]" `shouldBe` [ Row (Line [ Ul (Just "category-branch") [ Text "[]" ] ]) (Line [ Ul (Just "category-branch") [ Text "[]" ] ]) ]
 

From 0775f90ce46eada7f58c534a7876f0cbfc15f72e Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 13:06:37 -0500
Subject: [PATCH 158/259] Syntax highlight categories.

---
 src/Split.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index 5e5bf888a..dc15dff0a 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -136,7 +136,7 @@ type SplitDiff leaf annotation = Free (Annotated leaf annotation) (Term leaf ann
 newtype Renderable a = Renderable (String, a)
 
 instance ToMarkup f => ToMarkup (Renderable (Info, Syntax a (f, Range))) where
-  toMarkup (Renderable (source, (Info range categories, syntax))) = classifyMarkup (maybeLast categories) $ case syntax of
+  toMarkup (Renderable (source, (Info range categories, syntax))) = classifyMarkup (classify categories) $ case syntax of
     Leaf _ -> span . string $ substring range source
     Indexed children -> ul . mconcat $ contentElements children
     Fixed children -> ul . mconcat $ contentElements children

From 17a9de76ae38be4f303f6882ad08ddd313059335 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 13:09:02 -0500
Subject: [PATCH 159/259] Highlight patches within any code cell.

---
 UI/style.css | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/UI/style.css b/UI/style.css
index 1ede9c083..d4a481ea7 100644
--- a/UI/style.css
+++ b/UI/style.css
@@ -81,12 +81,12 @@ body {
   padding: 0;
   font-family: monospace;
 }
-.blob-code-replacement:last-child .insert,
-.blob-code-replacement:last-child .replace {
+.blob-code:last-child .insert,
+.blob-code:last-child .replace {
   background-color: #a6f3a6;
 }
-.blob-code-replacement .delete,
-.blob-code-replacement .replace {
+.blob-code .delete,
+.blob-code .replace {
   background-color: #f8cbcb;
 }
 

From 3d98361301ac4f36cca5a7031ef0b7049545eff9 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 13:09:10 -0500
Subject: [PATCH 160/259] Highlight the .patch class.

---
 UI/style.css | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/UI/style.css b/UI/style.css
index d4a481ea7..85681b3f3 100644
--- a/UI/style.css
+++ b/UI/style.css
@@ -81,10 +81,12 @@ body {
   padding: 0;
   font-family: monospace;
 }
+.blob-code:last-child .patch,
 .blob-code:last-child .insert,
 .blob-code:last-child .replace {
   background-color: #a6f3a6;
 }
+.blob-code .patch,
 .blob-code .delete,
 .blob-code .replace {
   background-color: #f8cbcb;

From aaaf8f27a438f5f2237dbd835929d71d09a43a76 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 13:16:03 -0500
Subject: [PATCH 161/259] Stub in a function to make arbitrary leaves & sources
 in some type.

---
 test/SplitSpec.hs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index ea18bc63c..c1b2177fd 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -29,6 +29,10 @@ instance Arbitrary a => Arbitrary (Line a) where
     Line <$> arbitrary,
     const EmptyLine <$> (arbitrary :: Gen ()) ]
 
+arbitraryLeaf :: Int -> (Info -> Syntax String f -> f) -> Gen (String, f)
+arbitraryLeaf start f = pairWithLeaf <$> arbitrary
+  where pairWithLeaf string = (string, f (Info (Range start $ start + length string) mempty) (Leaf string))
+
 spec :: Spec
 spec = do
   describe "splitAnnotatedByLines" $ do

From 0422098f9b4ab2f87b4ff844fcf6311008e838d8 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 13:29:12 -0500
Subject: [PATCH 162/259] =?UTF-8?q?`arbitraryLeaf`=20doesn=E2=80=99t=20con?=
 =?UTF-8?q?struct=20terms.?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 test/SplitSpec.hs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index c1b2177fd..2716008ac 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -29,9 +29,9 @@ instance Arbitrary a => Arbitrary (Line a) where
     Line <$> arbitrary,
     const EmptyLine <$> (arbitrary :: Gen ()) ]
 
-arbitraryLeaf :: Int -> (Info -> Syntax String f -> f) -> Gen (String, f)
-arbitraryLeaf start f = pairWithLeaf <$> arbitrary
-  where pairWithLeaf string = (string, f (Info (Range start $ start + length string) mempty) (Leaf string))
+arbitraryLeaf :: Int -> Gen (String, Info, Syntax String f)
+arbitraryLeaf start = pairWithLeaf <$> arbitrary
+  where pairWithLeaf string = (string, Info (Range start $ start + length string) mempty, Leaf string)
 
 spec :: Spec
 spec = do

From 5a552dc97c822450eb99adeb242e216d86c89054 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 13:29:36 -0500
Subject: [PATCH 163/259] Simplify the single-line unchanged leaf property.

---
 test/SplitSpec.hs | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 2716008ac..ce2d2338a 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -37,10 +37,9 @@ spec :: Spec
 spec = do
   describe "splitAnnotatedByLines" $ do
     prop "outputs one row for single-line unchanged leaves" $
-      \ a -> let source = filter (/= '\n') a
-                 range = totalRange source in
-                 splitAnnotatedByLines (source, source) (range, range) (mempty, mempty) (Leaf a) `shouldBe` [
-                   Row (Line [ Free $ Annotated (Info range mempty) $ Leaf a ]) (Line [ Free $ Annotated (Info range mempty) $ Leaf a ]) ]
+      forAll (arbitraryLeaf 0 `suchThat` \ (a, _, _) -> filter (/= '\n') a == a) $
+        \ (source, info@(Info range categories), syntax) -> splitAnnotatedByLines (source, source) (range, range) (categories, categories) syntax `shouldBe` [
+          Row (Line [ Free $ Annotated info $ Leaf source ]) (Line [ Free $ Annotated info $ Leaf source ]) ]
 
   describe "annotatedToRows" $ do
     it "outputs one row for single-line empty unchanged indexed nodes" $

From bf05d63401ef114d3a7c39d6d23c9a976e27255b Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 13:31:31 -0500
Subject: [PATCH 164/259] Rename the tripling function.

---
 test/SplitSpec.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index ce2d2338a..fc08fad68 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -30,8 +30,8 @@ instance Arbitrary a => Arbitrary (Line a) where
     const EmptyLine <$> (arbitrary :: Gen ()) ]
 
 arbitraryLeaf :: Int -> Gen (String, Info, Syntax String f)
-arbitraryLeaf start = pairWithLeaf <$> arbitrary
-  where pairWithLeaf string = (string, Info (Range start $ start + length string) mempty, Leaf string)
+arbitraryLeaf start = toTuple <$> arbitrary
+  where toTuple string = (string, Info (Range start $ start + length string) mempty, Leaf string)
 
 spec :: Spec
 spec = do

From b970f02c1d837a8c760c882e7c1ee84d8c7cadc2 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 13:38:44 -0500
Subject: [PATCH 165/259] =?UTF-8?q?Don=E2=80=99t=20offset=20arbitrary=20le?=
 =?UTF-8?q?aves.?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 test/SplitSpec.hs | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index fc08fad68..4cf26c2b2 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -29,15 +29,15 @@ instance Arbitrary a => Arbitrary (Line a) where
     Line <$> arbitrary,
     const EmptyLine <$> (arbitrary :: Gen ()) ]
 
-arbitraryLeaf :: Int -> Gen (String, Info, Syntax String f)
-arbitraryLeaf start = toTuple <$> arbitrary
-  where toTuple string = (string, Info (Range start $ start + length string) mempty, Leaf string)
+arbitraryLeaf :: Gen (String, Info, Syntax String f)
+arbitraryLeaf = toTuple <$> arbitrary
+  where toTuple string = (string, Info (Range 0 $ length string) mempty, Leaf string)
 
 spec :: Spec
 spec = do
   describe "splitAnnotatedByLines" $ do
     prop "outputs one row for single-line unchanged leaves" $
-      forAll (arbitraryLeaf 0 `suchThat` \ (a, _, _) -> filter (/= '\n') a == a) $
+      forAll (arbitraryLeaf `suchThat` \ (a, _, _) -> filter (/= '\n') a == a) $
         \ (source, info@(Info range categories), syntax) -> splitAnnotatedByLines (source, source) (range, range) (categories, categories) syntax `shouldBe` [
           Row (Line [ Free $ Annotated info $ Leaf source ]) (Line [ Free $ Annotated info $ Leaf source ]) ]
 

From 780c8247a39d119029bc9c7c98420d4ce0bc574f Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 14:44:49 -0500
Subject: [PATCH 166/259] Abstract out a predicate for terms on a single line.

---
 test/SplitSpec.hs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 4cf26c2b2..147decff4 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -206,3 +206,5 @@ spec = do
       isOpen (Row a b) = Maybe.isJust (openLineBy openElement [ a ]) && Maybe.isJust (openLineBy openElement [ b ])
       isClosed (Row a@(Line _) b@(Line _)) = Maybe.isNothing (openLineBy openElement [ a ]) && Maybe.isNothing (openLineBy openElement [ b ])
       isClosed (Row _ _) = False
+
+      isOnSingleLine (a, _, _) = filter (/= '\n') a == a

From b3c0802e552cf733b4c006103ef8a42ad2d348a8 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 14:44:57 -0500
Subject: [PATCH 167/259] Use the abstracted predicate.

---
 test/SplitSpec.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 147decff4..2257394ac 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -37,7 +37,7 @@ spec :: Spec
 spec = do
   describe "splitAnnotatedByLines" $ do
     prop "outputs one row for single-line unchanged leaves" $
-      forAll (arbitraryLeaf `suchThat` \ (a, _, _) -> filter (/= '\n') a == a) $
+      forAll (arbitraryLeaf `suchThat` isOnSingleLine) $
         \ (source, info@(Info range categories), syntax) -> splitAnnotatedByLines (source, source) (range, range) (categories, categories) syntax `shouldBe` [
           Row (Line [ Free $ Annotated info $ Leaf source ]) (Line [ Free $ Annotated info $ Leaf source ]) ]
 

From c41a2cfccce3203994917443316d9daa4d4a81e7 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 14:53:29 -0500
Subject: [PATCH 168/259] Enable RankNTypes.

---
 semantic-diff.cabal | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/semantic-diff.cabal b/semantic-diff.cabal
index 1bd11f497..6e063ebee 100644
--- a/semantic-diff.cabal
+++ b/semantic-diff.cabal
@@ -37,7 +37,7 @@ library
                      , blaze-html
                      , tree-sitter-parsers
   default-language:    Haskell2010
-  default-extensions:  DeriveFunctor, FlexibleInstances, DeriveFoldable, DeriveTraversable
+  default-extensions:  DeriveFunctor, FlexibleInstances, DeriveFoldable, DeriveTraversable, RankNTypes
   ghc-options:        -Wall -fno-warn-name-shadowing
 
 executable semantic-diff-exe

From b518c4702c631b57757d08a9b61cc4ad02768392 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 14:54:32 -0500
Subject: [PATCH 169/259] Add a function to find an open diff given a source
 string & left/right selector.

---
 src/Split.hs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/Split.hs b/src/Split.hs
index dc15dff0a..5b988a99c 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -330,6 +330,10 @@ openDiff :: String -> SplitDiff a Info -> Maybe (SplitDiff a Info)
 openDiff source diff@(Free (Annotated (Info range _) _)) = const diff <$> openRange source range
 openDiff source diff@(Pure term) = const diff <$> openTerm source term
 
+openDiff2 :: String -> (forall b. (b, b) -> b) -> Diff a Info -> Maybe (Diff a Info)
+openDiff2 source which diff@(Free (Annotated (Info range1 _, Info range2 _) _)) = const diff <$> openRange source (which (range1, range2))
+openDiff2 source which diff@(Pure patch) = const diff . openTerm source <$> which (before patch, after patch)
+
 openLineBy :: (a -> Maybe a) -> [Line a] -> Maybe (Line a)
 openLineBy _ [] = Nothing
 openLineBy f (EmptyLine : rest) = openLineBy f rest

From eaab1d73b282cd03a469f4ff1a95af2fa159da59 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 14:55:39 -0500
Subject: [PATCH 170/259] Rephrase openDiff2 to accept a pair of sources &
 apply the selector to the pair.

---
 src/Split.hs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 5b988a99c..5b0266d2a 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -330,9 +330,9 @@ openDiff :: String -> SplitDiff a Info -> Maybe (SplitDiff a Info)
 openDiff source diff@(Free (Annotated (Info range _) _)) = const diff <$> openRange source range
 openDiff source diff@(Pure term) = const diff <$> openTerm source term
 
-openDiff2 :: String -> (forall b. (b, b) -> b) -> Diff a Info -> Maybe (Diff a Info)
-openDiff2 source which diff@(Free (Annotated (Info range1 _, Info range2 _) _)) = const diff <$> openRange source (which (range1, range2))
-openDiff2 source which diff@(Pure patch) = const diff . openTerm source <$> which (before patch, after patch)
+openDiff2 :: (forall b. (b, b) -> b) -> (String, String) -> Diff a Info -> Maybe (Diff a Info)
+openDiff2 which sources diff@(Free (Annotated (Info range1 _, Info range2 _) _)) = const diff <$> openRange (which sources) (which (range1, range2))
+openDiff2 which sources diff@(Pure patch) = const diff . openTerm (which sources) <$> which (before patch, after patch)
 
 openLineBy :: (a -> Maybe a) -> [Line a] -> Maybe (Line a)
 openLineBy _ [] = Nothing

From 2768459246494c89ce712da0fc88bffd3457f6e5 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 15:13:04 -0500
Subject: [PATCH 171/259] Rename the string parameters in `split`.

---
 src/Split.hs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 5b0266d2a..508139a6d 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -52,7 +52,7 @@ instance ToMarkup HTML where
   toMarkup (Dt key) = dt $ string key
 
 split :: Diff a Info -> String -> String -> IO ByteString
-split diff before after = return . renderHtml
+split diff left right = return . renderHtml
   . docTypeHtml
     . ((head $ link ! A.rel (stringValue "stylesheet") ! A.href (stringValue "style.css")) <>)
     . body
@@ -60,8 +60,8 @@ split diff before after = return . renderHtml
         ((colgroup $ (col ! A.width (stringValue . show $ columnWidth)) <> col <> (col ! A.width (stringValue . show $ columnWidth)) <> col) <>)
         . mconcat $ toMarkup <$> reverse numbered
   where
-    rows = toRenderable <$> fst (splitDiffByLines diff (0, 0) (before, after))
-    toRenderable (Row a b) = Row (Renderable . (,) before <$> a) (Renderable . (,) after <$> b)
+    rows = toRenderable <$> fst (splitDiffByLines diff (0, 0) (left, right))
+    toRenderable (Row a b) = Row (Renderable . (,) left . split fst <$> a) (Renderable . (,) right . split snd <$> b)
     numbered = foldl numberRows [] rows
     maxNumber = case numbered of
       [] -> 0

From ecc1820a075bec6bc339a21685f390fe79bd6398 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 15:15:50 -0500
Subject: [PATCH 172/259] Add a recursive function to split a Diff into a
 SplitDiff.

---
 src/Split.hs | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/Split.hs b/src/Split.hs
index 508139a6d..97341caeb 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -71,6 +71,12 @@ split diff left right = return . renderHtml
     digits n = let base = 10 :: Int in
       ceiling (logBase (fromIntegral base) (fromIntegral n) :: Double)
 
+    split :: (forall b. (b, b) -> b) -> Free (Annotated leaf (annotation, annotation)) (Patch (Term leaf annotation)) -> SplitDiff leaf annotation
+    split which (Pure patch) = Pure $ case which (before patch, after patch) of
+      Just term -> term
+      _ -> error "`split` expects to be called with a total selector for patches"
+    split which (Free (Annotated infos syntax)) = Free . Annotated (which infos) $ split which <$> syntax
+
     columnWidth = max (20 + digits maxNumber * 8) 40
 
     numberRows :: [(Int, Line a, Int, Line a)] -> Row a -> [(Int, Line a, Int, Line a)]

From 5c27b16705f511b95e54a2d5dcaab855fae0e070 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 15:16:31 -0500
Subject: [PATCH 173/259] Fanout values into pairs.

---
 src/Split.hs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/Split.hs b/src/Split.hs
index 97341caeb..8387db74a 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -244,6 +244,7 @@ splitAnnotatedByLines sources ranges categories syntax = case syntax of
         starts (left, right) = (start left, start right)
         ends (left, right) = (end left, end right)
         makeRanges (leftStart, rightStart) (leftEnd, rightEnd) = (Range leftStart leftEnd, Range rightStart rightEnd)
+        duplicate x = (x, x)
 
 -- | Given an Annotated and before/after strings, returns a list of `Row`s representing the newline-separated diff.
 annotatedToRows :: Annotated a (Info, Info) (Diff a Info) -> String -> String -> [Row HTML]

From cff90ee11bdf07e83aec9a5ef93f4e02054aac32 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 15:17:17 -0500
Subject: [PATCH 174/259] Split diffs into left/right Diffs instead of
 SplitDiffs.

---
 src/Split.hs | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 8387db74a..0550bcc88 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -161,16 +161,16 @@ instance ToMarkup (Renderable (SplitDiff a Info)) where
     where toMarkupAndRange :: Term a Info -> (Markup, Range)
           toMarkupAndRange term@(Info range _ :< _) = ((div ! A.class_ (stringValue "patch")) . toMarkup $ Renderable (source, term), range)
 
-splitDiffByLines :: Diff a Info -> (Int, Int) -> (String, String) -> ([Row (SplitDiff a Info)], (Range, Range))
+splitDiffByLines :: Diff a Info -> (Int, Int) -> (String, String) -> ([Row (Diff a Info)], (Range, Range))
 splitDiffByLines diff (prevLeft, prevRight) sources = case diff of
   Free (Annotated annotation syntax) -> (splitAnnotatedByLines sources (ranges annotation) (categories annotation) syntax, ranges annotation)
   Pure (Insert term) -> let (lines, range) = splitTermByLines term (snd sources) in
-    (Row EmptyLine . fmap Pure <$> lines, (Range prevLeft prevLeft, range))
+    (Row EmptyLine . fmap (Pure . Insert) <$> lines, (Range prevLeft prevLeft, range))
   Pure (Delete term) -> let (lines, range) = splitTermByLines term (fst sources) in
-    (flip Row EmptyLine . fmap Pure <$> lines, (range, Range prevRight prevRight))
+    (flip Row EmptyLine . fmap (Pure . Delete) <$> lines, (range, Range prevRight prevRight))
   Pure (Replace leftTerm rightTerm) -> let (leftLines, leftRange) = splitTermByLines leftTerm (fst sources)
                                            (rightLines, rightRange) = splitTermByLines rightTerm (snd sources) in
-                                           (zipWithDefaults Row EmptyLine EmptyLine (fmap Pure <$> leftLines) (fmap Pure <$> rightLines), (leftRange, rightRange))
+                                           (zipWithDefaults Row EmptyLine EmptyLine (fmap (Pure . Delete) <$> leftLines) (fmap (Pure . Insert) <$> rightLines), (leftRange, rightRange))
   where categories (Info _ left, Info _ right) = (left, right)
         ranges (Info left _, Info right _) = (left, right)
 
@@ -226,15 +226,15 @@ termToLines (Info range categories :< syntax) source = (rows syntax, range)
       (adjoin $ lines ++ contextLines (Range previous $ start childRange) source ++ childLines, end childRange)
     elements = elementAndBreak (Span $ classify categories) =<< actualLines (substring range source)
 
-splitAnnotatedByLines :: (String, String) -> (Range, Range) -> (Set.Set Category, Set.Set Category) -> Syntax a (Diff a Info) -> [Row (SplitDiff a Info)]
+splitAnnotatedByLines :: (String, String) -> (Range, Range) -> (Set.Set Category, Set.Set Category) -> Syntax a (Diff a Info) -> [Row (Diff a Info)]
 splitAnnotatedByLines sources ranges categories syntax = case syntax of
   Leaf a -> contextRows (Leaf a) ranges categories sources
   Indexed children -> adjoinChildRows Indexed children
   Fixed children -> adjoinChildRows Fixed children
   Keyed children -> adjoinChildRows Keyed children
-  where contextRows constructor ranges categories sources = zipWithDefaults Row EmptyLine EmptyLine (contextLines (Free . (`Annotated` constructor)) (fst ranges) (fst categories) (fst sources)) (contextLines (Free . (`Annotated` constructor)) (snd ranges) (snd categories) (snd sources))
+  where contextRows constructor ranges categories sources = zipWithDefaults Row EmptyLine EmptyLine (contextLines (Free . (`Annotated` constructor) . duplicate) (fst ranges) (fst categories) (fst sources)) (contextLines (Free . (`Annotated` constructor) . duplicate) (snd ranges) (snd categories) (snd sources))
 
-        adjoin = reverse . foldl (adjoinRowsBy (openDiff $ fst sources) (openDiff $ snd sources)) []
+        adjoin = reverse . foldl (adjoinRowsBy (openDiff2 fst sources) (openDiff2 snd sources)) []
         adjoinChildRows constructor children = let (rows, previous) = foldl (childRows $ constructor mempty) ([], starts ranges) children in
           adjoin $ rows ++ contextRows (constructor mempty) (makeRanges previous (ends ranges)) categories sources
 

From 9cd5268642fc5c45fe6b79a12e34b65fc7e1faa3 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 15:17:21 -0500
Subject: [PATCH 175/259] Revert "Split diffs into left/right Diffs instead of
 SplitDiffs."

This reverts commit 1f71599a59b15f90fcd1a2c2f33b97b35c21ce65.
---
 src/Split.hs | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 0550bcc88..8387db74a 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -161,16 +161,16 @@ instance ToMarkup (Renderable (SplitDiff a Info)) where
     where toMarkupAndRange :: Term a Info -> (Markup, Range)
           toMarkupAndRange term@(Info range _ :< _) = ((div ! A.class_ (stringValue "patch")) . toMarkup $ Renderable (source, term), range)
 
-splitDiffByLines :: Diff a Info -> (Int, Int) -> (String, String) -> ([Row (Diff a Info)], (Range, Range))
+splitDiffByLines :: Diff a Info -> (Int, Int) -> (String, String) -> ([Row (SplitDiff a Info)], (Range, Range))
 splitDiffByLines diff (prevLeft, prevRight) sources = case diff of
   Free (Annotated annotation syntax) -> (splitAnnotatedByLines sources (ranges annotation) (categories annotation) syntax, ranges annotation)
   Pure (Insert term) -> let (lines, range) = splitTermByLines term (snd sources) in
-    (Row EmptyLine . fmap (Pure . Insert) <$> lines, (Range prevLeft prevLeft, range))
+    (Row EmptyLine . fmap Pure <$> lines, (Range prevLeft prevLeft, range))
   Pure (Delete term) -> let (lines, range) = splitTermByLines term (fst sources) in
-    (flip Row EmptyLine . fmap (Pure . Delete) <$> lines, (range, Range prevRight prevRight))
+    (flip Row EmptyLine . fmap Pure <$> lines, (range, Range prevRight prevRight))
   Pure (Replace leftTerm rightTerm) -> let (leftLines, leftRange) = splitTermByLines leftTerm (fst sources)
                                            (rightLines, rightRange) = splitTermByLines rightTerm (snd sources) in
-                                           (zipWithDefaults Row EmptyLine EmptyLine (fmap (Pure . Delete) <$> leftLines) (fmap (Pure . Insert) <$> rightLines), (leftRange, rightRange))
+                                           (zipWithDefaults Row EmptyLine EmptyLine (fmap Pure <$> leftLines) (fmap Pure <$> rightLines), (leftRange, rightRange))
   where categories (Info _ left, Info _ right) = (left, right)
         ranges (Info left _, Info right _) = (left, right)
 
@@ -226,15 +226,15 @@ termToLines (Info range categories :< syntax) source = (rows syntax, range)
       (adjoin $ lines ++ contextLines (Range previous $ start childRange) source ++ childLines, end childRange)
     elements = elementAndBreak (Span $ classify categories) =<< actualLines (substring range source)
 
-splitAnnotatedByLines :: (String, String) -> (Range, Range) -> (Set.Set Category, Set.Set Category) -> Syntax a (Diff a Info) -> [Row (Diff a Info)]
+splitAnnotatedByLines :: (String, String) -> (Range, Range) -> (Set.Set Category, Set.Set Category) -> Syntax a (Diff a Info) -> [Row (SplitDiff a Info)]
 splitAnnotatedByLines sources ranges categories syntax = case syntax of
   Leaf a -> contextRows (Leaf a) ranges categories sources
   Indexed children -> adjoinChildRows Indexed children
   Fixed children -> adjoinChildRows Fixed children
   Keyed children -> adjoinChildRows Keyed children
-  where contextRows constructor ranges categories sources = zipWithDefaults Row EmptyLine EmptyLine (contextLines (Free . (`Annotated` constructor) . duplicate) (fst ranges) (fst categories) (fst sources)) (contextLines (Free . (`Annotated` constructor) . duplicate) (snd ranges) (snd categories) (snd sources))
+  where contextRows constructor ranges categories sources = zipWithDefaults Row EmptyLine EmptyLine (contextLines (Free . (`Annotated` constructor)) (fst ranges) (fst categories) (fst sources)) (contextLines (Free . (`Annotated` constructor)) (snd ranges) (snd categories) (snd sources))
 
-        adjoin = reverse . foldl (adjoinRowsBy (openDiff2 fst sources) (openDiff2 snd sources)) []
+        adjoin = reverse . foldl (adjoinRowsBy (openDiff $ fst sources) (openDiff $ snd sources)) []
         adjoinChildRows constructor children = let (rows, previous) = foldl (childRows $ constructor mempty) ([], starts ranges) children in
           adjoin $ rows ++ contextRows (constructor mempty) (makeRanges previous (ends ranges)) categories sources
 

From 610133fdb3108030f72a09169ecc41581df9abcc Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 15:17:26 -0500
Subject: [PATCH 176/259] Revert "Fanout values into pairs."

This reverts commit 21bb26bb43b87d265ced27f30570283009822769.
---
 src/Split.hs | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index 8387db74a..97341caeb 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -244,7 +244,6 @@ splitAnnotatedByLines sources ranges categories syntax = case syntax of
         starts (left, right) = (start left, start right)
         ends (left, right) = (end left, end right)
         makeRanges (leftStart, rightStart) (leftEnd, rightEnd) = (Range leftStart leftEnd, Range rightStart rightEnd)
-        duplicate x = (x, x)
 
 -- | Given an Annotated and before/after strings, returns a list of `Row`s representing the newline-separated diff.
 annotatedToRows :: Annotated a (Info, Info) (Diff a Info) -> String -> String -> [Row HTML]

From 37afcfbc04d814a03c8c6a6e61db227f377a53f6 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 15:17:29 -0500
Subject: [PATCH 177/259] Revert "Add a recursive function to split a Diff into
 a SplitDiff."

This reverts commit e5ecdf3a0bbf3bd8a97dd210b8dedc6304e55e5d.
---
 src/Split.hs | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 97341caeb..508139a6d 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -71,12 +71,6 @@ split diff left right = return . renderHtml
     digits n = let base = 10 :: Int in
       ceiling (logBase (fromIntegral base) (fromIntegral n) :: Double)
 
-    split :: (forall b. (b, b) -> b) -> Free (Annotated leaf (annotation, annotation)) (Patch (Term leaf annotation)) -> SplitDiff leaf annotation
-    split which (Pure patch) = Pure $ case which (before patch, after patch) of
-      Just term -> term
-      _ -> error "`split` expects to be called with a total selector for patches"
-    split which (Free (Annotated infos syntax)) = Free . Annotated (which infos) $ split which <$> syntax
-
     columnWidth = max (20 + digits maxNumber * 8) 40
 
     numberRows :: [(Int, Line a, Int, Line a)] -> Row a -> [(Int, Line a, Int, Line a)]

From 73fd8b3d91e7fd85d94ca9a4582b7f83bd4de952 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 15:17:34 -0500
Subject: [PATCH 178/259] Revert "Rename the string parameters in `split`."

This reverts commit 46733254edb4a0ce79c49491753385622890758f.
---
 src/Split.hs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 508139a6d..5b0266d2a 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -52,7 +52,7 @@ instance ToMarkup HTML where
   toMarkup (Dt key) = dt $ string key
 
 split :: Diff a Info -> String -> String -> IO ByteString
-split diff left right = return . renderHtml
+split diff before after = return . renderHtml
   . docTypeHtml
     . ((head $ link ! A.rel (stringValue "stylesheet") ! A.href (stringValue "style.css")) <>)
     . body
@@ -60,8 +60,8 @@ split diff left right = return . renderHtml
         ((colgroup $ (col ! A.width (stringValue . show $ columnWidth)) <> col <> (col ! A.width (stringValue . show $ columnWidth)) <> col) <>)
         . mconcat $ toMarkup <$> reverse numbered
   where
-    rows = toRenderable <$> fst (splitDiffByLines diff (0, 0) (left, right))
-    toRenderable (Row a b) = Row (Renderable . (,) left . split fst <$> a) (Renderable . (,) right . split snd <$> b)
+    rows = toRenderable <$> fst (splitDiffByLines diff (0, 0) (before, after))
+    toRenderable (Row a b) = Row (Renderable . (,) before <$> a) (Renderable . (,) after <$> b)
     numbered = foldl numberRows [] rows
     maxNumber = case numbered of
       [] -> 0

From b6c4969bdd563f5eb136144f2ebfbe0cfa2c1a59 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 15:17:38 -0500
Subject: [PATCH 179/259] Revert "Rephrase openDiff2 to accept a pair of
 sources & apply the selector to the pair."

This reverts commit c22e9a3937f9bfdd91382fd20c29b681ccb18927.
---
 src/Split.hs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 5b0266d2a..5b988a99c 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -330,9 +330,9 @@ openDiff :: String -> SplitDiff a Info -> Maybe (SplitDiff a Info)
 openDiff source diff@(Free (Annotated (Info range _) _)) = const diff <$> openRange source range
 openDiff source diff@(Pure term) = const diff <$> openTerm source term
 
-openDiff2 :: (forall b. (b, b) -> b) -> (String, String) -> Diff a Info -> Maybe (Diff a Info)
-openDiff2 which sources diff@(Free (Annotated (Info range1 _, Info range2 _) _)) = const diff <$> openRange (which sources) (which (range1, range2))
-openDiff2 which sources diff@(Pure patch) = const diff . openTerm (which sources) <$> which (before patch, after patch)
+openDiff2 :: String -> (forall b. (b, b) -> b) -> Diff a Info -> Maybe (Diff a Info)
+openDiff2 source which diff@(Free (Annotated (Info range1 _, Info range2 _) _)) = const diff <$> openRange source (which (range1, range2))
+openDiff2 source which diff@(Pure patch) = const diff . openTerm source <$> which (before patch, after patch)
 
 openLineBy :: (a -> Maybe a) -> [Line a] -> Maybe (Line a)
 openLineBy _ [] = Nothing

From 7462ace01b6f32f8fc84e7b91782e2e41cf17ad7 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 15:17:44 -0500
Subject: [PATCH 180/259] Revert "Add a function to find an open diff given a
 source string & left/right selector."

This reverts commit 311f426726c3bbd409450444e3cc67d36510bbbe.
---
 src/Split.hs | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 5b988a99c..dc15dff0a 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -330,10 +330,6 @@ openDiff :: String -> SplitDiff a Info -> Maybe (SplitDiff a Info)
 openDiff source diff@(Free (Annotated (Info range _) _)) = const diff <$> openRange source range
 openDiff source diff@(Pure term) = const diff <$> openTerm source term
 
-openDiff2 :: String -> (forall b. (b, b) -> b) -> Diff a Info -> Maybe (Diff a Info)
-openDiff2 source which diff@(Free (Annotated (Info range1 _, Info range2 _) _)) = const diff <$> openRange source (which (range1, range2))
-openDiff2 source which diff@(Pure patch) = const diff . openTerm source <$> which (before patch, after patch)
-
 openLineBy :: (a -> Maybe a) -> [Line a] -> Maybe (Line a)
 openLineBy _ [] = Nothing
 openLineBy f (EmptyLine : rest) = openLineBy f rest

From 6e20ad6a9c5df51a41b730bdcefc68a03b8b0e61 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 15:17:55 -0500
Subject: [PATCH 181/259] Revert "Enable RankNTypes."

This reverts commit 8fce071dc9a45ff1ecb9d683980fc584a358eece.
---
 semantic-diff.cabal | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/semantic-diff.cabal b/semantic-diff.cabal
index 6e063ebee..1bd11f497 100644
--- a/semantic-diff.cabal
+++ b/semantic-diff.cabal
@@ -37,7 +37,7 @@ library
                      , blaze-html
                      , tree-sitter-parsers
   default-language:    Haskell2010
-  default-extensions:  DeriveFunctor, FlexibleInstances, DeriveFoldable, DeriveTraversable, RankNTypes
+  default-extensions:  DeriveFunctor, FlexibleInstances, DeriveFoldable, DeriveTraversable
   ghc-options:        -Wall -fno-warn-name-shadowing
 
 executable semantic-diff-exe

From 20817152c24d6dc5f81ac30872f16a29d640220e Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 15:20:46 -0500
Subject: [PATCH 182/259] Rename the line contents binding.

---
 src/Split.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index dc15dff0a..1191af80c 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -109,7 +109,7 @@ codeTd (Just el) = td el ! A.class_ (stringValue "blob-code")
 
 instance ToMarkup a => ToMarkup (Line a) where
   toMarkup EmptyLine = codeTd Nothing
-  toMarkup (Line html) = codeTd . Just . mconcat $ toMarkup <$> html
+  toMarkup (Line contents) = codeTd . Just . mconcat $ toMarkup <$> contents
 
 data Line a =
   Line [a]

From cf82488820224a1d43487984762c990260f669cf Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 15:29:16 -0500
Subject: [PATCH 183/259] =?UTF-8?q?codeTd=20takes=20a=20=E2=80=9Chas=20cha?=
 =?UTF-8?q?nges=E2=80=9D=20flag=20again.?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

We always pass `False` currently.
---
 src/Split.hs | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 1191af80c..2997bcdea 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -102,14 +102,14 @@ numberTd :: String -> Html
 numberTd "" = td mempty ! A.class_ (stringValue "blob-num blob-num-empty empty-cell")
 numberTd s = td (string s) ! A.class_ (stringValue "blob-num")
 
-codeTd :: Maybe Html -> Html
-codeTd Nothing = td mempty ! A.class_ (stringValue "blob-code blob-code-empty empty-cell")
--- codeTd True (Just el) = td el ! A.class_ (stringValue "blob-code blob-code-replacement")
-codeTd (Just el) = td el ! A.class_ (stringValue "blob-code")
+codeTd :: Bool -> Maybe Html -> Html
+codeTd _ Nothing = td mempty ! A.class_ (stringValue "blob-code blob-code-empty empty-cell")
+codeTd True (Just el) = td el ! A.class_ (stringValue "blob-code blob-code-replacement")
+codeTd False (Just el) = td el ! A.class_ (stringValue "blob-code")
 
 instance ToMarkup a => ToMarkup (Line a) where
-  toMarkup EmptyLine = codeTd Nothing
-  toMarkup (Line contents) = codeTd . Just . mconcat $ toMarkup <$> contents
+  toMarkup EmptyLine = codeTd False Nothing
+  toMarkup (Line contents) = codeTd False . Just . mconcat $ toMarkup <$> contents
 
 data Line a =
   Line [a]

From 9e6f415dc62d8b6d94c50eabcf3f2e62a33f1790 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 15:38:18 -0500
Subject: [PATCH 184/259] Port the single-line empty unchanged indexed diff
 test to splitAnnotatedByLines.

---
 test/SplitSpec.hs | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 2257394ac..8482cb5f8 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -41,6 +41,11 @@ spec = do
         \ (source, info@(Info range categories), syntax) -> splitAnnotatedByLines (source, source) (range, range) (categories, categories) syntax `shouldBe` [
           Row (Line [ Free $ Annotated info $ Leaf source ]) (Line [ Free $ Annotated info $ Leaf source ]) ]
 
+    prop "outputs one row for single-line empty unchanged indexed nodes" $
+      forAll (arbitrary `suchThat` \ s -> filter (/= '\n') s == s) $
+          \ source -> splitAnnotatedByLines (source, source) (totalRange source, totalRange source) (mempty, mempty) (Indexed [] :: Syntax String (Diff String Info)) `shouldBe` [
+            Row (Line [ Free $ Annotated (Info (totalRange source) mempty) $ Indexed [] ]) (Line [ Free $ Annotated (Info (totalRange source) mempty) $ Indexed [] ]) ]
+
   describe "annotatedToRows" $ do
     it "outputs one row for single-line empty unchanged indexed nodes" $
       annotatedToRows (unchanged "[]" "branch" (Indexed [])) "[]" "[]" `shouldBe` [ Row (Line [ Ul (Just "category-branch") [ Text "[]" ] ]) (Line [ Ul (Just "category-branch") [ Text "[]" ] ]) ]

From ef027dba367c5a6a2aeb280149b3a81bc358b95f Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 15:48:37 -0500
Subject: [PATCH 185/259] Test that we preserve the line counts in equal diffs.

---
 test/SplitSpec.hs | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 8482cb5f8..5cba2a075 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -46,6 +46,10 @@ spec = do
           \ source -> splitAnnotatedByLines (source, source) (totalRange source, totalRange source) (mempty, mempty) (Indexed [] :: Syntax String (Diff String Info)) `shouldBe` [
             Row (Line [ Free $ Annotated (Info (totalRange source) mempty) $ Indexed [] ]) (Line [ Free $ Annotated (Info (totalRange source) mempty) $ Indexed [] ]) ]
 
+    prop "preserves line counts in equal sources" $
+      \ source -> let range = totalRange source in
+        length (splitAnnotatedByLines (source, source) (totalRange source, totalRange source) (mempty, mempty) (Indexed . fst $ foldl combineIntoLeaves ([], 0) source)) `shouldBe` length (filter (== '\n') source) + 1
+
   describe "annotatedToRows" $ do
     it "outputs one row for single-line empty unchanged indexed nodes" $
       annotatedToRows (unchanged "[]" "branch" (Indexed [])) "[]" "[]" `shouldBe` [ Row (Line [ Ul (Just "category-branch") [ Text "[]" ] ]) (Line [ Ul (Just "category-branch") [ Text "[]" ] ]) ]
@@ -213,3 +217,5 @@ spec = do
       isClosed (Row _ _) = False
 
       isOnSingleLine (a, _, _) = filter (/= '\n') a == a
+
+      combineIntoLeaves (leaves, start) char = (leaves ++ [ Free $ Annotated (Info (Range start $ start + 1) mempty, Info (Range start $ start + 1) mempty) (Leaf [ char ]) ], start + 1)

From 603e750d67c5caa970e303a381753fb37d962b5b Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 15:55:59 -0500
Subject: [PATCH 186/259] Remove an unused let binding.

---
 test/SplitSpec.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 5cba2a075..e29ba6971 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -47,7 +47,7 @@ spec = do
             Row (Line [ Free $ Annotated (Info (totalRange source) mempty) $ Indexed [] ]) (Line [ Free $ Annotated (Info (totalRange source) mempty) $ Indexed [] ]) ]
 
     prop "preserves line counts in equal sources" $
-      \ source -> let range = totalRange source in
+      \ source ->
         length (splitAnnotatedByLines (source, source) (totalRange source, totalRange source) (mempty, mempty) (Indexed . fst $ foldl combineIntoLeaves ([], 0) source)) `shouldBe` length (filter (== '\n') source) + 1
 
   describe "annotatedToRows" $ do

From 6510e9552659552d5d043bbf1e2f3634cb73f792 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 16:10:05 -0500
Subject: [PATCH 187/259] Test that we always produce the maximum of the lines
 in two sources.

---
 test/SplitSpec.hs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index e29ba6971..9e708a393 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -50,6 +50,10 @@ spec = do
       \ source ->
         length (splitAnnotatedByLines (source, source) (totalRange source, totalRange source) (mempty, mempty) (Indexed . fst $ foldl combineIntoLeaves ([], 0) source)) `shouldBe` length (filter (== '\n') source) + 1
 
+    prop "produces the maximum line count in inequal sources" $
+      \ sourceA sourceB ->
+        length (splitAnnotatedByLines (sourceA, sourceB) (totalRange sourceA, totalRange sourceB) (mempty, mempty) (Indexed [])) `shouldBe` max (length (filter (== '\n') sourceA) + 1) (length (filter (== '\n') sourceB) + 1)
+
   describe "annotatedToRows" $ do
     it "outputs one row for single-line empty unchanged indexed nodes" $
       annotatedToRows (unchanged "[]" "branch" (Indexed [])) "[]" "[]" `shouldBe` [ Row (Line [ Ul (Just "category-branch") [ Text "[]" ] ]) (Line [ Ul (Just "category-branch") [ Text "[]" ] ]) ]

From 1b90bc02910e5101350599247cda353229756b60 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 16:26:07 -0500
Subject: [PATCH 188/259] Add a function to construct a leaf from a pair of
 line ranges.

---
 test/SplitSpec.hs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 9e708a393..ba731fa69 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -223,3 +223,5 @@ spec = do
       isOnSingleLine (a, _, _) = filter (/= '\n') a == a
 
       combineIntoLeaves (leaves, start) char = (leaves ++ [ Free $ Annotated (Info (Range start $ start + 1) mempty, Info (Range start $ start + 1) mempty) (Leaf [ char ]) ], start + 1)
+
+      leafWithRangesInSources sourceA sourceB rangeA rangeB = Free $ Annotated (Info rangeA mempty, Info rangeB mempty) (Leaf $ substring rangeA sourceA ++ substring rangeB sourceB)

From 9a496a6be58cc90698fe649d98a9fe1c1215210a Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 16:26:24 -0500
Subject: [PATCH 189/259] Populate the indexed term with leaves.

---
 test/SplitSpec.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index ba731fa69..b5ab74ba8 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -52,7 +52,7 @@ spec = do
 
     prop "produces the maximum line count in inequal sources" $
       \ sourceA sourceB ->
-        length (splitAnnotatedByLines (sourceA, sourceB) (totalRange sourceA, totalRange sourceB) (mempty, mempty) (Indexed [])) `shouldBe` max (length (filter (== '\n') sourceA) + 1) (length (filter (== '\n') sourceB) + 1)
+        length (splitAnnotatedByLines (sourceA, sourceB) (totalRange sourceA, totalRange sourceB) (mempty, mempty) (Indexed $ zipWith (leafWithRangesInSources sourceA sourceB) (actualLineRanges (totalRange sourceA) sourceA) (actualLineRanges (totalRange sourceB) sourceB))) `shouldBe` max (length (filter (== '\n') sourceA) + 1) (length (filter (== '\n') sourceB) + 1)
 
   describe "annotatedToRows" $ do
     it "outputs one row for single-line empty unchanged indexed nodes" $

From c41364a743cf58ea2674d38f178c719a30fcf1bf Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 16:28:49 -0500
Subject: [PATCH 190/259] Remove the remaining annotatedToRows tests.

---
 test/SplitSpec.hs | 80 -----------------------------------------------
 1 file changed, 80 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index b5ab74ba8..60528f73f 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -54,86 +54,6 @@ spec = do
       \ sourceA sourceB ->
         length (splitAnnotatedByLines (sourceA, sourceB) (totalRange sourceA, totalRange sourceB) (mempty, mempty) (Indexed $ zipWith (leafWithRangesInSources sourceA sourceB) (actualLineRanges (totalRange sourceA) sourceA) (actualLineRanges (totalRange sourceB) sourceB))) `shouldBe` max (length (filter (== '\n') sourceA) + 1) (length (filter (== '\n') sourceB) + 1)
 
-  describe "annotatedToRows" $ do
-    it "outputs one row for single-line empty unchanged indexed nodes" $
-      annotatedToRows (unchanged "[]" "branch" (Indexed [])) "[]" "[]" `shouldBe` [ Row (Line [ Ul (Just "category-branch") [ Text "[]" ] ]) (Line [ Ul (Just "category-branch") [ Text "[]" ] ]) ]
-
-    it "outputs one row for single-line non-empty unchanged indexed nodes" $
-      annotatedToRows (unchanged "[ a, b ]" "branch" (Indexed [
-        Free . offsetAnnotated 2 2 $ unchanged "a" "leaf" (Leaf ""),
-        Free . offsetAnnotated 5 5 $ unchanged "b" "leaf" (Leaf "")
-      ])) "[ a, b ]" "[ a, b ]" `shouldBe` [ Row (Line [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ", ", span "b", Text " ]" ] ]) (Line [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ", ", span "b", Text " ]" ] ]) ]
-
-    it "outputs one row for single-line non-empty formatted indexed nodes" $
-      annotatedToRows (formatted "[ a, b ]" "[ a,  b ]" "branch" (Indexed [
-        Free . offsetAnnotated 2 2 $ unchanged "a" "leaf" (Leaf ""),
-        Free . offsetAnnotated 5 6 $ unchanged "b" "leaf" (Leaf "")
-      ])) "[ a, b ]" "[ a,  b ]" `shouldBe` [ Row (Line [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ", ", span "b", Text " ]" ] ]) (Line [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ",  ", span "b", Text " ]" ] ]) ]
-
-    it "outputs two rows for two-line non-empty unchanged indexed nodes" $
-      annotatedToRows (unchanged "[ a,\nb ]" "branch" (Indexed [
-        Free . offsetAnnotated 2 2 $ unchanged "a" "leaf" (Leaf ""),
-        Free . offsetAnnotated 5 5 $ unchanged "b" "leaf" (Leaf "")
-      ])) "[ a,\nb ]" "[ a,\nb ]" `shouldBe`
-      [
-          Row (Line [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ",", Break ] ])
-              (Line [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ",", Break] ]),
-          Row (Line [ Ul (Just "category-branch") [ span "b", Text " ]" ] ])
-              (Line [ Ul (Just "category-branch") [ span "b", Text " ]" ] ])
-      ]
-
-    it "outputs two rows for two-line non-empty formatted indexed nodes" $
-      annotatedToRows (formatted "[ a,\nb ]" "[\na,\nb ]" "branch" (Indexed [
-        Free . offsetAnnotated 2 2 $ unchanged "a" "leaf" (Leaf ""),
-        Free . offsetAnnotated 5 5 $ unchanged "b" "leaf" (Leaf "")
-      ])) "[ a,\nb ]" "[\na,\nb ]" `shouldBe`
-      [
-          Row (Line [ Ul (Just "category-branch") [ Text "[ ", span "a", Text ",", Break ] ])
-              (Line [ Ul (Just "category-branch") [ Text "[", Break ] ]),
-          Row EmptyLine
-              (Line [ Ul (Just "category-branch") [ span "a", Text ",", Break ] ]),
-          Row (Line [ Ul (Just "category-branch") [ span "b", Text " ]" ] ])
-              (Line [ Ul (Just "category-branch") [ span "b", Text " ]" ] ])
-      ]
-
-    it "" $
-      let (sourceA, sourceB) = ("[\na\n,\nb]", "[a,b]") in
-        annotatedToRows (formatted sourceA sourceB "branch" (Indexed [
-          Free . offsetAnnotated 2 1 $ unchanged "a" "leaf" (Leaf ""),
-          Free . offsetAnnotated 6 3 $ unchanged "b" "leaf" (Leaf "")
-        ])) sourceA sourceB `shouldBe`
-        [
-            Row (Line [ Ul (Just "category-branch") [ Text "[", Break ] ])
-                (Line [ Ul (Just "category-branch") [ Text "[", span "a", Text ",", span "b", Text "]" ] ]),
-            Row (Line [ Ul (Just "category-branch") [ span "a", Break ] ])
-                EmptyLine,
-            Row (Line [ Ul (Just "category-branch") [ Text ",", Break ] ])
-                EmptyLine,
-            Row (Line [ Ul (Just "category-branch") [ span "b", Text "]" ] ])
-                EmptyLine
-        ]
-
-    it "splits multi-line deletions across multiple rows" $
-      let (sourceA, sourceB) = ("/*\n*/\na", "a") in
-        annotatedToRows (formatted sourceA sourceB "branch" (Indexed [
-          Pure . Delete $ (Info (Range 0 5) (Set.fromList ["leaf"]) :< Leaf ""),
-          Free . offsetAnnotated 6 0 $ unchanged "a" "leaf" (Leaf "")
-        ])) sourceA sourceB `shouldBe`
-        [
-          Row (Line [ Ul (Just "category-branch") [ Div (Just "delete") [ span "/*", Break ] ] ]) EmptyLine,
-          Row (Line [ Ul (Just "category-branch") [ Div (Just "delete") [ span "*/" ], Break ] ]) EmptyLine,
-          Row (Line [ Ul (Just "category-branch") [ span "a" ] ]) (Line [ Ul (Just "category-branch") [ span "a" ] ])
-        ]
-
-    describe "unicode" $
-      it "equivalent precomposed and decomposed characters are not equal" $
-        let (sourceA, sourceB) = ("t\776", "\7831")
-            syntax = Leaf . Pure $ Replace (info sourceA "leaf" :< Leaf "") (info sourceB "leaf" :< Leaf "")
-        in
-            annotatedToRows (formatted sourceA sourceB "leaf" syntax) sourceA sourceB `shouldBe`
-            [ Row (Line [ span "t\776" ]) (Line [ span "\7831"]) ]
-
-
   describe "adjoinRowsBy" $ do
     prop "is identity on top of no rows" $
       \ a -> adjoinRowsBy openElement openElement [] a == [ a ]

From ebb843ef4d413d927dda30527da5fc4bb6fefa6f Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 16:29:14 -0500
Subject: [PATCH 191/259] Remove the termToLines test.

---
 test/SplitSpec.hs | 9 ---------
 1 file changed, 9 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 60528f73f..1bf993eb8 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -75,15 +75,6 @@ spec = do
       forAll ((arbitrary `suchThat` isOpen) >>= \ a -> (,) a <$> (arbitrary `suchThat` isOpen)) $
         \ (a, b) -> adjoinRowsBy openElement openElement [ Row EmptyLine EmptyLine, a ] b `shouldBe` Row EmptyLine EmptyLine : adjoinRowsBy openElement openElement [ a ] b
 
-  describe "termToLines" $ do
-    it "splits multi-line terms into multiple lines" $
-      termToLines (Info (Range 0 5) (Set.singleton "leaf") :< Leaf "") "/*\n*/"
-      `shouldBe`
-      ([
-        Line [ span "/*", Break ],
-        Line [ span "*/" ]
-      ], Range 0 5)
-
   describe "splitTermByLines" $ do
     it "splits multi-line terms into multiple lines" $
       splitTermByLines (Info (Range 0 5) mempty :< Leaf "") "/*\n*/"

From bd3bee668aa479ceec779a19c3bafb4c6d2fd420 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 16:34:32 -0500
Subject: [PATCH 192/259] Generalize the splitTermByLines test across arbitrary
 strings.

---
 test/SplitSpec.hs | 10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 1bf993eb8..38de4c30c 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -76,13 +76,9 @@ spec = do
         \ (a, b) -> adjoinRowsBy openElement openElement [ Row EmptyLine EmptyLine, a ] b `shouldBe` Row EmptyLine EmptyLine : adjoinRowsBy openElement openElement [ a ] b
 
   describe "splitTermByLines" $ do
-    it "splits multi-line terms into multiple lines" $
-      splitTermByLines (Info (Range 0 5) mempty :< Leaf "") "/*\n*/"
-      `shouldBe`
-      ([
-        Line [ Info (Range 0 3) mempty :< Leaf "" ],
-        Line [ Info (Range 3 5) mempty :< Leaf "" ]
-      ], Range 0 5)
+    prop "preserves line count" $
+      \ source -> let range = totalRange source in
+        splitTermByLines (Info range mempty :< Leaf source) source `shouldBe` (Line . (:[]) . (:< Leaf source) . (`Info` mempty) <$> actualLineRanges range source, range)
 
   describe "openLineBy" $ do
     it "produces the earliest non-empty line in a list, if open" $

From bbbd874722b815378fea966e02599496009e5759 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 16:35:23 -0500
Subject: [PATCH 193/259] Remove the openLineBy tests using openElement.

---
 test/SplitSpec.hs | 12 ------------
 1 file changed, 12 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 38de4c30c..bbd3b8adb 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -81,24 +81,12 @@ spec = do
         splitTermByLines (Info range mempty :< Leaf source) source `shouldBe` (Line . (:[]) . (:< Leaf source) . (`Info` mempty) <$> actualLineRanges range source, range)
 
   describe "openLineBy" $ do
-    it "produces the earliest non-empty line in a list, if open" $
-      openLineBy openElement [
-        Line [ Div (Just "delete") [ span "*/" ] ],
-        Line [ Div (Just "delete") [ span " * Debugging", Break ] ],
-        Line [ Div (Just "delete") [ span "/*", Break ] ]
-      ] `shouldBe` (Just $ Line [ Div (Just "delete") [ span "*/" ] ])
-
     it "produces the earliest non-empty line in a list, if open" $
       openLineBy (openTerm "\n ") [
         Line [ Info (Range 1 2) mempty :< Leaf "" ],
         Line [ Info (Range 0 1) mempty :< Leaf "" ]
       ] `shouldBe` (Just $ Line [ Info (Range 1 2) mempty :< Leaf "" ])
 
-    it "returns Nothing if the earliest non-empty line is closed" $
-      openLineBy openElement [
-        Line [ Div (Just "delete") [ span " * Debugging", Break ] ]
-      ] `shouldBe` Nothing
-
     it "returns Nothing if the earliest non-empty line is closed" $
       openLineBy (openTerm "\n") [
         Line [ Info (Range 0 1) mempty :< Leaf "" ]

From 6607f0d605be76c4d5a18010b501639d4a8ac29f Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 16:39:43 -0500
Subject: [PATCH 194/259] Remove diffToRows & annotatedToRows.

---
 src/Split.hs | 44 --------------------------------------------
 1 file changed, 44 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 2997bcdea..27eaafb19 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -13,7 +13,6 @@ import Text.Blaze.Html
 import Text.Blaze.Html5 hiding (map)
 import qualified Text.Blaze.Html5.Attributes as A
 import Text.Blaze.Html.Renderer.Utf8
-import qualified OrderedMap as Map
 import Data.Monoid
 import qualified Data.Set as Set
 import Data.List (intercalate)
@@ -168,25 +167,6 @@ splitDiffByLines diff (prevLeft, prevRight) sources = case diff of
   where categories (Info _ left, Info _ right) = (left, right)
         ranges (Info left _, Info right _) = (left, right)
 
-diffToRows :: Diff a Info -> (Int, Int) -> String -> String -> ([Row HTML], (Range, Range))
-diffToRows (Free annotated@(Annotated (Info left _, Info right _) _)) _ before after = (annotatedToRows annotated before after, (left, right))
-diffToRows (Pure (Insert term)) (previousIndex, _) _ after = (rowWithInsertedLine <$> afterLines, (Range previousIndex previousIndex, range))
-  where
-    (afterLines, range) = termToLines term after
-    rowWithInsertedLine (Line elements) = Row EmptyLine $ Line [ Div (Just "insert") elements ]
-    rowWithInsertedLine line = Row line line
-diffToRows (Pure (Delete term)) (_, previousIndex) before _ = (rowWithDeletedLine <$> lines, (range, Range previousIndex previousIndex))
-  where
-    (lines, range) = termToLines term before
-    rowWithDeletedLine (Line elements) = Row (Line [ Div (Just "delete") elements ]) EmptyLine
-    rowWithDeletedLine line = Row line line
-diffToRows (Pure (Replace a b)) _ before after = (replacedRows, (leftRange, rightRange))
-  where
-    replacedRows = zipWithMaybe rowFromMaybeRows (replace <$> leftElements) (replace <$> rightElements)
-    replace = Div (Just "replace") . unLine
-    (leftElements, leftRange) = termToLines a before
-    (rightElements, rightRange) = termToLines b after
-
 -- | Takes a term and a source and returns a list of lines and their range within source.
 splitTermByLines :: Term a Info -> String -> ([Line (Term a Info)], Range)
 splitTermByLines (Info range categories :< syntax) source = flip (,) range $ case syntax of
@@ -239,30 +219,6 @@ splitAnnotatedByLines sources ranges categories syntax = case syntax of
         ends (left, right) = (end left, end right)
         makeRanges (leftStart, rightStart) (leftEnd, rightEnd) = (Range leftStart leftEnd, Range rightStart rightEnd)
 
--- | Given an Annotated and before/after strings, returns a list of `Row`s representing the newline-separated diff.
-annotatedToRows :: Annotated a (Info, Info) (Diff a Info) -> String -> String -> [Row HTML]
-annotatedToRows (Annotated (Info left leftCategories, Info right rightCategories) syntax) before after = rows syntax
-  where
-    rows (Leaf _) = zipWithMaybe rowFromMaybeRows leftElements rightElements
-    rows (Indexed i) = rewrapRowContentsIn Ul <$> childRows i
-    rows (Fixed f) = rewrapRowContentsIn Ul <$> childRows f
-    rows (Keyed k) = rewrapRowContentsIn Dl <$> childRows (snd <$> Map.toList k)
-
-    leftElements = elementAndBreak (Span $ classify leftCategories) =<< actualLines (substring left before)
-    rightElements = elementAndBreak (Span $ classify rightCategories) =<< actualLines (substring right after)
-
-    wrap _ EmptyLine = EmptyLine
-    wrap f (Line elements) = Line [ f elements ]
-    rewrapRowContentsIn f (Row left right) = Row (wrap (f $ classify leftCategories) left) (wrap (f $ classify rightCategories) right)
-    ranges = (left, right)
-    sources = (before, after)
-    childRows = appendRemainder . foldl sumRows ([], starts ranges)
-    appendRemainder (rows, previousIndices) = reverse . foldl (adjoinRowsBy openElement openElement) [] $ rows ++ contextRows (ends ranges) previousIndices sources
-    starts (left, right) = (start left, start right)
-    ends (left, right) = (end left, end right)
-    sumRows (rows, previousIndices) child = let (childRows, childRanges) = diffToRows child previousIndices before after in
-      (rows ++ contextRows (starts childRanges) previousIndices sources ++ childRows, ends childRanges)
-
 contextLines :: (Info -> a) -> Range -> Set.Set Category -> String -> [Line a]
 contextLines constructor range categories source = Line . (:[]) . constructor . (`Info` categories) <$> actualLineRanges range source
 

From 39e318317f698f80415b45d5b1d802755bda49ce Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 16:40:20 -0500
Subject: [PATCH 195/259] Remove termToLines.

---
 src/Split.hs | 19 -------------------
 1 file changed, 19 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 27eaafb19..1b7b1e2c8 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -181,25 +181,6 @@ splitTermByLines (Info range categories :< syntax) source = flip (,) range $ cas
         childLines constructor (lines, previous) child = let (childLines, childRange) = splitTermByLines child source in
           (adjoin $ lines ++ contextLines (:< constructor) (Range previous $ start childRange) categories source ++ childLines, end childRange)
 
--- | Takes a term and a source and returns a list of lines and their range within source.
-termToLines :: Term a Info -> String -> ([Line HTML], Range)
-termToLines (Info range categories :< syntax) source = (rows syntax, range)
-  where
-    rows (Leaf _) = adjoin $ Line . (:[]) <$> elements
-    rows (Indexed i) = rewrapLineContentsIn (Ul $ classify categories) <$> childLines i
-    rows (Fixed f) = rewrapLineContentsIn (Ul $ classify categories) <$> childLines f
-    rows (Keyed k) = rewrapLineContentsIn (Dl $ classify categories) <$> childLines k
-
-    adjoin = reverse . foldl (adjoinLinesBy openElement) []
-    rewrapLineContentsIn f (Line elements) = Line [ f elements ]
-    rewrapLineContentsIn _ EmptyLine = EmptyLine
-    contextLines r s = Line . (:[]) <$> textElements r s
-    childLines i = let (lines, previous) = foldl sumLines ([], start range) i in
-      adjoin $ lines ++ contextLines (Range previous (end range)) source
-    sumLines (lines, previous) child = let (childLines, childRange) = termToLines child source in
-      (adjoin $ lines ++ contextLines (Range previous $ start childRange) source ++ childLines, end childRange)
-    elements = elementAndBreak (Span $ classify categories) =<< actualLines (substring range source)
-
 splitAnnotatedByLines :: (String, String) -> (Range, Range) -> (Set.Set Category, Set.Set Category) -> Syntax a (Diff a Info) -> [Row (SplitDiff a Info)]
 splitAnnotatedByLines sources ranges categories syntax = case syntax of
   Leaf a -> contextRows (Leaf a) ranges categories sources

From 1f8b9b9ae9a6a20d7b8b8d0b0dd0d0e82e6fb8cc Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 16:41:17 -0500
Subject: [PATCH 196/259] Remove the global contextRows definition.

---
 src/Split.hs | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 1b7b1e2c8..6c2c4b958 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -203,12 +203,6 @@ splitAnnotatedByLines sources ranges categories syntax = case syntax of
 contextLines :: (Info -> a) -> Range -> Set.Set Category -> String -> [Line a]
 contextLines constructor range categories source = Line . (:[]) . constructor . (`Info` categories) <$> actualLineRanges range source
 
-contextRows :: (Int, Int) -> (Int, Int) -> (String, String) -> [Row HTML]
-contextRows childIndices previousIndices sources = zipWithMaybe rowFromMaybeRows leftElements rightElements
-  where
-    leftElements = textElements (Range (fst previousIndices) (fst childIndices)) (fst sources)
-    rightElements = textElements (Range (snd previousIndices) (snd childIndices)) (snd sources)
-
 elementAndBreak :: (String -> HTML) -> String -> [HTML]
 elementAndBreak _ "" = []
 elementAndBreak _ "\n" = [ Break ]

From 4070c8f271f6487e1e577a5de3c7396061a3784a Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 16:41:52 -0500
Subject: [PATCH 197/259] Remove the textElements definition.

---
 src/Split.hs | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 6c2c4b958..dd4a2f9f2 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -209,10 +209,6 @@ elementAndBreak _ "\n" = [ Break ]
 elementAndBreak constructor x | '\n' <- last x = [ constructor $ init x, Break ]
 elementAndBreak constructor x = [ constructor x ]
 
-textElements :: Range -> String -> [HTML]
-textElements range source = elementAndBreak Text =<< actualLines s
-  where s = substring range source
-
 rowFromMaybeRows :: Maybe a -> Maybe a -> Row a
 rowFromMaybeRows a b = Row (maybe EmptyLine (Line . (:[])) a) (maybe EmptyLine (Line . (:[])) b)
 

From c3a9b4f5d1bcd251ec42f3242524443f890133b0 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 16:42:03 -0500
Subject: [PATCH 198/259] Remove the rowFromMaybeRows definition.

---
 src/Split.hs | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index dd4a2f9f2..0ba1d92f4 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -209,9 +209,6 @@ elementAndBreak _ "\n" = [ Break ]
 elementAndBreak constructor x | '\n' <- last x = [ constructor $ init x, Break ]
 elementAndBreak constructor x = [ constructor x ]
 
-rowFromMaybeRows :: Maybe a -> Maybe a -> Row a
-rowFromMaybeRows a b = Row (maybe EmptyLine (Line . (:[])) a) (maybe EmptyLine (Line . (:[])) b)
-
 maybeLast :: Foldable f => f a -> Maybe a
 maybeLast = foldl (flip $ const . Just) Nothing
 

From 1d0aecda802a65b16df198b88f823b49811df0a9 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 16:42:27 -0500
Subject: [PATCH 199/259] Remove the zipWithMaybe definition.

---
 src/Split.hs | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 0ba1d92f4..7330e0750 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -265,9 +265,6 @@ adjoinLinesBy f (EmptyLine : xs) line | Just _ <- openLineBy f xs = EmptyLine :
 adjoinLinesBy f (prev:rest) line | Just _ <- openLineBy f [ prev ] = (prev <> line) : rest
 adjoinLinesBy _ lines line = line : lines
 
-zipWithMaybe :: (Maybe a -> Maybe b -> c) -> [a] -> [b] -> [c]
-zipWithMaybe f a b = zipWithDefaults f Nothing Nothing (Just <$> a) (Just <$> b)
-
 zipWithDefaults :: (a -> b -> c) -> a -> b -> [a] -> [b] -> [c]
 zipWithDefaults f da db a b = take (max (length a) (length b)) $ zipWith f (a ++ repeat da) (b ++ repeat db)
 

From 97d868ad26d1cbe20993acc99eeabd9b426ad085 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 16:42:57 -0500
Subject: [PATCH 200/259] Remove elementAndBreak.

---
 src/Split.hs | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 7330e0750..6be3765f6 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -203,12 +203,6 @@ splitAnnotatedByLines sources ranges categories syntax = case syntax of
 contextLines :: (Info -> a) -> Range -> Set.Set Category -> String -> [Line a]
 contextLines constructor range categories source = Line . (:[]) . constructor . (`Info` categories) <$> actualLineRanges range source
 
-elementAndBreak :: (String -> HTML) -> String -> [HTML]
-elementAndBreak _ "" = []
-elementAndBreak _ "\n" = [ Break ]
-elementAndBreak constructor x | '\n' <- last x = [ constructor $ init x, Break ]
-elementAndBreak constructor x = [ constructor x ]
-
 maybeLast :: Foldable f => f a -> Maybe a
 maybeLast = foldl (flip $ const . Just) Nothing
 

From 0d33052528a142d62a7e3b7f1883aab8121b3a10 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 16:44:06 -0500
Subject: [PATCH 201/259] Remove the ToMarkup instance for HTML.

---
 src/Split.hs | 17 -----------------
 1 file changed, 17 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 6be3765f6..9560a6312 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -33,23 +33,6 @@ classifyMarkup :: Maybe ClassName -> Markup -> Markup
 classifyMarkup (Just className) element = element ! A.class_ (stringValue className)
 classifyMarkup _ element = element
 
-toLi :: HTML -> Markup
-toLi (Text s) = string s
-toLi e = li $ toMarkup e
-
-toDd :: HTML -> Markup
-toDd (Text s) = string s
-toDd e = dd $ toMarkup e
-
-instance ToMarkup HTML where
-  toMarkup Break = br
-  toMarkup (Text s) = string s
-  toMarkup (Span className s) = classifyMarkup className . span $ string s
-  toMarkup (Ul className children) = classifyMarkup className . ul $ mconcat (toLi <$> children)
-  toMarkup (Dl className children) = classifyMarkup className . dl $ mconcat (toDd <$> children)
-  toMarkup (Div className children) = classifyMarkup className . div $ mconcat (toMarkup <$> children)
-  toMarkup (Dt key) = dt $ string key
-
 split :: Diff a Info -> String -> String -> IO ByteString
 split diff before after = return . renderHtml
   . docTypeHtml

From 3adfd06d5a00ede0265c3181f85fd0422a30e76f Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 16:52:20 -0500
Subject: [PATCH 202/259] Add an open string selector.

---
 test/SplitSpec.hs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index bbd3b8adb..fba9c52e5 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -120,3 +120,5 @@ spec = do
       combineIntoLeaves (leaves, start) char = (leaves ++ [ Free $ Annotated (Info (Range start $ start + 1) mempty, Info (Range start $ start + 1) mempty) (Leaf [ char ]) ], start + 1)
 
       leafWithRangesInSources sourceA sourceB rangeA rangeB = Free $ Annotated (Info rangeA mempty, Info rangeB mempty) (Leaf $ substring rangeA sourceA ++ substring rangeB sourceB)
+
+      openString string = const string <$> openRange string (totalRange string)

From 8599fd46d9f7cbf64798ea15dc69de9156a59e78 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 16:52:36 -0500
Subject: [PATCH 203/259] Test adjoinRowsBy using openString.

---
 test/SplitSpec.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index fba9c52e5..550c69ce2 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -56,7 +56,7 @@ spec = do
 
   describe "adjoinRowsBy" $ do
     prop "is identity on top of no rows" $
-      \ a -> adjoinRowsBy openElement openElement [] a == [ a ]
+      \ a -> adjoinRowsBy openString openString [] a == [ a ]
 
     prop "appends onto open rows" $
       forAll ((arbitrary `suchThat` isOpen) >>= \ a -> (,) a <$> (arbitrary `suchThat` isOpen)) $

From 631e572ab3b8e90f9aa3a8ce86d511eabaab6e1d Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 16:55:13 -0500
Subject: [PATCH 204/259] Generalize the isClosed predicate.

---
 test/SplitSpec.hs | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 550c69ce2..b61a20a53 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -64,11 +64,11 @@ spec = do
           adjoinRowsBy openElement openElement [ a ] b `shouldBe` [ Row (Line $ a1 ++ a2) (Line $ b1 ++ b2) ]
 
     prop "does not append onto closed rows" $
-      forAll ((arbitrary `suchThat` isClosed) >>= \ a -> (,) a <$> (arbitrary `suchThat` isClosed)) $
+      forAll ((arbitrary `suchThat` isClosedBy openElement) >>= \ a -> (,) a <$> (arbitrary `suchThat` isClosedBy openElement)) $
         \ (a, b) -> adjoinRowsBy openElement openElement [ a ] b `shouldBe` [ b, a ]
 
     prop "does not promote elements through empty lines onto closed lines" $
-      forAll ((arbitrary `suchThat` isClosed) >>= \ a -> (,) a <$> (arbitrary `suchThat` isClosed)) $
+      forAll ((arbitrary `suchThat` isClosedBy openElement) >>= \ a -> (,) a <$> (arbitrary `suchThat` isClosedBy openElement)) $
         \ (a, b) -> adjoinRowsBy openElement openElement [ Row EmptyLine EmptyLine, a ] b `shouldBe` [ b, Row EmptyLine EmptyLine, a ]
 
     prop "promotes elements through empty lines onto open lines" $
@@ -112,8 +112,8 @@ spec = do
       offsetAnnotated by1 by2 (Annotated (left, right) syntax) = Annotated (offsetInfo by1 left, offsetInfo by2 right) syntax
       span = Span (Just "category-leaf")
       isOpen (Row a b) = Maybe.isJust (openLineBy openElement [ a ]) && Maybe.isJust (openLineBy openElement [ b ])
-      isClosed (Row a@(Line _) b@(Line _)) = Maybe.isNothing (openLineBy openElement [ a ]) && Maybe.isNothing (openLineBy openElement [ b ])
-      isClosed (Row _ _) = False
+      isClosedBy f (Row a@(Line _) b@(Line _)) = Maybe.isNothing (openLineBy f [ a ]) && Maybe.isNothing (openLineBy f [ b ])
+      isClosedBy _ (Row _ _) = False
 
       isOnSingleLine (a, _, _) = filter (/= '\n') a == a
 

From cfa82876c1ec008f8e732a9af2d7c68495fe0ffc Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 16:55:18 -0500
Subject: [PATCH 205/259] Generalize the isOpen predicate.

---
 test/SplitSpec.hs | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index b61a20a53..7de74e5f2 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -59,7 +59,7 @@ spec = do
       \ a -> adjoinRowsBy openString openString [] a == [ a ]
 
     prop "appends onto open rows" $
-      forAll ((arbitrary `suchThat` isOpen) >>= \ a -> (,) a <$> (arbitrary `suchThat` isOpen)) $
+      forAll ((arbitrary `suchThat` isOpenBy openElement) >>= \ a -> (,) a <$> (arbitrary `suchThat` isOpenBy openElement)) $
         \ (a@(Row (Line a1) (Line b1)), b@(Row (Line a2) (Line b2))) ->
           adjoinRowsBy openElement openElement [ a ] b `shouldBe` [ Row (Line $ a1 ++ a2) (Line $ b1 ++ b2) ]
 
@@ -72,7 +72,7 @@ spec = do
         \ (a, b) -> adjoinRowsBy openElement openElement [ Row EmptyLine EmptyLine, a ] b `shouldBe` [ b, Row EmptyLine EmptyLine, a ]
 
     prop "promotes elements through empty lines onto open lines" $
-      forAll ((arbitrary `suchThat` isOpen) >>= \ a -> (,) a <$> (arbitrary `suchThat` isOpen)) $
+      forAll ((arbitrary `suchThat` isOpenBy openElement) >>= \ a -> (,) a <$> (arbitrary `suchThat` isOpenBy openElement)) $
         \ (a, b) -> adjoinRowsBy openElement openElement [ Row EmptyLine EmptyLine, a ] b `shouldBe` Row EmptyLine EmptyLine : adjoinRowsBy openElement openElement [ a ] b
 
   describe "splitTermByLines" $ do
@@ -111,7 +111,7 @@ spec = do
       offsetInfo by (Info (Range start end) categories) = Info (Range (start + by) (end + by)) categories
       offsetAnnotated by1 by2 (Annotated (left, right) syntax) = Annotated (offsetInfo by1 left, offsetInfo by2 right) syntax
       span = Span (Just "category-leaf")
-      isOpen (Row a b) = Maybe.isJust (openLineBy openElement [ a ]) && Maybe.isJust (openLineBy openElement [ b ])
+      isOpenBy f (Row a b) = Maybe.isJust (openLineBy f [ a ]) && Maybe.isJust (openLineBy f [ b ])
       isClosedBy f (Row a@(Line _) b@(Line _)) = Maybe.isNothing (openLineBy f [ a ]) && Maybe.isNothing (openLineBy f [ b ])
       isClosedBy _ (Row _ _) = False
 

From 8c71fff97a11f68cfdf2face714d83b57e98f928 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 16:55:53 -0500
Subject: [PATCH 206/259] Test appending onto open rows over strings.

---
 test/SplitSpec.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 7de74e5f2..f7581a53d 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -59,9 +59,9 @@ spec = do
       \ a -> adjoinRowsBy openString openString [] a == [ a ]
 
     prop "appends onto open rows" $
-      forAll ((arbitrary `suchThat` isOpenBy openElement) >>= \ a -> (,) a <$> (arbitrary `suchThat` isOpenBy openElement)) $
+      forAll ((arbitrary `suchThat` isOpenBy openString) >>= \ a -> (,) a <$> (arbitrary `suchThat` isOpenBy openString)) $
         \ (a@(Row (Line a1) (Line b1)), b@(Row (Line a2) (Line b2))) ->
-          adjoinRowsBy openElement openElement [ a ] b `shouldBe` [ Row (Line $ a1 ++ a2) (Line $ b1 ++ b2) ]
+          adjoinRowsBy openString openString [ a ] b `shouldBe` [ Row (Line $ a1 ++ a2) (Line $ b1 ++ b2) ]
 
     prop "does not append onto closed rows" $
       forAll ((arbitrary `suchThat` isClosedBy openElement) >>= \ a -> (,) a <$> (arbitrary `suchThat` isClosedBy openElement)) $

From c643f2ed5804934b18bc0350e255258a2beb526a Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 16:56:22 -0500
Subject: [PATCH 207/259] Test not appending onto closed rows over strings.

---
 test/SplitSpec.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index f7581a53d..50c5a8756 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -64,8 +64,8 @@ spec = do
           adjoinRowsBy openString openString [ a ] b `shouldBe` [ Row (Line $ a1 ++ a2) (Line $ b1 ++ b2) ]
 
     prop "does not append onto closed rows" $
-      forAll ((arbitrary `suchThat` isClosedBy openElement) >>= \ a -> (,) a <$> (arbitrary `suchThat` isClosedBy openElement)) $
-        \ (a, b) -> adjoinRowsBy openElement openElement [ a ] b `shouldBe` [ b, a ]
+      forAll ((arbitrary `suchThat` isClosedBy openString) >>= \ a -> (,) a <$> (arbitrary `suchThat` isClosedBy openString)) $
+        \ (a, b) -> adjoinRowsBy openString openString [ a ] b `shouldBe` [ b, a ]
 
     prop "does not promote elements through empty lines onto closed lines" $
       forAll ((arbitrary `suchThat` isClosedBy openElement) >>= \ a -> (,) a <$> (arbitrary `suchThat` isClosedBy openElement)) $

From 208df10e1a16fef679b7e7688d8877e515ee5d08 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:02:34 -0500
Subject: [PATCH 208/259] Add an openMaybe function for quicker open/closed
 tests.

---
 test/SplitSpec.hs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 50c5a8756..4abf2eb47 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -122,3 +122,6 @@ spec = do
       leafWithRangesInSources sourceA sourceB rangeA rangeB = Free $ Annotated (Info rangeA mempty, Info rangeB mempty) (Leaf $ substring rangeA sourceA ++ substring rangeB sourceB)
 
       openString string = const string <$> openRange string (totalRange string)
+      openMaybe :: Maybe String -> Maybe (Maybe String)
+      openMaybe (Just a) = Just (Just a)
+      openMaybe Nothing =  Nothing

From 7b2ac7642217701050ef4ce707323ea420c5c342 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:05:02 -0500
Subject: [PATCH 209/259] Test not appending onto closed rows by means of
 openMaybe.

This is much faster.
---
 test/SplitSpec.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 4abf2eb47..6f63901c4 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -64,8 +64,8 @@ spec = do
           adjoinRowsBy openString openString [ a ] b `shouldBe` [ Row (Line $ a1 ++ a2) (Line $ b1 ++ b2) ]
 
     prop "does not append onto closed rows" $
-      forAll ((arbitrary `suchThat` isClosedBy openString) >>= \ a -> (,) a <$> (arbitrary `suchThat` isClosedBy openString)) $
-        \ (a, b) -> adjoinRowsBy openString openString [ a ] b `shouldBe` [ b, a ]
+      forAll ((arbitrary `suchThat` isClosedBy openMaybe) >>= \ a -> (,) a <$> (arbitrary `suchThat` isClosedBy openMaybe)) $
+        \ (a, b) -> adjoinRowsBy openMaybe openMaybe [ a ] b `shouldBe` [ b, a ]
 
     prop "does not promote elements through empty lines onto closed lines" $
       forAll ((arbitrary `suchThat` isClosedBy openElement) >>= \ a -> (,) a <$> (arbitrary `suchThat` isClosedBy openElement)) $

From 8f34f04dae58f465b2f9fa270df7c86fa7de1902 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:05:35 -0500
Subject: [PATCH 210/259] Test not promoting onto closed lines via openMaybe.

---
 test/SplitSpec.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 6f63901c4..f61ebf41d 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -68,8 +68,8 @@ spec = do
         \ (a, b) -> adjoinRowsBy openMaybe openMaybe [ a ] b `shouldBe` [ b, a ]
 
     prop "does not promote elements through empty lines onto closed lines" $
-      forAll ((arbitrary `suchThat` isClosedBy openElement) >>= \ a -> (,) a <$> (arbitrary `suchThat` isClosedBy openElement)) $
-        \ (a, b) -> adjoinRowsBy openElement openElement [ Row EmptyLine EmptyLine, a ] b `shouldBe` [ b, Row EmptyLine EmptyLine, a ]
+      forAll ((arbitrary `suchThat` isClosedBy openMaybe) >>= \ a -> (,) a <$> (arbitrary `suchThat` isClosedBy openMaybe)) $
+        \ (a, b) -> adjoinRowsBy openMaybe openMaybe [ Row EmptyLine EmptyLine, a ] b `shouldBe` [ b, Row EmptyLine EmptyLine, a ]
 
     prop "promotes elements through empty lines onto open lines" $
       forAll ((arbitrary `suchThat` isOpenBy openElement) >>= \ a -> (,) a <$> (arbitrary `suchThat` isOpenBy openElement)) $

From cfee3a90fcb0490c9a41a247abdbee24b662d149 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:06:09 -0500
Subject: [PATCH 211/259] Test promoting onto open lines via openMaybe.

---
 test/SplitSpec.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index f61ebf41d..e7ee94aad 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -72,8 +72,8 @@ spec = do
         \ (a, b) -> adjoinRowsBy openMaybe openMaybe [ Row EmptyLine EmptyLine, a ] b `shouldBe` [ b, Row EmptyLine EmptyLine, a ]
 
     prop "promotes elements through empty lines onto open lines" $
-      forAll ((arbitrary `suchThat` isOpenBy openElement) >>= \ a -> (,) a <$> (arbitrary `suchThat` isOpenBy openElement)) $
-        \ (a, b) -> adjoinRowsBy openElement openElement [ Row EmptyLine EmptyLine, a ] b `shouldBe` Row EmptyLine EmptyLine : adjoinRowsBy openElement openElement [ a ] b
+      forAll ((arbitrary `suchThat` isOpenBy openMaybe) >>= \ a -> (,) a <$> (arbitrary `suchThat` isOpenBy openMaybe)) $
+        \ (a, b) -> adjoinRowsBy openMaybe openMaybe [ Row EmptyLine EmptyLine, a ] b `shouldBe` Row EmptyLine EmptyLine : adjoinRowsBy openMaybe openMaybe [ a ] b
 
   describe "splitTermByLines" $ do
     prop "preserves line count" $

From cf00dcd95e7db761706d7e3f9f3266c6b4b0fdf3 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:06:45 -0500
Subject: [PATCH 212/259] Test appending onto open rows via openMaybe.

---
 test/SplitSpec.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index e7ee94aad..b17677c82 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -59,9 +59,9 @@ spec = do
       \ a -> adjoinRowsBy openString openString [] a == [ a ]
 
     prop "appends onto open rows" $
-      forAll ((arbitrary `suchThat` isOpenBy openString) >>= \ a -> (,) a <$> (arbitrary `suchThat` isOpenBy openString)) $
+      forAll ((arbitrary `suchThat` isOpenBy openMaybe) >>= \ a -> (,) a <$> (arbitrary `suchThat` isOpenBy openMaybe)) $
         \ (a@(Row (Line a1) (Line b1)), b@(Row (Line a2) (Line b2))) ->
-          adjoinRowsBy openString openString [ a ] b `shouldBe` [ Row (Line $ a1 ++ a2) (Line $ b1 ++ b2) ]
+          adjoinRowsBy openMaybe openMaybe [ a ] b `shouldBe` [ Row (Line $ a1 ++ a2) (Line $ b1 ++ b2) ]
 
     prop "does not append onto closed rows" $
       forAll ((arbitrary `suchThat` isClosedBy openMaybe) >>= \ a -> (,) a <$> (arbitrary `suchThat` isClosedBy openMaybe)) $

From 821ee2e79287c813253c51bd4ddc1f64159d860c Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:06:51 -0500
Subject: [PATCH 213/259] Test the identity case via openMaybe.

---
 test/SplitSpec.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index b17677c82..818d0a0fa 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -56,7 +56,7 @@ spec = do
 
   describe "adjoinRowsBy" $ do
     prop "is identity on top of no rows" $
-      \ a -> adjoinRowsBy openString openString [] a == [ a ]
+      \ a -> adjoinRowsBy openMaybe openMaybe [] a == [ a ]
 
     prop "appends onto open rows" $
       forAll ((arbitrary `suchThat` isOpenBy openMaybe) >>= \ a -> (,) a <$> (arbitrary `suchThat` isOpenBy openMaybe)) $

From b121ee54e336958abb353b605ae1f327355456ea Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:06:55 -0500
Subject: [PATCH 214/259] Remove openString.

---
 test/SplitSpec.hs | 1 -
 1 file changed, 1 deletion(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 818d0a0fa..9e180a4ac 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -121,7 +121,6 @@ spec = do
 
       leafWithRangesInSources sourceA sourceB rangeA rangeB = Free $ Annotated (Info rangeA mempty, Info rangeB mempty) (Leaf $ substring rangeA sourceA ++ substring rangeB sourceB)
 
-      openString string = const string <$> openRange string (totalRange string)
       openMaybe :: Maybe String -> Maybe (Maybe String)
       openMaybe (Just a) = Just (Just a)
       openMaybe Nothing =  Nothing

From 6663dfe87b3583e5f384f1976bf3ea18d45535af Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:08:02 -0500
Subject: [PATCH 215/259] openMaybe is defined over Maybe Bool.

---
 test/SplitSpec.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 9e180a4ac..843dedf29 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -121,6 +121,6 @@ spec = do
 
       leafWithRangesInSources sourceA sourceB rangeA rangeB = Free $ Annotated (Info rangeA mempty, Info rangeB mempty) (Leaf $ substring rangeA sourceA ++ substring rangeB sourceB)
 
-      openMaybe :: Maybe String -> Maybe (Maybe String)
+      openMaybe :: Maybe Bool -> Maybe (Maybe Bool)
       openMaybe (Just a) = Just (Just a)
       openMaybe Nothing =  Nothing

From 52a057b5773ad0d26bd1451adb19a3e98446d6ce Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:08:50 -0500
Subject: [PATCH 216/259] Remove the Arbitrary instance for HTML.

---
 test/SplitSpec.hs | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 843dedf29..eb0d345bd 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -18,12 +18,6 @@ instance Arbitrary a => Arbitrary (Row a) where
   arbitrary = oneof [
     Row <$> arbitrary <*> arbitrary ]
 
-instance Arbitrary HTML where
-  arbitrary = oneof [
-    Text <$> arbitrary,
-    Span <$> arbitrary <*> arbitrary,
-    const Break <$> (arbitrary :: Gen ()) ]
-
 instance Arbitrary a => Arbitrary (Line a) where
   arbitrary = oneof [
     Line <$> arbitrary,

From 6783d410bb5affd592336013078e01b3c97aa619 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:09:32 -0500
Subject: [PATCH 217/259] Remove `openElement`.

---
 src/Split.hs | 7 -------
 1 file changed, 7 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 9560a6312..9f9825b18 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -212,13 +212,6 @@ adjoinRowsBy _ g rows (Row left' right') | Just _ <- openLineBy g $ unRight <$>
 
 adjoinRowsBy _ _ rows row = row : rows
 
-openElement :: HTML -> Maybe HTML
-openElement Break = Nothing
-openElement (Ul _ elements) = openElement =<< maybeLast elements
-openElement (Dl _ elements) = openElement =<< maybeLast elements
-openElement (Div _ elements) = openElement =<< maybeLast elements
-openElement h = Just h
-
 openRange :: String -> Range -> Maybe Range
 openRange source range = case (source !!) <$> maybeLastIndex range of
   Just '\n' -> Nothing

From 3d1fb64cbc717c19128f904b32923b01c5d9abb4 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:10:49 -0500
Subject: [PATCH 218/259] Remove `span`.

---
 test/SplitSpec.hs | 1 -
 1 file changed, 1 deletion(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index eb0d345bd..019743f99 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -104,7 +104,6 @@ spec = do
       formatted source1 source2 category = Annotated (info source1 category, info source2 category)
       offsetInfo by (Info (Range start end) categories) = Info (Range (start + by) (end + by)) categories
       offsetAnnotated by1 by2 (Annotated (left, right) syntax) = Annotated (offsetInfo by1 left, offsetInfo by2 right) syntax
-      span = Span (Just "category-leaf")
       isOpenBy f (Row a b) = Maybe.isJust (openLineBy f [ a ]) && Maybe.isJust (openLineBy f [ b ])
       isClosedBy f (Row a@(Line _) b@(Line _)) = Maybe.isNothing (openLineBy f [ a ]) && Maybe.isNothing (openLineBy f [ b ])
       isClosedBy _ (Row _ _) = False

From ddf4ccd141bd79e0577fccee450e6fd523b66e63 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:10:57 -0500
Subject: [PATCH 219/259] Remove the row text functions.

---
 test/SplitSpec.hs | 5 -----
 1 file changed, 5 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 019743f99..17fefc6b4 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -94,11 +94,6 @@ spec = do
       openTerm " \n" (Info (Range 0 2) mempty :< Leaf "") `shouldBe` Nothing
 
     where
-      rightRowText text = rightRow [ Text text ]
-      rightRow xs = Row EmptyLine (Line xs)
-      leftRowText text = leftRow [ Text text ]
-      leftRow xs = Row (Line xs) EmptyLine
-      rowText a b = Row (Line [ Text a ]) (Line [ Text b ])
       info source category = Info (totalRange source)  (Set.fromList [ category ])
       unchanged source = formatted source source
       formatted source1 source2 category = Annotated (info source1 category, info source2 category)

From 08d03e933cd5c9c7923be49a5ad4eadba443d69f Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:11:49 -0500
Subject: [PATCH 220/259] Remove the term construction helpers.

---
 test/SplitSpec.hs | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 17fefc6b4..02ad4b73c 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -94,9 +94,6 @@ spec = do
       openTerm " \n" (Info (Range 0 2) mempty :< Leaf "") `shouldBe` Nothing
 
     where
-      info source category = Info (totalRange source)  (Set.fromList [ category ])
-      unchanged source = formatted source source
-      formatted source1 source2 category = Annotated (info source1 category, info source2 category)
       offsetInfo by (Info (Range start end) categories) = Info (Range (start + by) (end + by)) categories
       offsetAnnotated by1 by2 (Annotated (left, right) syntax) = Annotated (offsetInfo by1 left, offsetInfo by2 right) syntax
       isOpenBy f (Row a b) = Maybe.isJust (openLineBy f [ a ]) && Maybe.isJust (openLineBy f [ b ])

From 1621dca3bc70b85d5f48fa490ac7cad16cc444dd Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:12:08 -0500
Subject: [PATCH 221/259] Remove the offset functions.

---
 test/SplitSpec.hs | 2 --
 1 file changed, 2 deletions(-)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 02ad4b73c..cdfd8e424 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -94,8 +94,6 @@ spec = do
       openTerm " \n" (Info (Range 0 2) mempty :< Leaf "") `shouldBe` Nothing
 
     where
-      offsetInfo by (Info (Range start end) categories) = Info (Range (start + by) (end + by)) categories
-      offsetAnnotated by1 by2 (Annotated (left, right) syntax) = Annotated (offsetInfo by1 left, offsetInfo by2 right) syntax
       isOpenBy f (Row a b) = Maybe.isJust (openLineBy f [ a ]) && Maybe.isJust (openLineBy f [ b ])
       isClosedBy f (Row a@(Line _) b@(Line _)) = Maybe.isNothing (openLineBy f [ a ]) && Maybe.isNothing (openLineBy f [ b ])
       isClosedBy _ (Row _ _) = False

From e7196262168248ab2fe1564bf07fda44346d5f8c Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:12:56 -0500
Subject: [PATCH 222/259] Remove HTML.

---
 src/Split.hs | 10 ----------
 1 file changed, 10 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 9f9825b18..fb9de7f65 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -19,16 +19,6 @@ import Data.List (intercalate)
 
 type ClassName = String
 
-data HTML =
-  Break
-  | Text String
-  | Span (Maybe ClassName) String
-  | Ul (Maybe ClassName) [HTML]
-  | Dl (Maybe ClassName) [HTML]
-  | Div (Maybe ClassName) [HTML]
-  | Dt String
-  deriving (Show, Eq)
-
 classifyMarkup :: Maybe ClassName -> Markup -> Markup
 classifyMarkup (Just className) element = element ! A.class_ (stringValue className)
 classifyMarkup _ element = element

From 24d22042d10f1677b9ddb03bca2ad34a106d2ed0 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:18:17 -0500
Subject: [PATCH 223/259] `classifyMarkup` takes categories directly.

---
 src/Split.hs | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index fb9de7f65..190040b45 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -19,9 +19,8 @@ import Data.List (intercalate)
 
 type ClassName = String
 
-classifyMarkup :: Maybe ClassName -> Markup -> Markup
-classifyMarkup (Just className) element = element ! A.class_ (stringValue className)
-classifyMarkup _ element = element
+classifyMarkup :: Foldable f => f String -> Markup -> Markup
+classifyMarkup categories element = maybe element ((element !) . A.class_ . stringValue . ("category-" ++)) $ maybeLast categories
 
 split :: Diff a Info -> String -> String -> IO ByteString
 split diff before after = return . renderHtml
@@ -108,7 +107,7 @@ type SplitDiff leaf annotation = Free (Annotated leaf annotation) (Term leaf ann
 newtype Renderable a = Renderable (String, a)
 
 instance ToMarkup f => ToMarkup (Renderable (Info, Syntax a (f, Range))) where
-  toMarkup (Renderable (source, (Info range categories, syntax))) = classifyMarkup (classify categories) $ case syntax of
+  toMarkup (Renderable (source, (Info range categories, syntax))) = classifyMarkup categories $ case syntax of
     Leaf _ -> span . string $ substring range source
     Indexed children -> ul . mconcat $ contentElements children
     Fixed children -> ul . mconcat $ contentElements children

From ce2c759fea6e3786d96ea742408b5d62916b3d57 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:18:27 -0500
Subject: [PATCH 224/259] Remove `classify`.

---
 src/Split.hs | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 190040b45..6ebf5f81e 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -227,9 +227,6 @@ adjoinLinesBy _ lines line = line : lines
 zipWithDefaults :: (a -> b -> c) -> a -> b -> [a] -> [b] -> [c]
 zipWithDefaults f da db a b = take (max (length a) (length b)) $ zipWith f (a ++ repeat da) (b ++ repeat db)
 
-classify :: Set.Set Category -> Maybe ClassName
-classify categories = ("category-" ++) <$> maybeLast categories
-
 actualLines :: String -> [String]
 actualLines "" = [""]
 actualLines lines = case break (== '\n') lines of

From 8f469a07c4c089bbb4fd1dab0bd5ba4816ce1db9 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:20:08 -0500
Subject: [PATCH 225/259] Stub in a Line module.

---
 semantic-diff.cabal | 1 +
 src/Line.hs         | 1 +
 2 files changed, 2 insertions(+)
 create mode 100644 src/Line.hs

diff --git a/semantic-diff.cabal b/semantic-diff.cabal
index 1bd11f497..3d5f56637 100644
--- a/semantic-diff.cabal
+++ b/semantic-diff.cabal
@@ -18,6 +18,7 @@ library
                      , Operation
                      , Algorithm
                      , Interpreter
+                     , Line
                      , OrderedMap
                      , Patch
                      , SES
diff --git a/src/Line.hs b/src/Line.hs
new file mode 100644
index 000000000..3b9f94392
--- /dev/null
+++ b/src/Line.hs
@@ -0,0 +1 @@
+module Line where

From 4a39f65fdf2f10489263d9f348a7b7c3313470eb Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:21:17 -0500
Subject: [PATCH 226/259] Move Line to its own file.

---
 src/Line.hs  | 22 ++++++++++++++++++++++
 src/Split.hs | 21 +--------------------
 2 files changed, 23 insertions(+), 20 deletions(-)

diff --git a/src/Line.hs b/src/Line.hs
index 3b9f94392..5c416a94f 100644
--- a/src/Line.hs
+++ b/src/Line.hs
@@ -1 +1,23 @@
 module Line where
+
+import Data.Monoid
+import Data.List (intercalate)
+
+data Line a =
+  Line [a]
+  | EmptyLine
+  deriving (Eq, Functor)
+
+unLine :: Line a -> [a]
+unLine EmptyLine = []
+unLine (Line elements) = elements
+
+instance Show a => Show (Line a) where
+  show (Line elements) = "[" ++ intercalate ", " (show <$> elements) ++ "]"
+  show EmptyLine = "EmptyLine"
+
+instance Monoid (Line a) where
+  mempty = EmptyLine
+  mappend EmptyLine line = line
+  mappend line EmptyLine = line
+  mappend (Line xs) (Line ys) = Line (xs <> ys)
diff --git a/src/Split.hs b/src/Split.hs
index 6ebf5f81e..ddcdb9698 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -2,6 +2,7 @@ module Split where
 
 import Prelude hiding (div, head, span)
 import Diff
+import Line
 import Patch
 import Term
 import Syntax
@@ -15,7 +16,6 @@ import qualified Text.Blaze.Html5.Attributes as A
 import Text.Blaze.Html.Renderer.Utf8
 import Data.Monoid
 import qualified Data.Set as Set
-import Data.List (intercalate)
 
 type ClassName = String
 
@@ -82,25 +82,6 @@ instance ToMarkup a => ToMarkup (Line a) where
   toMarkup EmptyLine = codeTd False Nothing
   toMarkup (Line contents) = codeTd False . Just . mconcat $ toMarkup <$> contents
 
-data Line a =
-  Line [a]
-  | EmptyLine
-  deriving (Eq, Functor)
-
-unLine :: Line a -> [a]
-unLine EmptyLine = []
-unLine (Line elements) = elements
-
-instance Show a => Show (Line a) where
-  show (Line elements) = "[" ++ intercalate ", " (show <$> elements) ++ "]"
-  show EmptyLine = "EmptyLine"
-
-instance Monoid (Line a) where
-  mempty = EmptyLine
-  mappend EmptyLine line = line
-  mappend line EmptyLine = line
-  mappend (Line xs) (Line ys) = Line (xs <> ys)
-
 -- | A diff with only one side’s annotations.
 type SplitDiff leaf annotation = Free (Annotated leaf annotation) (Term leaf annotation)
 

From 4c395ff1d1a38409371fad356e060d073e464d96 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:22:07 -0500
Subject: [PATCH 227/259] Import the Line module in the tests.

---
 test/SplitSpec.hs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index cdfd8e424..286c01bb7 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -10,6 +10,7 @@ import Test.QuickCheck hiding (Fixed)
 import Control.Comonad.Cofree
 import Control.Monad.Free hiding (unfold)
 import qualified Data.Maybe as Maybe
+import Line
 import Patch
 import Syntax
 import ArbitraryTerm

From cdaea42fd2d2ef150540472c91c363b0e3244543 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:23:10 -0500
Subject: [PATCH 228/259] Move the ToMarkup instances over Line to the Line
 module.

---
 src/Line.hs  | 23 +++++++++++++++++++++++
 src/Split.hs | 21 ---------------------
 2 files changed, 23 insertions(+), 21 deletions(-)

diff --git a/src/Line.hs b/src/Line.hs
index 5c416a94f..ee546a155 100644
--- a/src/Line.hs
+++ b/src/Line.hs
@@ -2,6 +2,8 @@ module Line where
 
 import Data.Monoid
 import Data.List (intercalate)
+import Text.Blaze.Html5 hiding (map)
+import qualified Text.Blaze.Html5.Attributes as A
 
 data Line a =
   Line [a]
@@ -21,3 +23,24 @@ instance Monoid (Line a) where
   mappend EmptyLine line = line
   mappend line EmptyLine = line
   mappend (Line xs) (Line ys) = Line (xs <> ys)
+
+instance ToMarkup a => ToMarkup (Int, Line a, Int, Line a) where
+  toMarkup (m, left, n, right) = tr $ toMarkup (m, left) <> toMarkup (n, right) <> string "\n"
+
+instance ToMarkup a => ToMarkup (Int, Line a) where
+  toMarkup (_, line@EmptyLine) = numberTd "" <> toMarkup line <> string "\n"
+  -- toMarkup (num, line@(Line _)) = td (string $ show num) ! A.class_ (stringValue "blob-num blob-num-replacement") <> toMarkup line <> string "\n"
+  toMarkup (num, line@(Line _)) = numberTd (show num) <> toMarkup line <> string "\n"
+
+numberTd :: String -> Html
+numberTd "" = td mempty ! A.class_ (stringValue "blob-num blob-num-empty empty-cell")
+numberTd s = td (string s) ! A.class_ (stringValue "blob-num")
+
+codeTd :: Bool -> Maybe Html -> Html
+codeTd _ Nothing = td mempty ! A.class_ (stringValue "blob-code blob-code-empty empty-cell")
+codeTd True (Just el) = td el ! A.class_ (stringValue "blob-code blob-code-replacement")
+codeTd False (Just el) = td el ! A.class_ (stringValue "blob-code")
+
+instance ToMarkup a => ToMarkup (Line a) where
+  toMarkup EmptyLine = codeTd False Nothing
+  toMarkup (Line contents) = codeTd False . Just . mconcat $ toMarkup <$> contents
diff --git a/src/Split.hs b/src/Split.hs
index ddcdb9698..d927f1d2f 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -61,27 +61,6 @@ data Row a = Row { unLeft :: Line a, unRight :: Line a }
 instance Show a => Show (Row a) where
   show (Row left right) = "\n" ++ show left ++ " | " ++ show right
 
-instance ToMarkup a => ToMarkup (Int, Line a, Int, Line a) where
-  toMarkup (m, left, n, right) = tr $ toMarkup (m, left) <> toMarkup (n, right) <> string "\n"
-
-instance ToMarkup a => ToMarkup (Int, Line a) where
-  toMarkup (_, line@EmptyLine) = numberTd "" <> toMarkup line <> string "\n"
-  -- toMarkup (num, line@(Line _)) = td (string $ show num) ! A.class_ (stringValue "blob-num blob-num-replacement") <> toMarkup line <> string "\n"
-  toMarkup (num, line@(Line _)) = numberTd (show num) <> toMarkup line <> string "\n"
-
-numberTd :: String -> Html
-numberTd "" = td mempty ! A.class_ (stringValue "blob-num blob-num-empty empty-cell")
-numberTd s = td (string s) ! A.class_ (stringValue "blob-num")
-
-codeTd :: Bool -> Maybe Html -> Html
-codeTd _ Nothing = td mempty ! A.class_ (stringValue "blob-code blob-code-empty empty-cell")
-codeTd True (Just el) = td el ! A.class_ (stringValue "blob-code blob-code-replacement")
-codeTd False (Just el) = td el ! A.class_ (stringValue "blob-code")
-
-instance ToMarkup a => ToMarkup (Line a) where
-  toMarkup EmptyLine = codeTd False Nothing
-  toMarkup (Line contents) = codeTd False . Just . mconcat $ toMarkup <$> contents
-
 -- | A diff with only one side’s annotations.
 type SplitDiff leaf annotation = Free (Annotated leaf annotation) (Term leaf annotation)
 

From b256d46f836e467c0cacd1a9b6b08b64b9553a5c Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:24:08 -0500
Subject: [PATCH 229/259] Stub in a Row module.

---
 semantic-diff.cabal | 1 +
 src/Row.hs          | 1 +
 2 files changed, 2 insertions(+)
 create mode 100644 src/Row.hs

diff --git a/semantic-diff.cabal b/semantic-diff.cabal
index 3d5f56637..156bd94d8 100644
--- a/semantic-diff.cabal
+++ b/semantic-diff.cabal
@@ -19,6 +19,7 @@ library
                      , Algorithm
                      , Interpreter
                      , Line
+                     , Row
                      , OrderedMap
                      , Patch
                      , SES
diff --git a/src/Row.hs b/src/Row.hs
new file mode 100644
index 000000000..c1e73784f
--- /dev/null
+++ b/src/Row.hs
@@ -0,0 +1 @@
+module Row where

From e2cc92bdf7be2d604e48d65edf3336c82c6771e8 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:24:58 -0500
Subject: [PATCH 230/259] Move Row into the Row module.

---
 src/Row.hs        | 8 ++++++++
 src/Split.hs      | 8 +-------
 test/SplitSpec.hs | 1 +
 3 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/src/Row.hs b/src/Row.hs
index c1e73784f..52b6982f3 100644
--- a/src/Row.hs
+++ b/src/Row.hs
@@ -1 +1,9 @@
 module Row where
+
+import Line
+
+data Row a = Row { unLeft :: Line a, unRight :: Line a }
+  deriving (Eq, Functor)
+
+instance Show a => Show (Row a) where
+  show (Row left right) = "\n" ++ show left ++ " | " ++ show right
diff --git a/src/Split.hs b/src/Split.hs
index d927f1d2f..80adf34c9 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -3,6 +3,7 @@ module Split where
 import Prelude hiding (div, head, span)
 import Diff
 import Line
+import Row
 import Patch
 import Term
 import Syntax
@@ -54,13 +55,6 @@ split diff before after = return . renderHtml
     numberRows rows@((leftCount, _, rightCount, _):_) (Row EmptyLine right@(Line _)) = (leftCount, EmptyLine, rightCount + 1, right):rows
     numberRows rows@((leftCount, _, rightCount, _):_) (Row left right) = (leftCount + 1, left, rightCount + 1, right):rows
 
-
-data Row a = Row { unLeft :: Line a, unRight :: Line a }
-  deriving (Eq, Functor)
-
-instance Show a => Show (Row a) where
-  show (Row left right) = "\n" ++ show left ++ " | " ++ show right
-
 -- | A diff with only one side’s annotations.
 type SplitDiff leaf annotation = Free (Annotated leaf annotation) (Term leaf annotation)
 
diff --git a/test/SplitSpec.hs b/test/SplitSpec.hs
index 286c01bb7..da8b89344 100644
--- a/test/SplitSpec.hs
+++ b/test/SplitSpec.hs
@@ -11,6 +11,7 @@ import Control.Comonad.Cofree
 import Control.Monad.Free hiding (unfold)
 import qualified Data.Maybe as Maybe
 import Line
+import Row
 import Patch
 import Syntax
 import ArbitraryTerm

From 74fbc6e5395e50213335e9b5b6715e291ea8a7d4 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:26:24 -0500
Subject: [PATCH 231/259] Move openLineBy into the Line module.

---
 src/Line.hs  | 8 ++++++++
 src/Split.hs | 8 --------
 2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/src/Line.hs b/src/Line.hs
index ee546a155..4f5c84c27 100644
--- a/src/Line.hs
+++ b/src/Line.hs
@@ -14,6 +14,14 @@ unLine :: Line a -> [a]
 unLine EmptyLine = []
 unLine (Line elements) = elements
 
+maybeLast :: Foldable f => f a -> Maybe a
+maybeLast = foldl (flip $ const . Just) Nothing
+
+openLineBy :: (a -> Maybe a) -> [Line a] -> Maybe (Line a)
+openLineBy _ [] = Nothing
+openLineBy f (EmptyLine : rest) = openLineBy f rest
+openLineBy f (line : _) = const line <$> (f =<< maybeLast (unLine line))
+
 instance Show a => Show (Line a) where
   show (Line elements) = "[" ++ intercalate ", " (show <$> elements) ++ "]"
   show EmptyLine = "EmptyLine"
diff --git a/src/Split.hs b/src/Split.hs
index 80adf34c9..d826dccdd 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -129,9 +129,6 @@ splitAnnotatedByLines sources ranges categories syntax = case syntax of
 contextLines :: (Info -> a) -> Range -> Set.Set Category -> String -> [Line a]
 contextLines constructor range categories source = Line . (:[]) . constructor . (`Info` categories) <$> actualLineRanges range source
 
-maybeLast :: Foldable f => f a -> Maybe a
-maybeLast = foldl (flip $ const . Just) Nothing
-
 adjoinRowsBy :: (a -> Maybe a) -> (a -> Maybe a) -> [Row a] -> Row a -> [Row a]
 adjoinRowsBy _ _ [] row = [row]
 
@@ -167,11 +164,6 @@ openDiff :: String -> SplitDiff a Info -> Maybe (SplitDiff a Info)
 openDiff source diff@(Free (Annotated (Info range _) _)) = const diff <$> openRange source range
 openDiff source diff@(Pure term) = const diff <$> openTerm source term
 
-openLineBy :: (a -> Maybe a) -> [Line a] -> Maybe (Line a)
-openLineBy _ [] = Nothing
-openLineBy f (EmptyLine : rest) = openLineBy f rest
-openLineBy f (line : _) = const line <$> (f =<< maybeLast (unLine line))
-
 adjoinLinesBy :: (a -> Maybe a) -> [Line a] -> Line a -> [Line a]
 adjoinLinesBy _ [] line = [line]
 adjoinLinesBy f (EmptyLine : xs) line | Just _ <- openLineBy f xs = EmptyLine : adjoinLinesBy f xs line

From c92ba49b4d4a4e963928cc2facd42aa82fc0485c Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:27:09 -0500
Subject: [PATCH 232/259] Move adjoinLinesBy into the Line module.

---
 src/Line.hs  | 6 ++++++
 src/Split.hs | 6 ------
 2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/src/Line.hs b/src/Line.hs
index 4f5c84c27..945536e40 100644
--- a/src/Line.hs
+++ b/src/Line.hs
@@ -22,6 +22,12 @@ openLineBy _ [] = Nothing
 openLineBy f (EmptyLine : rest) = openLineBy f rest
 openLineBy f (line : _) = const line <$> (f =<< maybeLast (unLine line))
 
+adjoinLinesBy :: (a -> Maybe a) -> [Line a] -> Line a -> [Line a]
+adjoinLinesBy _ [] line = [line]
+adjoinLinesBy f (EmptyLine : xs) line | Just _ <- openLineBy f xs = EmptyLine : adjoinLinesBy f xs line
+adjoinLinesBy f (prev:rest) line | Just _ <- openLineBy f [ prev ] = (prev <> line) : rest
+adjoinLinesBy _ lines line = line : lines
+
 instance Show a => Show (Line a) where
   show (Line elements) = "[" ++ intercalate ", " (show <$> elements) ++ "]"
   show EmptyLine = "EmptyLine"
diff --git a/src/Split.hs b/src/Split.hs
index d826dccdd..4d5c19a1f 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -164,12 +164,6 @@ openDiff :: String -> SplitDiff a Info -> Maybe (SplitDiff a Info)
 openDiff source diff@(Free (Annotated (Info range _) _)) = const diff <$> openRange source range
 openDiff source diff@(Pure term) = const diff <$> openTerm source term
 
-adjoinLinesBy :: (a -> Maybe a) -> [Line a] -> Line a -> [Line a]
-adjoinLinesBy _ [] line = [line]
-adjoinLinesBy f (EmptyLine : xs) line | Just _ <- openLineBy f xs = EmptyLine : adjoinLinesBy f xs line
-adjoinLinesBy f (prev:rest) line | Just _ <- openLineBy f [ prev ] = (prev <> line) : rest
-adjoinLinesBy _ lines line = line : lines
-
 zipWithDefaults :: (a -> b -> c) -> a -> b -> [a] -> [b] -> [c]
 zipWithDefaults f da db a b = take (max (length a) (length b)) $ zipWith f (a ++ repeat da) (b ++ repeat db)
 

From b1659945697c447e8f0f56a54cae60252d02ef1d Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:27:56 -0500
Subject: [PATCH 233/259] Move adjoinRowsBy into the Row module.

---
 src/Row.hs   | 24 ++++++++++++++++++++++++
 src/Split.hs | 23 -----------------------
 2 files changed, 24 insertions(+), 23 deletions(-)

diff --git a/src/Row.hs b/src/Row.hs
index 52b6982f3..4fbbaa121 100644
--- a/src/Row.hs
+++ b/src/Row.hs
@@ -5,5 +5,29 @@ import Line
 data Row a = Row { unLeft :: Line a, unRight :: Line a }
   deriving (Eq, Functor)
 
+adjoinRowsBy :: (a -> Maybe a) -> (a -> Maybe a) -> [Row a] -> Row a -> [Row a]
+adjoinRowsBy _ _ [] row = [row]
+
+adjoinRowsBy f g rows (Row left' right') | Just _ <- openLineBy f $ unLeft <$> rows, Just _ <- openLineBy g $ unRight <$> rows = zipWith Row lefts rights
+  where lefts = adjoinLinesBy f (unLeft <$> rows) left'
+        rights = adjoinLinesBy g (unRight <$> rows) right'
+
+adjoinRowsBy f _ rows (Row left' right') | Just _ <- openLineBy f $ unLeft <$> rows = case right' of
+  EmptyLine -> rest
+  _ -> Row EmptyLine right' : rest
+  where rest = zipWith Row lefts rights
+        lefts = adjoinLinesBy f (unLeft <$> rows) left'
+        rights = unRight <$> rows
+
+adjoinRowsBy _ g rows (Row left' right') | Just _ <- openLineBy g $ unRight <$> rows = case left' of
+  EmptyLine -> rest
+  _ -> Row left' EmptyLine : rest
+  where rest = zipWith Row lefts rights
+        lefts = unLeft <$> rows
+        rights = adjoinLinesBy g (unRight <$> rows) right'
+
+adjoinRowsBy _ _ rows row = row : rows
+
+
 instance Show a => Show (Row a) where
   show (Row left right) = "\n" ++ show left ++ " | " ++ show right
diff --git a/src/Split.hs b/src/Split.hs
index 4d5c19a1f..73e7722f5 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -129,29 +129,6 @@ splitAnnotatedByLines sources ranges categories syntax = case syntax of
 contextLines :: (Info -> a) -> Range -> Set.Set Category -> String -> [Line a]
 contextLines constructor range categories source = Line . (:[]) . constructor . (`Info` categories) <$> actualLineRanges range source
 
-adjoinRowsBy :: (a -> Maybe a) -> (a -> Maybe a) -> [Row a] -> Row a -> [Row a]
-adjoinRowsBy _ _ [] row = [row]
-
-adjoinRowsBy f g rows (Row left' right') | Just _ <- openLineBy f $ unLeft <$> rows, Just _ <- openLineBy g $ unRight <$> rows = zipWith Row lefts rights
-  where lefts = adjoinLinesBy f (unLeft <$> rows) left'
-        rights = adjoinLinesBy g (unRight <$> rows) right'
-
-adjoinRowsBy f _ rows (Row left' right') | Just _ <- openLineBy f $ unLeft <$> rows = case right' of
-  EmptyLine -> rest
-  _ -> Row EmptyLine right' : rest
-  where rest = zipWith Row lefts rights
-        lefts = adjoinLinesBy f (unLeft <$> rows) left'
-        rights = unRight <$> rows
-
-adjoinRowsBy _ g rows (Row left' right') | Just _ <- openLineBy g $ unRight <$> rows = case left' of
-  EmptyLine -> rest
-  _ -> Row left' EmptyLine : rest
-  where rest = zipWith Row lefts rights
-        lefts = unLeft <$> rows
-        rights = adjoinLinesBy g (unRight <$> rows) right'
-
-adjoinRowsBy _ _ rows row = row : rows
-
 openRange :: String -> Range -> Maybe Range
 openRange source range = case (source !!) <$> maybeLastIndex range of
   Just '\n' -> Nothing

From 7e98ee3de59b99258937a552e2244e6082452e13 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:53:47 -0500
Subject: [PATCH 234/259] Add a function to map a line into a Renderable line.

---
 src/Split.hs | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index 73e7722f5..ba7ab5a43 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -33,7 +33,7 @@ split diff before after = return . renderHtml
         . mconcat $ toMarkup <$> reverse numbered
   where
     rows = toRenderable <$> fst (splitDiffByLines diff (0, 0) (before, after))
-    toRenderable (Row a b) = Row (Renderable . (,) before <$> a) (Renderable . (,) after <$> b)
+    toRenderable (Row a b) = Row (renderable before a) (renderable after b)
     numbered = foldl numberRows [] rows
     maxNumber = case numbered of
       [] -> 0
@@ -45,6 +45,8 @@ split diff before after = return . renderHtml
 
     columnWidth = max (20 + digits maxNumber * 8) 40
 
+    renderable source = fmap (Renderable . (,) source)
+
     numberRows :: [(Int, Line a, Int, Line a)] -> Row a -> [(Int, Line a, Int, Line a)]
     numberRows [] (Row EmptyLine EmptyLine) = []
     numberRows [] (Row left@(Line _) EmptyLine) = [(1, left, 0, EmptyLine)]

From e9c7c46130d2b493b8d4ef6f0925abd3e8d2d1e8 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:54:01 -0500
Subject: [PATCH 235/259] Add a function to test for changes in a diff.

---
 src/Split.hs | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/Split.hs b/src/Split.hs
index ba7ab5a43..9b469dcbd 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -47,6 +47,8 @@ split diff before after = return . renderHtml
 
     renderable source = fmap (Renderable . (,) source)
 
+    hasChanges diff = foldl (||) False $ const True <$> diff
+
     numberRows :: [(Int, Line a, Int, Line a)] -> Row a -> [(Int, Line a, Int, Line a)]
     numberRows [] (Row EmptyLine EmptyLine) = []
     numberRows [] (Row left@(Line _) EmptyLine) = [(1, left, 0, EmptyLine)]

From b89218a94476433f1b126ec47213ed33c21d53bf Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:55:03 -0500
Subject: [PATCH 236/259] Add a ToMarkup instance over Bool/Int/Line a triples.

---
 src/Line.hs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/Line.hs b/src/Line.hs
index 945536e40..88b72b4d8 100644
--- a/src/Line.hs
+++ b/src/Line.hs
@@ -45,6 +45,10 @@ instance ToMarkup a => ToMarkup (Int, Line a) where
   toMarkup (_, line@EmptyLine) = numberTd "" <> toMarkup line <> string "\n"
   -- toMarkup (num, line@(Line _)) = td (string $ show num) ! A.class_ (stringValue "blob-num blob-num-replacement") <> toMarkup line <> string "\n"
   toMarkup (num, line@(Line _)) = numberTd (show num) <> toMarkup line <> string "\n"
+instance ToMarkup a => ToMarkup (Bool, Int, Line a) where
+  toMarkup (_, _, line@EmptyLine) = numberTd "" <> toMarkup line <> string "\n"
+  toMarkup (True, num, line@(Line _)) = td (string $ show num) ! A.class_ (stringValue "blob-num blob-num-replacement") <> toMarkup line <> string "\n"
+  toMarkup (_, num, line@(Line _)) = numberTd (show num) <> toMarkup line <> string "\n"
 
 numberTd :: String -> Html
 numberTd "" = td mempty ! A.class_ (stringValue "blob-num blob-num-empty empty-cell")

From e974ea43af09dc185044bc163622f1e6d045c019 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:55:30 -0500
Subject: [PATCH 237/259] Add a function to render numbered lines to markup
 with indication of changes.

---
 src/Split.hs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/Split.hs b/src/Split.hs
index 9b469dcbd..87b9311bf 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -45,6 +45,9 @@ split diff before after = return . renderHtml
 
     columnWidth = max (20 + digits maxNumber * 8) 40
 
+    numberedLinesToMarkup :: (Int, Line (SplitDiff a Info), Int, Line (SplitDiff a Info)) -> Markup
+    numberedLinesToMarkup (m, left, n, right) = tr $ toMarkup (foldl (||) False $ hasChanges <$> unLine left, m, renderable before left) <> toMarkup (foldl (||) False $ hasChanges <$> unLine right, n, renderable after right) <> string "\n"
+
     renderable source = fmap (Renderable . (,) source)
 
     hasChanges diff = foldl (||) False $ const True <$> diff

From 44e04ec17f739cb30edc4bf857afc5e163431aa8 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:55:54 -0500
Subject: [PATCH 238/259] Render numbered lines to markup using the new
 function.

---
 src/Split.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 87b9311bf..c07108baf 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -30,9 +30,9 @@ split diff before after = return . renderHtml
     . body
       . (table ! A.class_ (stringValue "diff")) $
         ((colgroup $ (col ! A.width (stringValue . show $ columnWidth)) <> col <> (col ! A.width (stringValue . show $ columnWidth)) <> col) <>)
-        . mconcat $ toMarkup <$> reverse numbered
+        . mconcat $ numberedLinesToMarkup <$> reverse numbered
   where
-    rows = toRenderable <$> fst (splitDiffByLines diff (0, 0) (before, after))
+    rows = fst (splitDiffByLines diff (0, 0) (before, after))
     toRenderable (Row a b) = Row (renderable before a) (renderable after b)
     numbered = foldl numberRows [] rows
     maxNumber = case numbered of

From 02afbd132a03a7c6f937097f69dc5f753ebc0d91 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:56:10 -0500
Subject: [PATCH 239/259] Remove the Int, Line, Int, Line instance of ToMarkup.

---
 src/Line.hs | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/src/Line.hs b/src/Line.hs
index 88b72b4d8..f933aa303 100644
--- a/src/Line.hs
+++ b/src/Line.hs
@@ -38,9 +38,6 @@ instance Monoid (Line a) where
   mappend line EmptyLine = line
   mappend (Line xs) (Line ys) = Line (xs <> ys)
 
-instance ToMarkup a => ToMarkup (Int, Line a, Int, Line a) where
-  toMarkup (m, left, n, right) = tr $ toMarkup (m, left) <> toMarkup (n, right) <> string "\n"
-
 instance ToMarkup a => ToMarkup (Int, Line a) where
   toMarkup (_, line@EmptyLine) = numberTd "" <> toMarkup line <> string "\n"
   -- toMarkup (num, line@(Line _)) = td (string $ show num) ! A.class_ (stringValue "blob-num blob-num-replacement") <> toMarkup line <> string "\n"

From c83c67cc9932d04a6c8c2337c21ce7e92f121576 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:56:19 -0500
Subject: [PATCH 240/259] Remove the Int, Line pair instance of ToMarkup.

---
 src/Line.hs | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/src/Line.hs b/src/Line.hs
index f933aa303..dbf1359ad 100644
--- a/src/Line.hs
+++ b/src/Line.hs
@@ -38,10 +38,6 @@ instance Monoid (Line a) where
   mappend line EmptyLine = line
   mappend (Line xs) (Line ys) = Line (xs <> ys)
 
-instance ToMarkup a => ToMarkup (Int, Line a) where
-  toMarkup (_, line@EmptyLine) = numberTd "" <> toMarkup line <> string "\n"
-  -- toMarkup (num, line@(Line _)) = td (string $ show num) ! A.class_ (stringValue "blob-num blob-num-replacement") <> toMarkup line <> string "\n"
-  toMarkup (num, line@(Line _)) = numberTd (show num) <> toMarkup line <> string "\n"
 instance ToMarkup a => ToMarkup (Bool, Int, Line a) where
   toMarkup (_, _, line@EmptyLine) = numberTd "" <> toMarkup line <> string "\n"
   toMarkup (True, num, line@(Line _)) = td (string $ show num) ! A.class_ (stringValue "blob-num blob-num-replacement") <> toMarkup line <> string "\n"

From b25da81f81d233ef9d623de4934414329550a93a Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:56:28 -0500
Subject: [PATCH 241/259] Remove toRenderable.

---
 src/Split.hs | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index c07108baf..751576a2e 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -33,7 +33,6 @@ split diff before after = return . renderHtml
         . mconcat $ numberedLinesToMarkup <$> reverse numbered
   where
     rows = fst (splitDiffByLines diff (0, 0) (before, after))
-    toRenderable (Row a b) = Row (renderable before a) (renderable after b)
     numbered = foldl numberRows [] rows
     maxNumber = case numbered of
       [] -> 0

From 946b1067b3478a7298afb14b1fb8296b31644c8b Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:57:16 -0500
Subject: [PATCH 242/259] Use `or` to test for changes.

---
 src/Split.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/Split.hs b/src/Split.hs
index 751576a2e..6a06d27ba 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -45,11 +45,11 @@ split diff before after = return . renderHtml
     columnWidth = max (20 + digits maxNumber * 8) 40
 
     numberedLinesToMarkup :: (Int, Line (SplitDiff a Info), Int, Line (SplitDiff a Info)) -> Markup
-    numberedLinesToMarkup (m, left, n, right) = tr $ toMarkup (foldl (||) False $ hasChanges <$> unLine left, m, renderable before left) <> toMarkup (foldl (||) False $ hasChanges <$> unLine right, n, renderable after right) <> string "\n"
+    numberedLinesToMarkup (m, left, n, right) = tr $ toMarkup (or $ hasChanges <$> unLine left, m, renderable before left) <> toMarkup (or $ hasChanges <$> unLine right, n, renderable after right) <> string "\n"
 
     renderable source = fmap (Renderable . (,) source)
 
-    hasChanges diff = foldl (||) False $ const True <$> diff
+    hasChanges diff = or $ const True <$> diff
 
     numberRows :: [(Int, Line a, Int, Line a)] -> Row a -> [(Int, Line a, Int, Line a)]
     numberRows [] (Row EmptyLine EmptyLine) = []

From cd5abba7435ed46a04c6b42fc077c7b9527753b4 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:58:11 -0500
Subject: [PATCH 243/259] Derive a Foldable instance for Line.

---
 src/Line.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Line.hs b/src/Line.hs
index dbf1359ad..e33c13e90 100644
--- a/src/Line.hs
+++ b/src/Line.hs
@@ -8,7 +8,7 @@ import qualified Text.Blaze.Html5.Attributes as A
 data Line a =
   Line [a]
   | EmptyLine
-  deriving (Eq, Functor)
+  deriving (Eq, Functor, Foldable)
 
 unLine :: Line a -> [a]
 unLine EmptyLine = []

From 9b87a785b5ffdd71b9330854ef34a047a989c44b Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 17:59:26 -0500
Subject: [PATCH 244/259] No need to unLine.

---
 src/Split.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Split.hs b/src/Split.hs
index 6a06d27ba..4580fd0ea 100644
--- a/src/Split.hs
+++ b/src/Split.hs
@@ -45,7 +45,7 @@ split diff before after = return . renderHtml
     columnWidth = max (20 + digits maxNumber * 8) 40
 
     numberedLinesToMarkup :: (Int, Line (SplitDiff a Info), Int, Line (SplitDiff a Info)) -> Markup
-    numberedLinesToMarkup (m, left, n, right) = tr $ toMarkup (or $ hasChanges <$> unLine left, m, renderable before left) <> toMarkup (or $ hasChanges <$> unLine right, n, renderable after right) <> string "\n"
+    numberedLinesToMarkup (m, left, n, right) = tr $ toMarkup (or $ hasChanges <$> left, m, renderable before left) <> toMarkup (or $ hasChanges <$> right, n, renderable after right) <> string "\n"
 
     renderable source = fmap (Renderable . (,) source)
 

From 6c6139aac90502f85bbd0724a1996c18dac72da0 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 18:06:42 -0500
Subject: [PATCH 245/259] =?UTF-8?q?Don=E2=80=99t=20depend=20on=20numberTd.?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 src/Line.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/Line.hs b/src/Line.hs
index e33c13e90..5e86cd09f 100644
--- a/src/Line.hs
+++ b/src/Line.hs
@@ -39,9 +39,9 @@ instance Monoid (Line a) where
   mappend (Line xs) (Line ys) = Line (xs <> ys)
 
 instance ToMarkup a => ToMarkup (Bool, Int, Line a) where
-  toMarkup (_, _, line@EmptyLine) = numberTd "" <> toMarkup line <> string "\n"
+  toMarkup (_, _, line@EmptyLine) = td mempty ! A.class_ (stringValue "blob-num blob-num-empty empty-cell") <> toMarkup line <> string "\n"
   toMarkup (True, num, line@(Line _)) = td (string $ show num) ! A.class_ (stringValue "blob-num blob-num-replacement") <> toMarkup line <> string "\n"
-  toMarkup (_, num, line@(Line _)) = numberTd (show num) <> toMarkup line <> string "\n"
+  toMarkup (_, num, line@(Line _)) = td (string $ show num) ! A.class_ (stringValue "blob-num") <> toMarkup line <> string "\n"
 
 numberTd :: String -> Html
 numberTd "" = td mempty ! A.class_ (stringValue "blob-num blob-num-empty empty-cell")

From de1482af2c589071f236eccf636a397d5ed7275f Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 18:06:49 -0500
Subject: [PATCH 246/259] Remove numberTd.

---
 src/Line.hs | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/src/Line.hs b/src/Line.hs
index 5e86cd09f..cff4c2fb6 100644
--- a/src/Line.hs
+++ b/src/Line.hs
@@ -43,10 +43,6 @@ instance ToMarkup a => ToMarkup (Bool, Int, Line a) where
   toMarkup (True, num, line@(Line _)) = td (string $ show num) ! A.class_ (stringValue "blob-num blob-num-replacement") <> toMarkup line <> string "\n"
   toMarkup (_, num, line@(Line _)) = td (string $ show num) ! A.class_ (stringValue "blob-num") <> toMarkup line <> string "\n"
 
-numberTd :: String -> Html
-numberTd "" = td mempty ! A.class_ (stringValue "blob-num blob-num-empty empty-cell")
-numberTd s = td (string s) ! A.class_ (stringValue "blob-num")
-
 codeTd :: Bool -> Maybe Html -> Html
 codeTd _ Nothing = td mempty ! A.class_ (stringValue "blob-code blob-code-empty empty-cell")
 codeTd True (Just el) = td el ! A.class_ (stringValue "blob-code blob-code-replacement")

From cfe2cd336e49db8a530bffcab45da44f7bf504b1 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 18:13:43 -0500
Subject: [PATCH 247/259] Define toMarkup over Bool/Int/Line triples by pattern
 matching.

---
 src/Line.hs | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/Line.hs b/src/Line.hs
index cff4c2fb6..21a2f61d9 100644
--- a/src/Line.hs
+++ b/src/Line.hs
@@ -39,6 +39,11 @@ instance Monoid (Line a) where
   mappend (Line xs) (Line ys) = Line (xs <> ys)
 
 instance ToMarkup a => ToMarkup (Bool, Int, Line a) where
+  toMarkup (hasChanges, num, line) = case line of
+    EmptyLine -> td mempty ! A.class_ (stringValue "blob-num blob-num-empty empty-cell") <> td mempty ! A.class_ (stringValue "blob-code blob-code-empty empty-cell") <> string "\n"
+    _ -> cell "num" (string $ show num) <> cell "code" (toMarkup line) <> string "\n"
+    where cell kind = td ! A.class_ (toClass kind)
+          toClass kind = stringValue $ "blob-" ++ kind ++ if hasChanges then " blob-" ++ kind ++ "-replacement" else ""
   toMarkup (_, _, line@EmptyLine) = td mempty ! A.class_ (stringValue "blob-num blob-num-empty empty-cell") <> toMarkup line <> string "\n"
   toMarkup (True, num, line@(Line _)) = td (string $ show num) ! A.class_ (stringValue "blob-num blob-num-replacement") <> toMarkup line <> string "\n"
   toMarkup (_, num, line@(Line _)) = td (string $ show num) ! A.class_ (stringValue "blob-num") <> toMarkup line <> string "\n"

From fbda7e11c1025a1ae01073fcf6a08d54a2694635 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 18:14:01 -0500
Subject: [PATCH 248/259] Remove the old definitions.

---
 src/Line.hs | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/src/Line.hs b/src/Line.hs
index 21a2f61d9..9b1a3133e 100644
--- a/src/Line.hs
+++ b/src/Line.hs
@@ -44,9 +44,6 @@ instance ToMarkup a => ToMarkup (Bool, Int, Line a) where
     _ -> cell "num" (string $ show num) <> cell "code" (toMarkup line) <> string "\n"
     where cell kind = td ! A.class_ (toClass kind)
           toClass kind = stringValue $ "blob-" ++ kind ++ if hasChanges then " blob-" ++ kind ++ "-replacement" else ""
-  toMarkup (_, _, line@EmptyLine) = td mempty ! A.class_ (stringValue "blob-num blob-num-empty empty-cell") <> toMarkup line <> string "\n"
-  toMarkup (True, num, line@(Line _)) = td (string $ show num) ! A.class_ (stringValue "blob-num blob-num-replacement") <> toMarkup line <> string "\n"
-  toMarkup (_, num, line@(Line _)) = td (string $ show num) ! A.class_ (stringValue "blob-num") <> toMarkup line <> string "\n"
 
 codeTd :: Bool -> Maybe Html -> Html
 codeTd _ Nothing = td mempty ! A.class_ (stringValue "blob-code blob-code-empty empty-cell")

From 30c281c185b2c3fc58da4f8845a3875bcb0e2abc Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 18:14:36 -0500
Subject: [PATCH 249/259] Inline the cell class.

---
 src/Line.hs | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/src/Line.hs b/src/Line.hs
index 9b1a3133e..165cb6fab 100644
--- a/src/Line.hs
+++ b/src/Line.hs
@@ -42,8 +42,7 @@ instance ToMarkup a => ToMarkup (Bool, Int, Line a) where
   toMarkup (hasChanges, num, line) = case line of
     EmptyLine -> td mempty ! A.class_ (stringValue "blob-num blob-num-empty empty-cell") <> td mempty ! A.class_ (stringValue "blob-code blob-code-empty empty-cell") <> string "\n"
     _ -> cell "num" (string $ show num) <> cell "code" (toMarkup line) <> string "\n"
-    where cell kind = td ! A.class_ (toClass kind)
-          toClass kind = stringValue $ "blob-" ++ kind ++ if hasChanges then " blob-" ++ kind ++ "-replacement" else ""
+    where cell kind = td ! A.class_ (stringValue $ "blob-" ++ kind ++ if hasChanges then " blob-" ++ kind ++ "-replacement" else "")
 
 codeTd :: Bool -> Maybe Html -> Html
 codeTd _ Nothing = td mempty ! A.class_ (stringValue "blob-code blob-code-empty empty-cell")

From 1241cbeff9db2628dfc33251176b793ca7dfaa96 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 18:18:10 -0500
Subject: [PATCH 250/259] Revert "Inline the cell class."

This reverts commit 2e484d1dbd3c694165bdcff6a32486256d93041e.
---
 src/Line.hs | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/Line.hs b/src/Line.hs
index 165cb6fab..9b1a3133e 100644
--- a/src/Line.hs
+++ b/src/Line.hs
@@ -42,7 +42,8 @@ instance ToMarkup a => ToMarkup (Bool, Int, Line a) where
   toMarkup (hasChanges, num, line) = case line of
     EmptyLine -> td mempty ! A.class_ (stringValue "blob-num blob-num-empty empty-cell") <> td mempty ! A.class_ (stringValue "blob-code blob-code-empty empty-cell") <> string "\n"
     _ -> cell "num" (string $ show num) <> cell "code" (toMarkup line) <> string "\n"
-    where cell kind = td ! A.class_ (stringValue $ "blob-" ++ kind ++ if hasChanges then " blob-" ++ kind ++ "-replacement" else "")
+    where cell kind = td ! A.class_ (toClass kind)
+          toClass kind = stringValue $ "blob-" ++ kind ++ if hasChanges then " blob-" ++ kind ++ "-replacement" else ""
 
 codeTd :: Bool -> Maybe Html -> Html
 codeTd _ Nothing = td mempty ! A.class_ (stringValue "blob-code blob-code-empty empty-cell")

From 985afd797b1c557b3e326bdf3e109215ab9e5d24 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 18:18:15 -0500
Subject: [PATCH 251/259] Revert "Remove the old definitions."

This reverts commit bdc9d50a5bf0e05ea6cd04e5603ab85911cc4314.
---
 src/Line.hs | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/Line.hs b/src/Line.hs
index 9b1a3133e..21a2f61d9 100644
--- a/src/Line.hs
+++ b/src/Line.hs
@@ -44,6 +44,9 @@ instance ToMarkup a => ToMarkup (Bool, Int, Line a) where
     _ -> cell "num" (string $ show num) <> cell "code" (toMarkup line) <> string "\n"
     where cell kind = td ! A.class_ (toClass kind)
           toClass kind = stringValue $ "blob-" ++ kind ++ if hasChanges then " blob-" ++ kind ++ "-replacement" else ""
+  toMarkup (_, _, line@EmptyLine) = td mempty ! A.class_ (stringValue "blob-num blob-num-empty empty-cell") <> toMarkup line <> string "\n"
+  toMarkup (True, num, line@(Line _)) = td (string $ show num) ! A.class_ (stringValue "blob-num blob-num-replacement") <> toMarkup line <> string "\n"
+  toMarkup (_, num, line@(Line _)) = td (string $ show num) ! A.class_ (stringValue "blob-num") <> toMarkup line <> string "\n"
 
 codeTd :: Bool -> Maybe Html -> Html
 codeTd _ Nothing = td mempty ! A.class_ (stringValue "blob-code blob-code-empty empty-cell")

From 759b008000f3bf770d40ac86fd1ffe2e9406260c Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 18:18:19 -0500
Subject: [PATCH 252/259] Revert "Define toMarkup over Bool/Int/Line triples by
 pattern matching."

This reverts commit 7f5f4ca3e690ccab67ac4d1536d80c415e51b791.
---
 src/Line.hs | 5 -----
 1 file changed, 5 deletions(-)

diff --git a/src/Line.hs b/src/Line.hs
index 21a2f61d9..cff4c2fb6 100644
--- a/src/Line.hs
+++ b/src/Line.hs
@@ -39,11 +39,6 @@ instance Monoid (Line a) where
   mappend (Line xs) (Line ys) = Line (xs <> ys)
 
 instance ToMarkup a => ToMarkup (Bool, Int, Line a) where
-  toMarkup (hasChanges, num, line) = case line of
-    EmptyLine -> td mempty ! A.class_ (stringValue "blob-num blob-num-empty empty-cell") <> td mempty ! A.class_ (stringValue "blob-code blob-code-empty empty-cell") <> string "\n"
-    _ -> cell "num" (string $ show num) <> cell "code" (toMarkup line) <> string "\n"
-    where cell kind = td ! A.class_ (toClass kind)
-          toClass kind = stringValue $ "blob-" ++ kind ++ if hasChanges then " blob-" ++ kind ++ "-replacement" else ""
   toMarkup (_, _, line@EmptyLine) = td mempty ! A.class_ (stringValue "blob-num blob-num-empty empty-cell") <> toMarkup line <> string "\n"
   toMarkup (True, num, line@(Line _)) = td (string $ show num) ! A.class_ (stringValue "blob-num blob-num-replacement") <> toMarkup line <> string "\n"
   toMarkup (_, num, line@(Line _)) = td (string $ show num) ! A.class_ (stringValue "blob-num") <> toMarkup line <> string "\n"

From 124ff65c91b2bd1d5405a01594a64f9dc1b8e295 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 18:19:30 -0500
Subject: [PATCH 253/259] Remove the pattern matches on Line.

---
 src/Line.hs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/Line.hs b/src/Line.hs
index cff4c2fb6..7a702b3ff 100644
--- a/src/Line.hs
+++ b/src/Line.hs
@@ -40,8 +40,8 @@ instance Monoid (Line a) where
 
 instance ToMarkup a => ToMarkup (Bool, Int, Line a) where
   toMarkup (_, _, line@EmptyLine) = td mempty ! A.class_ (stringValue "blob-num blob-num-empty empty-cell") <> toMarkup line <> string "\n"
-  toMarkup (True, num, line@(Line _)) = td (string $ show num) ! A.class_ (stringValue "blob-num blob-num-replacement") <> toMarkup line <> string "\n"
-  toMarkup (_, num, line@(Line _)) = td (string $ show num) ! A.class_ (stringValue "blob-num") <> toMarkup line <> string "\n"
+  toMarkup (True, num, line) = td (string $ show num) ! A.class_ (stringValue "blob-num blob-num-replacement") <> toMarkup line <> string "\n"
+  toMarkup (_, num, line) = td (string $ show num) ! A.class_ (stringValue "blob-num") <> toMarkup line <> string "\n"
 
 codeTd :: Bool -> Maybe Html -> Html
 codeTd _ Nothing = td mempty ! A.class_ (stringValue "blob-code blob-code-empty empty-cell")

From ac867437f0e627748478cd05c24a13ff5a3840b6 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 18:20:20 -0500
Subject: [PATCH 254/259] Handle the hasChanges case inline.

---
 src/Line.hs | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/src/Line.hs b/src/Line.hs
index 7a702b3ff..44904a31e 100644
--- a/src/Line.hs
+++ b/src/Line.hs
@@ -40,8 +40,7 @@ instance Monoid (Line a) where
 
 instance ToMarkup a => ToMarkup (Bool, Int, Line a) where
   toMarkup (_, _, line@EmptyLine) = td mempty ! A.class_ (stringValue "blob-num blob-num-empty empty-cell") <> toMarkup line <> string "\n"
-  toMarkup (True, num, line) = td (string $ show num) ! A.class_ (stringValue "blob-num blob-num-replacement") <> toMarkup line <> string "\n"
-  toMarkup (_, num, line) = td (string $ show num) ! A.class_ (stringValue "blob-num") <> toMarkup line <> string "\n"
+  toMarkup (hasChanges, num, line) = td (string $ show num) ! A.class_ (stringValue $ if hasChanges then "blob-num blob-num-replacement" else "blob-num") <> toMarkup line <> string "\n"
 
 codeTd :: Bool -> Maybe Html -> Html
 codeTd _ Nothing = td mempty ! A.class_ (stringValue "blob-code blob-code-empty empty-cell")

From cbd09870104244337b277c5f72af213f7c3fae2f Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 18:22:33 -0500
Subject: [PATCH 255/259] Mark up the code cell inline too.

---
 src/Line.hs | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/Line.hs b/src/Line.hs
index 44904a31e..61f67dc45 100644
--- a/src/Line.hs
+++ b/src/Line.hs
@@ -40,7 +40,9 @@ instance Monoid (Line a) where
 
 instance ToMarkup a => ToMarkup (Bool, Int, Line a) where
   toMarkup (_, _, line@EmptyLine) = td mempty ! A.class_ (stringValue "blob-num blob-num-empty empty-cell") <> toMarkup line <> string "\n"
-  toMarkup (hasChanges, num, line) = td (string $ show num) ! A.class_ (stringValue $ if hasChanges then "blob-num blob-num-replacement" else "blob-num") <> toMarkup line <> string "\n"
+  toMarkup (hasChanges, num, Line contents)
+    = td (string $ show num) ! A.class_ (stringValue $ if hasChanges then "blob-num blob-num-replacement" else "blob-num")
+    <> td (mconcat $ toMarkup <$> contents) ! A.class_ (stringValue $ if hasChanges then "blob-code blob-code-replacement" else "blob-code") <> string "\n"
 
 codeTd :: Bool -> Maybe Html -> Html
 codeTd _ Nothing = td mempty ! A.class_ (stringValue "blob-code blob-code-empty empty-cell")

From 91bf531af9c2423bb9d970973ca286b93eadaad3 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 18:23:34 -0500
Subject: [PATCH 256/259] Mark up empty code cells directly.

---
 src/Line.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Line.hs b/src/Line.hs
index 61f67dc45..e34e8ced8 100644
--- a/src/Line.hs
+++ b/src/Line.hs
@@ -39,7 +39,7 @@ instance Monoid (Line a) where
   mappend (Line xs) (Line ys) = Line (xs <> ys)
 
 instance ToMarkup a => ToMarkup (Bool, Int, Line a) where
-  toMarkup (_, _, line@EmptyLine) = td mempty ! A.class_ (stringValue "blob-num blob-num-empty empty-cell") <> toMarkup line <> string "\n"
+  toMarkup (_, _, EmptyLine) = td mempty ! A.class_ (stringValue "blob-num blob-num-empty empty-cell") <> td mempty ! A.class_ (stringValue "blob-code blob-code-empty empty-cell") <> string "\n"
   toMarkup (hasChanges, num, Line contents)
     = td (string $ show num) ! A.class_ (stringValue $ if hasChanges then "blob-num blob-num-replacement" else "blob-num")
     <> td (mconcat $ toMarkup <$> contents) ! A.class_ (stringValue $ if hasChanges then "blob-code blob-code-replacement" else "blob-code") <> string "\n"

From 3f2af1826aa9dd17233b129396a7ef638272e3a5 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 18:23:58 -0500
Subject: [PATCH 257/259] Remove the ToMarkup instance for Line.

---
 src/Line.hs | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/src/Line.hs b/src/Line.hs
index e34e8ced8..38dfe6793 100644
--- a/src/Line.hs
+++ b/src/Line.hs
@@ -48,7 +48,3 @@ codeTd :: Bool -> Maybe Html -> Html
 codeTd _ Nothing = td mempty ! A.class_ (stringValue "blob-code blob-code-empty empty-cell")
 codeTd True (Just el) = td el ! A.class_ (stringValue "blob-code blob-code-replacement")
 codeTd False (Just el) = td el ! A.class_ (stringValue "blob-code")
-
-instance ToMarkup a => ToMarkup (Line a) where
-  toMarkup EmptyLine = codeTd False Nothing
-  toMarkup (Line contents) = codeTd False . Just . mconcat $ toMarkup <$> contents

From 773f98c13ece373aea4d99e782f5e8461fbbc8bd Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Tue, 22 Dec 2015 18:24:20 -0500
Subject: [PATCH 258/259] Remove codeTd.

---
 src/Line.hs | 5 -----
 1 file changed, 5 deletions(-)

diff --git a/src/Line.hs b/src/Line.hs
index 38dfe6793..c1d748f8b 100644
--- a/src/Line.hs
+++ b/src/Line.hs
@@ -43,8 +43,3 @@ instance ToMarkup a => ToMarkup (Bool, Int, Line a) where
   toMarkup (hasChanges, num, Line contents)
     = td (string $ show num) ! A.class_ (stringValue $ if hasChanges then "blob-num blob-num-replacement" else "blob-num")
     <> td (mconcat $ toMarkup <$> contents) ! A.class_ (stringValue $ if hasChanges then "blob-code blob-code-replacement" else "blob-code") <> string "\n"
-
-codeTd :: Bool -> Maybe Html -> Html
-codeTd _ Nothing = td mempty ! A.class_ (stringValue "blob-code blob-code-empty empty-cell")
-codeTd True (Just el) = td el ! A.class_ (stringValue "blob-code blob-code-replacement")
-codeTd False (Just el) = td el ! A.class_ (stringValue "blob-code")

From cb56c621e0c08828ab15dc1214f56771246af71b Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@github.com>
Date: Sun, 27 Dec 2015 12:16:19 -0500
Subject: [PATCH 259/259] Whoops.

---
 src/Range.hs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Range.hs b/src/Range.hs
index 554c98509..c7cdb88ab 100644
--- a/src/Range.hs
+++ b/src/Range.hs
@@ -4,7 +4,7 @@ import Control.Applicative ((<|>))
 import qualified Data.Char as Char
 import Data.Maybe (fromMaybe)
 
-  -- | A half-open interval of integers, defined by start & end indices.
+-- | A half-open interval of integers, defined by start & end indices.
 data Range = Range { start :: !Int, end :: !Int }
   deriving (Eq, Show)