diff --git a/src/Algorithm.hs b/src/Algorithm.hs
index 89ddbf1ac..2c97488ad 100644
--- a/src/Algorithm.hs
+++ b/src/Algorithm.hs
@@ -3,7 +3,8 @@ module Algorithm where
 
 import Control.Applicative (liftA2)
 import Control.Monad (guard, join)
-import Control.Monad.Free.Freer
+import Control.Monad.Free (wrap)
+import Control.Monad.Free.Freer hiding (wrap)
 import Data.Function (on)
 import Data.Functor.Both
 import Data.Functor.Classes
diff --git a/src/Data/Syntax.hs b/src/Data/Syntax.hs
index 46018e432..716bcb1cb 100644
--- a/src/Data/Syntax.hs
+++ b/src/Data/Syntax.hs
@@ -25,30 +25,38 @@ import Term
 
 -- Combinators
 
+-- | Lift syntax and an annotation into a term, injecting the syntax into a union & ensuring the annotation encompasses all children.
 makeTerm :: (HasCallStack, f :< fs, Semigroup a, Apply1 Foldable fs) => a -> f (Term (Union fs) a) -> Term (Union fs) a
 makeTerm a = makeTerm' a . inj
 
+-- | Lift a union and an annotation into a term, ensuring the annotation encompasses all children.
 makeTerm' :: (HasCallStack, Semigroup a, Foldable f) => a -> f (Term f a) -> Term f a
 makeTerm' a f = cofree (sconcat (a :| (headF . runCofree <$> toList f)) :< f)
 
+-- | Lift non-empty syntax into a term, injecting the syntax into a union & appending all subterms’.annotations to make the new term’s annotation.
 makeTerm1 :: (HasCallStack, f :< fs, Semigroup a, Apply1 Foldable fs) => f (Term (Union fs) a) -> Term (Union fs) a
 makeTerm1 = makeTerm1' . inj
 
+-- | Lift a non-empty union into a term, appending all subterms’.annotations to make the new term’s annotation.
 makeTerm1' :: (HasCallStack, Semigroup a, Foldable f) => f (Term f a) -> Term f a
 makeTerm1' f = case toList f of
   a : _ -> makeTerm' (headF (runCofree a)) f
   _ -> error "makeTerm1': empty structure"
 
+-- | Construct an empty term at the current position.
 emptyTerm :: (HasCallStack, Empty :< fs, Apply1 Foldable fs) => Assignment.Assignment ast grammar (Term (Union fs) (Record Assignment.Location))
 emptyTerm = makeTerm <$> Assignment.location <*> pure Empty
 
+-- | Catch assignment errors into an error term.
 handleError :: (HasCallStack, Error :< fs, Show grammar, Apply1 Foldable fs) => Assignment.Assignment ast grammar (Term (Union fs) (Record Assignment.Location)) -> Assignment.Assignment ast grammar (Term (Union fs) (Record Assignment.Location))
 handleError = flip catchError (\ err -> makeTerm <$> Assignment.location <*> pure (errorSyntax (either id show <$> err) []) <* Assignment.source)
 
+-- | Catch parse errors into an error term.
 parseError :: (HasCallStack, Error :< fs, Bounded grammar, Ix grammar, Apply1 Foldable fs) => Assignment.Assignment ast grammar (Term (Union fs) (Record Assignment.Location))
 parseError = makeTerm <$> Assignment.symbol maxBound <*> pure (Error (getCallStack (freezeCallStack callStack)) [] Nothing []) <* Assignment.source
 
 
+-- | Match context terms before a subject term, wrapping both up in a Context term if any context terms matched, or otherwise returning the subject term.
 contextualize :: (HasCallStack, Context :< fs, Alternative m, Semigroup a, Apply1 Foldable fs)
               => m (Term (Union fs) a)
               -> m (Term (Union fs) a)
@@ -58,6 +66,7 @@ contextualize context rule = make <$> Assignment.manyThrough context rule
           Just cs -> makeTerm1 (Context cs node)
           _ -> node
 
+-- | Match context terms after a subject term and before a delimiter, returning the delimiter paired with a Context term if any context terms matched, or the subject term otherwise.
 postContextualizeThrough :: (HasCallStack, Context :< fs, Alternative m, Semigroup a, Apply1 Foldable fs)
                          => m (Term (Union fs) a)
                          -> m (Term (Union fs) a)
@@ -68,6 +77,7 @@ postContextualizeThrough context rule end = make <$> rule <*> Assignment.manyThr
           Just cs -> (makeTerm1 (Context cs node), end)
           _ -> (node, end)
 
+-- | Match context terms after a subject term, wrapping both up in a Context term if any context terms matched, or otherwise returning the subject term.
 postContextualize :: (HasCallStack, Context :< fs, Alternative m, Semigroup a, Apply1 Foldable fs)
                   => m (Term (Union fs) a)
                   -> m (Term (Union fs) a)
@@ -77,6 +87,7 @@ postContextualize context rule = make <$> rule <*> many context
           Just cs -> makeTerm1 (Context cs node)
           _ -> node
 
+-- | Match infix terms separated by any of a list of operators, with optional context terms following each operand.
 infixContext :: (Context :< fs, Assignment.Parsing m, Semigroup a, HasCallStack, Apply1 Foldable fs)
              => m (Term (Union fs) a)
              -> m (Term (Union fs) a)
diff --git a/src/Data/Syntax/Assignment.hs b/src/Data/Syntax/Assignment.hs
index 72dcf3295..6d1cac7ff 100644
--- a/src/Data/Syntax/Assignment.hs
+++ b/src/Data/Syntax/Assignment.hs
@@ -76,7 +76,6 @@ module Data.Syntax.Assignment
 , children
 , advance
 , token
-, infixChoice
 , while
 , until
 , manyThrough
@@ -163,15 +162,14 @@ source = withFrozenCallStack $ Source `Then` return
 children :: HasCallStack => Assignment ast grammar a -> Assignment ast grammar a
 children forEach = withFrozenCallStack $ Children forEach `Then` return
 
+-- | Advance past the current node.
 advance :: HasCallStack => Assignment ast grammar ()
 advance = withFrozenCallStack $ Advance `Then` return
 
+-- | Match and advance past a node with the given symbol.
 token :: (Bounded grammar, Ix grammar, HasCallStack) => grammar -> Assignment ast grammar (Record Location)
 token s = symbol s <* advance
 
-infixChoice :: (Alternative m, HasCallStack) => m a -> m b -> [m (a -> b -> c)] -> m c
-infixChoice left right operators = (&) <$> left <*> choice operators <*> right
-
 
 -- | Collect a list of values passing a predicate.
 while :: (Alternative m, Monad m, HasCallStack) => (a -> Bool) -> m a -> m [a]
@@ -184,6 +182,7 @@ while predicate step = many $ do
 until :: (Alternative m, Monad m, HasCallStack) => (a -> Bool) -> m a -> m [a]
 until = while . (not .)
 
+-- | Match the first operand until the second operand matches, returning both results. Like 'manyTill', but returning the terminal value.
 manyThrough :: (Alternative m, HasCallStack) => m a -> m b -> m ([a], b)
 manyThrough step stop = go
   where go = (,) [] <$> stop <|> first . (:) <$> step <*> go
diff --git a/src/Interpreter.hs b/src/Interpreter.hs
index 33fcd316e..75fe7c5e1 100644
--- a/src/Interpreter.hs
+++ b/src/Interpreter.hs
@@ -9,8 +9,8 @@ module Interpreter
 import Algorithm
 import Control.Comonad (extract)
 import Control.Comonad.Cofree (unwrap)
-import Control.Monad.Free (cutoff)
-import Control.Monad.Free.Freer hiding (cutoff)
+import Control.Monad.Free (cutoff, wrap)
+import Control.Monad.Free.Freer hiding (cutoff, wrap)
 import Data.Align.Generic
 import Data.Functor.Both
 import Data.Functor.Classes (Eq1)
diff --git a/src/Language/Python/Syntax.hs b/src/Language/Python/Syntax.hs
index 815642c12..eb155e3af 100644
--- a/src/Language/Python/Syntax.hs
+++ b/src/Language/Python/Syntax.hs
@@ -470,15 +470,19 @@ ifClause = symbol IfClause *> children expressions
 conditionalExpression :: Assignment
 conditionalExpression = makeTerm <$> symbol ConditionalExpression <*> children (flip Statement.If <$> expression <*> expression <*> expressions)
 
+-- | Match a term optionally preceded by comment(s), or a sequence of comments if the term is not present.
 term :: Assignment -> Assignment
 term term = contextualize comment term <|> makeTerm1 <$> (Syntax.Context <$> some1 comment <*> emptyTerm)
 
+-- | Match a left-associated infix chain of terms, optionally followed by comments. Like 'chainl1' but assigning comment nodes automatically.
 chainl1Term :: Assignment -> Assignment.Assignment [] Grammar (Term -> Term -> Term) -> Assignment
 chainl1Term expr op = postContextualize (comment <|> symbol AnonLambda *> empty) expr `chainl1` op
 
+-- | Match a series of terms or comments until a delimiter is matched.
 manyTermsTill :: Show b => Assignment.Assignment [] Grammar Term -> Assignment.Assignment [] Grammar b -> Assignment.Assignment [] Grammar [Term]
 manyTermsTill step end = manyTill (step <|> comment) end
 
+-- | Match infix terms separated by any of a list of operators, assigning any comments following each operand.
 infixTerm :: HasCallStack
           => Assignment
           -> Assignment
diff --git a/src/Language/Ruby/Grammar.hs b/src/Language/Ruby/Grammar.hs
index 5ebd39157..df4a5d1e6 100644
--- a/src/Language/Ruby/Grammar.hs
+++ b/src/Language/Ruby/Grammar.hs
@@ -5,6 +5,8 @@ import Language.Haskell.TH
 import TreeSitter.Language
 import TreeSitter.Ruby
 
--- v2 - Bump to get file to change to force template haskell to regenerate.
+-- Regenerate template haskell code when these files change:
+addDependentFileRelative "../../../vendor/haskell-tree-sitter/languages/ruby/vendor/tree-sitter-ruby/src/parser.c"
+
 -- | Statically-known rules corresponding to symbols in the grammar.
 mkSymbolDatatype (mkName "Grammar") tree_sitter_ruby
diff --git a/src/Language/Ruby/Syntax.hs b/src/Language/Ruby/Syntax.hs
index 5371d6673..b19e51b6a 100644
--- a/src/Language/Ruby/Syntax.hs
+++ b/src/Language/Ruby/Syntax.hs
@@ -8,7 +8,8 @@ module Language.Ruby.Syntax
 
 import Data.Maybe (fromMaybe)
 import Data.Record
-import Data.Syntax (emptyTerm, makeTerm, parseError)
+import Data.Functor (void)
+import Data.Syntax (emptyTerm, makeTerm, parseError, handleError)
 import qualified Data.Syntax as Syntax
 import Data.Syntax.Assignment hiding (Assignment, Error)
 import qualified Data.Syntax.Assignment as Assignment
@@ -78,58 +79,64 @@ type Assignment = HasCallStack => Assignment.Assignment [] Grammar Term
 
 -- | Assignment from AST in Ruby’s grammar onto a program in Ruby’s syntax.
 assignment :: Assignment
-assignment = makeTerm <$> symbol Program <*> children (Syntax.Program <$> many expression) <|> parseError
+assignment = handleError $ makeTerm <$> symbol Program <*> children (Syntax.Program <$> many expression)
 
 expression :: Assignment
-expression =
-      beginBlock
-  <|> endBlock
-  <|> comment
-  <|> undef
-  <|> alias
-  <|> if'
-  <|> unless
-  <|> while'
-  <|> until'
-  <|> case'
-  <|> emptyStatement
+expression = handleError $
+      alias
   <|> assignment'
-  <|> unary
+  <|> begin
+  <|> beginBlock
   <|> binary
-  <|> literal
+  <|> block
+  <|> call
+  <|> case'
+  <|> class'
+  <|> comment
+  <|> conditional
+  <|> emptyStatement
+  <|> endBlock
+  <|> for
+  <|> heredoc
+  <|> identifier
+  <|> if'
   <|> keyword
-  <|> mk Return Statement.Return
-  <|> mk Yield Statement.Yield
+  <|> lambda
+  <|> literal
+  <|> method
+  <|> methodCall
   <|> mk Break Statement.Break
   <|> mk Next Statement.Continue
   <|> mk Redo Statement.Retry
   <|> mk Retry Statement.Retry
-  <|> for
-  <|> class'
-  <|> singletonClass
-  <|> method
-  <|> singletonMethod
-  <|> lambda
+  <|> mk Return Statement.Return
+  <|> mk Yield Statement.Yield
   <|> module'
-  <|> identifier
-  <|> scopeResolution
-  <|> conditional
-  <|> methodCall
-  <|> call
-  <|> subscript
-  <|> begin
+  <|> pair
+  <|> parenthesized_expressions
   <|> rescue
-  <|> block
-  <|> heredoc
+  <|> scopeResolution
+  <|> singletonClass
+  <|> singletonMethod
+  <|> subscript
+  <|> unary
+  <|> undef
+  <|> unless
+  <|> until'
+  <|> while'
   <|> parseError
-  where mk s construct = makeTerm <$> symbol s <*> children ((construct .) . fromMaybe <$> emptyTerm <*> optional (symbol ArgumentList *> children expression))
+  where mk s construct = makeTerm <$> symbol s <*> children ((construct .) . fromMaybe <$> emptyTerm <*> optional (symbol ArgumentList *> children expressions))
 
 expressions :: Assignment
 expressions = makeTerm <$> location <*> many expression
 
+parenthesized_expressions :: Assignment
+parenthesized_expressions = makeTerm <$> symbol ParenthesizedStatements <*> children (many expression)
+
 identifier :: Assignment
 identifier =
       mk Identifier
+  <|> mk Identifier'
   <|> mk Constant
   <|> mk InstanceVariable
   <|> mk ClassVariable
@@ -138,6 +145,9 @@ identifier =
   <|> mk Self
   <|> mk Super
   <|> mk Setter
+  <|> mk SplatArgument
+  <|> mk HashSplatArgument
+  <|> mk BlockArgument
   <|> mk ReservedIdentifier
   <|> mk Uninterpreted
   where mk s = makeTerm <$> symbol s <*> (Syntax.Identifier <$> source)
@@ -238,18 +248,20 @@ undef = makeTerm <$> symbol Undef <*> children (Expression.Call <$> name <*> som
   where name = makeTerm <$> location <*> (Syntax.Identifier <$> source)
 
 if' :: Assignment
-if' =
-      ifElsif If
-  <|> makeTerm <$> symbol IfModifier <*> children (flip Statement.If <$> expression <*> expression <*> emptyTerm)
-  where ifElsif s = makeTerm <$> symbol s <*> children (Statement.If <$> expression <*> expressions <*> (fromMaybe <$> emptyTerm <*> optional (ifElsif Elsif <|> else')))
+if' =  ifElsif If
+   <|> makeTerm <$> symbol IfModifier <*> children (flip Statement.If <$> expression <*> expression <*> emptyTerm)
+  where
+    ifElsif s = makeTerm <$> symbol s <*> children (Statement.If <$> expression <*> expressions' <*> (fromMaybe <$> emptyTerm <*> optional (ifElsif Elsif <|> else')))
+    expressions' = makeTerm <$> location <*> manyTill expression (void (symbol Else) <|> void (symbol Elsif) <|> eof)
 
 else' :: Assignment
 else' = makeTerm <$> symbol Else <*> children (many expression)
 
 unless :: Assignment
 unless =
-      makeTerm <$> symbol Unless         <*> children      (Statement.If <$> invert expression <*> expressions <*> (fromMaybe <$> emptyTerm <*> optional else'))
+      makeTerm <$> symbol Unless         <*> children      (Statement.If <$> invert expression <*> expressions' <*> (fromMaybe <$> emptyTerm <*> optional else'))
   <|> makeTerm <$> symbol UnlessModifier <*> children (flip Statement.If <$> expression <*> invert expression <*> emptyTerm)
+  where expressions' = makeTerm <$> location <*> manyTill expression (void (symbol Else) <|> eof)
 
 while' :: Assignment
 while' =
@@ -262,37 +274,33 @@ until' =
   <|> makeTerm <$> symbol UntilModifier <*> children (flip Statement.While <$> expression <*> invert expression)
 
 for :: Assignment
-for = makeTerm <$> symbol For <*> children (Statement.ForEach <$> vars <*> expression <*> expressions)
-  where vars = makeTerm <$> location <*> some expression
+for = makeTerm <$> symbol For <*> children (Statement.ForEach <$> (makeTerm <$> location <*> manyTill expression (symbol In)) <*> inClause <*> expressions)
+  where inClause = symbol In *> children (expression)
 
 case' :: Assignment
-case' = makeTerm <$> symbol Case <*> children (Statement.Match <$> expression <*> when')
+case' = makeTerm <$> symbol Case <*> children (Statement.Match <$> (symbol When *> emptyTerm <|> expression) <*> whens)
   where
-    when' =  makeTerm <$> symbol When <*> children (Statement.Pattern <$> (makeTerm <$> location <*> some pattern) <*> (when' <|> else' <|> expressions))
+    whens = makeTerm <$> location <*> many (when' <|> else' <|> expression)
+    when' = makeTerm <$> symbol When <*> children (Statement.Pattern <$> (makeTerm <$> location <*> some pattern) <*> whens)
     pattern = symbol Pattern *> children ((symbol SplatArgument *> children expression) <|> expression)
 
 subscript :: Assignment
-subscript = makeTerm <$> symbol ElementReference <*> children (Expression.Subscript <$> expression <*> many argument)
+subscript = makeTerm <$> symbol ElementReference <*> children (Expression.Subscript <$> expression <*> many expression)
 
 pair :: Assignment
 pair = makeTerm <$> symbol Pair <*> children (Literal.KeyValue <$> expression <*> expression)
-
-argument :: Assignment
-argument =
-      mk SplatArgument
-  <|> mk HashSplatArgument
-  <|> mk BlockArgument
-  <|> pair
-  <|> expression
-  where mk s = makeTerm <$> symbol s <*> (Syntax.Identifier <$> source)
+   <|> makeTerm <$> symbol Pair <*> (Syntax.Empty <$ source)
 
 methodCall :: Assignment
 methodCall = makeTerm <$> symbol MethodCall <*> children (Expression.Call <$> expression <*> args <*> (block <|> emptyTerm))
   where
-    args = (symbol ArgumentList <|> symbol ArgumentListWithParens) *> children (many argument) <|> pure []
+    args = (symbol ArgumentList <|> symbol ArgumentListWithParens) *> children (many expression) <|> pure []
+
 
 call :: Assignment
-call = makeTerm <$> symbol Call <*> children (Expression.MemberAccess <$> expression <*> expression)
+call = makeTerm <$> symbol Call <*> children (Expression.MemberAccess <$> expression <*> (expression <|> args))
+  where
+    args = (symbol ArgumentList <|> symbol ArgumentListWithParens) *> children (expressions)
 
 rescue :: Assignment
 rescue =  rescue'
@@ -331,7 +339,7 @@ assignment'
     expr =
           makeTerm <$> symbol RestAssignment <*> (Syntax.Identifier <$> source)
       <|> makeTerm <$> symbol DestructuredLeftAssignment <*> children (many expr)
-      <|> argument
+      <|> expression
 
 unary :: Assignment
 unary = symbol Unary >>= \ location ->
@@ -339,11 +347,11 @@ unary = symbol Unary >>= \ location ->
   <|> makeTerm location . Expression.Not <$> children ( symbol AnonBang *> expression )
   <|> makeTerm location . Expression.Not <$> children ( symbol AnonNot *> expression )
   <|> makeTerm location <$> children (Expression.Call <$> (makeTerm <$> symbol AnonDefinedQuestion <*> (Syntax.Identifier <$> source)) <*> some expression <*> emptyTerm)
+  <|> makeTerm location . Expression.Negate <$> children ( symbol AnonMinus' *> expression )
   <|> children ( symbol AnonPlus *> expression )
-  <|> makeTerm location . Expression.Negate <$> children expression -- Unary minus (e.g. `-a`). HiddenUnaryMinus nodes are hidden, so we can't match on the symbol.
 
 binary  :: Assignment
-binary = symbol Binary >>= \ loc -> children $ expression >>= \ lexpression -> go loc lexpression
+binary = symbol Binary >>= \ loc -> children $ (expression <|> emptyTerm) >>= \ lexpression -> go loc lexpression
   where
     go loc lexpression
        =  mk AnonAnd Expression.And
@@ -367,13 +375,15 @@ binary = symbol Binary >>= \ loc -> children $ expression >>= \ lexpression -> g
       <|> mk AnonAmpersand Expression.BAnd
       <|> mk AnonCaret Expression.BXOr
       <|> mk AnonPipe Expression.BOr
-      -- TODO: binary minus (hidden node). Doesn't work b/c we can't match hidden nodes (they aren't in the tree).
-      -- <|> mk HiddenBinaryMinus Expression.Minus
       <|> mk AnonPlus Expression.Plus
-      -- TODO: binary star (hidden node)
       <|> mk AnonSlash Expression.DividedBy
       <|> mk AnonPercent Expression.Modulo
       <|> mk AnonStarStar Expression.Power
+      -- TODO: binary minus and binary star (hidden nodes). Doesn't work b/c we
+      -- can't match hidden nodes (they aren't in the tree).
+      -- <|> mk HiddenBinaryMinus Expression.Minus
+      -- FIXME: This falls through to always assign binary as minus, which isn't correct.
+      <|> makeTerm loc <$> (Expression.Minus lexpression <$> (expression <|> emptyTerm))
       where mk s constr = makeTerm loc <$> (symbol s *> (constr lexpression <$> expression))
             mkNot s constr = makeTerm loc <$ symbol s <*> (Expression.Not <$> (makeTerm <$> location <*> (constr lexpression <$> expression)))
 
diff --git a/test/fixtures/ruby/for.A.rb b/test/fixtures/ruby/for.A.rb
index e012fdfd5..4b8947d88 100644
--- a/test/fixtures/ruby/for.A.rb
+++ b/test/fixtures/ruby/for.A.rb
@@ -5,3 +5,7 @@ end
 for x, y in z do
   f
 end
+
+for n in 1..3 do true end
+
+for n, m in 1..3 do true end
diff --git a/test/fixtures/ruby/for.diff+A.txt b/test/fixtures/ruby/for.diff+A.txt
deleted file mode 100644
index e68dcfcef..000000000
--- a/test/fixtures/ruby/for.diff+A.txt
+++ /dev/null
@@ -1,12 +0,0 @@
-{+(Program
-  (For
-    (Identifier)
-    (Other "in"
-      (Identifier))
-    (Identifier))
-  (For
-    (Identifier)
-    (Identifier)
-    (Other "in"
-      (Identifier))
-    (Identifier)))+}
diff --git a/test/fixtures/ruby/for.diff-A.txt b/test/fixtures/ruby/for.diff-A.txt
deleted file mode 100644
index e59be77ee..000000000
--- a/test/fixtures/ruby/for.diff-A.txt
+++ /dev/null
@@ -1,12 +0,0 @@
-{-(Program
-  (For
-    (Identifier)
-    (Other "in"
-      (Identifier))
-    (Identifier))
-  (For
-    (Identifier)
-    (Identifier)
-    (Other "in"
-      (Identifier))
-    (Identifier)))-}
diff --git a/test/fixtures/ruby/for.diffA-B.txt b/test/fixtures/ruby/for.diffA-B.txt
index 5f3ec59f3..4256ef986 100644
--- a/test/fixtures/ruby/for.diffA-B.txt
+++ b/test/fixtures/ruby/for.diffA-B.txt
@@ -1,20 +1,39 @@
 (Program
-  (For
-  { (Identifier)
-  ->(Identifier) }
+{+(For
+    (Identifier)
     (Other "in"
-    {+(ArrayLiteral
+      (ArrayLiteral
         (IntegerLiteral)
         (IntegerLiteral)
-        (IntegerLiteral))+}
-    {-(Identifier)-})
-  { (Identifier)
-  ->(MethodCall
+        (IntegerLiteral)))
+    (MethodCall
       (Identifier)
-      (Identifier)) })
+      (Identifier)))+}
+{-(For
+    (Identifier)
+    (Other "in"
+      (Identifier))
+    (Identifier))-}
 {-(For
     (Identifier)
     (Identifier)
     (Other "in"
       (Identifier))
-    (Identifier))-})
+    (Identifier))-}
+{-(For
+    (Identifier)
+    (Other "in"
+      (RangeExpression
+        (IntegerLiteral)
+        (Other "..")
+        (IntegerLiteral)))
+    (Boolean))-}
+{-(For
+    (Identifier)
+    (Identifier)
+    (Other "in"
+      (RangeExpression
+        (IntegerLiteral)
+        (Other "..")
+        (IntegerLiteral)))
+    (Boolean))-})
diff --git a/test/fixtures/ruby/for.diffB-A.txt b/test/fixtures/ruby/for.diffB-A.txt
index e13e35321..27985a0a0 100644
--- a/test/fixtures/ruby/for.diffB-A.txt
+++ b/test/fixtures/ruby/for.diffB-A.txt
@@ -1,9 +1,23 @@
 (Program
+{+(For
+    (Identifier)
+    (Other "in"
+      (Identifier))
+    (Identifier))+}
+{+(For
+    (Identifier)
+    (Identifier)
+    (Other "in"
+      (Identifier))
+    (Identifier))+}
   (For
   { (Identifier)
   ->(Identifier) }
     (Other "in"
-    {+(Identifier)+}
+    {+(RangeExpression
+        (IntegerLiteral)
+        (Other "..")
+        (IntegerLiteral))+}
     {-(ArrayLiteral
         (IntegerLiteral)
         (IntegerLiteral)
@@ -11,10 +25,13 @@
   { (MethodCall
       (Identifier)
       (Identifier))
-  ->(Identifier) })
+  ->(Boolean) })
 {+(For
     (Identifier)
     (Identifier)
     (Other "in"
-      (Identifier))
-    (Identifier))+})
+      (RangeExpression
+        (IntegerLiteral)
+        (Other "..")
+        (IntegerLiteral)))
+    (Boolean))+})
diff --git a/test/fixtures/ruby/for.parseA.txt b/test/fixtures/ruby/for.parseA.txt
index 190298e8c..54e14e14d 100644
--- a/test/fixtures/ruby/for.parseA.txt
+++ b/test/fixtures/ruby/for.parseA.txt
@@ -9,4 +9,21 @@
     (Identifier)
     (Other "in"
       (Identifier))
-    (Identifier)))
+    (Identifier))
+  (For
+    (Identifier)
+    (Other "in"
+      (RangeExpression
+        (IntegerLiteral)
+        (Other "..")
+        (IntegerLiteral)))
+    (Boolean))
+  (For
+    (Identifier)
+    (Identifier)
+    (Other "in"
+      (RangeExpression
+        (IntegerLiteral)
+        (Other "..")
+        (IntegerLiteral)))
+    (Boolean)))
diff --git a/test/fixtures/ruby/lambda.diffA-B.txt b/test/fixtures/ruby/lambda.diffA-B.txt
index 44c8907d9..eeff643dd 100644
--- a/test/fixtures/ruby/lambda.diffA-B.txt
+++ b/test/fixtures/ruby/lambda.diffA-B.txt
@@ -1,28 +1,29 @@
 (Program
-{+(AnonymousFunction
-    (ExpressionStatements
-      (Params
-        (Identifier))
-      (Binary
+{+(MethodCall
+    (Identifier)
+    (Params
+      (Identifier))
+    (Binary
+      (Identifier)
+      (Other "+")
+      (IntegerLiteral)))+}
+{-(MethodCall
+    (Identifier)
+    (Object))-}
+{-(MethodCall
+    (Identifier)
+    (Identifier))-}
+{-(MethodCall
+    (Identifier)
+    (Params
+      (Identifier)
+      (KeywordParameter
         (Identifier)
-        (Other "+")
-        (IntegerLiteral))))+}
-{-(AnonymousFunction
-    (ExpressionStatements))-}
-{-(AnonymousFunction
-    (ExpressionStatements
-      (Identifier)))-}
-{-(AnonymousFunction
-    (ExpressionStatements
-      (Params
+        (Boolean))
+      (OptionalParameter
         (Identifier)
-        (KeywordParameter
-          (Identifier)
-          (Boolean))
-        (OptionalParameter
-          (Identifier)
-          (Identifier)))
-      (IntegerLiteral)))-}
+        (Identifier)))
+    (IntegerLiteral))-}
 {-(AnonymousFunction
     (ExpressionStatements))-}
 {-(AnonymousFunction
diff --git a/test/fixtures/ruby/lambda.diffB-A.txt b/test/fixtures/ruby/lambda.diffB-A.txt
index ea0b28cc5..1e875c3ab 100644
--- a/test/fixtures/ruby/lambda.diffB-A.txt
+++ b/test/fixtures/ruby/lambda.diffB-A.txt
@@ -1,25 +1,26 @@
 (Program
-{+(AnonymousFunction
-    (ExpressionStatements))+}
-{+(AnonymousFunction
-    (ExpressionStatements
-      (Identifier)))+}
-  (AnonymousFunction
-    (ExpressionStatements
-      (Params
-      { (Identifier)
-      ->(Identifier) }
-      {+(KeywordParameter
-          (Identifier)
-          (Boolean))+}
-      {+(OptionalParameter
-          (Identifier)
-          (Identifier))+})
-    {+(IntegerLiteral)+}
-    {-(Binary
+{+(MethodCall
+    (Identifier)
+    (Object))+}
+{+(MethodCall
+    (Identifier)
+    (Identifier))+}
+  (MethodCall
+    (Identifier)
+    (Params
+    { (Identifier)
+    ->(Identifier) }
+    {+(KeywordParameter
         (Identifier)
-        (Other "+")
-        (IntegerLiteral))-}))
+        (Boolean))+}
+    {+(OptionalParameter
+        (Identifier)
+        (Identifier))+})
+  {+(IntegerLiteral)+}
+  {-(Binary
+      (Identifier)
+      (Other "+")
+      (IntegerLiteral))-})
 {+(AnonymousFunction
     (ExpressionStatements))+}
 {+(AnonymousFunction
diff --git a/test/fixtures/ruby/lambda.parseA.txt b/test/fixtures/ruby/lambda.parseA.txt
index 03d4ad93e..c80d1b432 100644
--- a/test/fixtures/ruby/lambda.parseA.txt
+++ b/test/fixtures/ruby/lambda.parseA.txt
@@ -1,20 +1,21 @@
 (Program
-  (AnonymousFunction
-    (ExpressionStatements))
-  (AnonymousFunction
-    (ExpressionStatements
-      (Identifier)))
-  (AnonymousFunction
-    (ExpressionStatements
-      (Params
+  (MethodCall
+    (Identifier)
+    (Object))
+  (MethodCall
+    (Identifier)
+    (Identifier))
+  (MethodCall
+    (Identifier)
+    (Params
+      (Identifier)
+      (KeywordParameter
         (Identifier)
-        (KeywordParameter
-          (Identifier)
-          (Boolean))
-        (OptionalParameter
-          (Identifier)
-          (Identifier)))
-      (IntegerLiteral)))
+        (Boolean))
+      (OptionalParameter
+        (Identifier)
+        (Identifier)))
+    (IntegerLiteral))
   (AnonymousFunction
     (ExpressionStatements))
   (AnonymousFunction
diff --git a/test/fixtures/ruby/lambda.parseB.txt b/test/fixtures/ruby/lambda.parseB.txt
index 6b17c9e35..c8546a99b 100644
--- a/test/fixtures/ruby/lambda.parseB.txt
+++ b/test/fixtures/ruby/lambda.parseB.txt
@@ -1,9 +1,9 @@
 (Program
-  (AnonymousFunction
-    (ExpressionStatements
-      (Params
-        (Identifier))
-      (Binary
-        (Identifier)
-        (Other "+")
-        (IntegerLiteral)))))
+  (MethodCall
+    (Identifier)
+    (Params
+      (Identifier))
+    (Binary
+      (Identifier)
+      (Other "+")
+      (IntegerLiteral))))
diff --git a/test/fixtures/ruby/when.A.rb b/test/fixtures/ruby/when.A.rb
index 92a40caf6..30cde71fd 100644
--- a/test/fixtures/ruby/when.A.rb
+++ b/test/fixtures/ruby/when.A.rb
@@ -1,3 +1,7 @@
 case foo
 when bar
 end
+
+case
+when true; 'foo'
+end
diff --git a/test/fixtures/ruby/when.B.rb b/test/fixtures/ruby/when.B.rb
index 3c8eff26f..3a074ae40 100644
--- a/test/fixtures/ruby/when.B.rb
+++ b/test/fixtures/ruby/when.B.rb
@@ -1,4 +1,7 @@
 case foo
 when bar
   baz
+when a, b
+else
+  bat
 end
diff --git a/test/fixtures/ruby/when.diff-B.txt b/test/fixtures/ruby/when.diff-B.txt
index 7f1fa4303..8831c29d9 100644
--- a/test/fixtures/ruby/when.diff-B.txt
+++ b/test/fixtures/ruby/when.diff-B.txt
@@ -4,4 +4,11 @@
     (When
       (Args
         (Identifier))
-      (Identifier))))-}
+      (Identifier)
+      (When
+        (Args
+          (Identifier))
+        (Args
+          (Identifier))
+        (Else
+          (Identifier))))))-}
diff --git a/test/fixtures/ruby/when.diffA-B.txt b/test/fixtures/ruby/when.diffA-B.txt
index db08f1d08..a2abee676 100644
--- a/test/fixtures/ruby/when.diffA-B.txt
+++ b/test/fixtures/ruby/when.diffA-B.txt
@@ -4,4 +4,16 @@
     (When
       (Args
         (Identifier))
-    {+(Identifier)+})))
+    {+(Identifier)+}
+    {+(When
+        (Args
+          (Identifier))
+        (Args
+          (Identifier))
+        (Else
+          (Identifier)))+}))
+{-(Case
+    (When
+      (Args
+        (Boolean))
+      (StringLiteral)))-})
diff --git a/test/fixtures/ruby/when.diffB-A.txt b/test/fixtures/ruby/when.diffB-A.txt
index 8d733dc1f..6c0f49304 100644
--- a/test/fixtures/ruby/when.diffB-A.txt
+++ b/test/fixtures/ruby/when.diffB-A.txt
@@ -4,4 +4,16 @@
     (When
       (Args
         (Identifier))
-    {-(Identifier)-})))
+    {-(Identifier)-}
+    {-(When
+        (Args
+          (Identifier))
+        (Args
+          (Identifier))
+        (Else
+          (Identifier)))-}))
+{+(Case
+    (When
+      (Args
+        (Boolean))
+      (StringLiteral)))+})
diff --git a/test/fixtures/ruby/when.parseA.txt b/test/fixtures/ruby/when.parseA.txt
index 723a79d0d..cac12eacd 100644
--- a/test/fixtures/ruby/when.parseA.txt
+++ b/test/fixtures/ruby/when.parseA.txt
@@ -3,4 +3,9 @@
     (Identifier)
     (When
       (Args
-        (Identifier)))))
+        (Identifier))))
+  (Case
+    (When
+      (Args
+        (Boolean))
+      (StringLiteral))))
diff --git a/test/fixtures/ruby/when.parseB.txt b/test/fixtures/ruby/when.parseB.txt
index 64e760f84..d24efe4c9 100644
--- a/test/fixtures/ruby/when.parseB.txt
+++ b/test/fixtures/ruby/when.parseB.txt
@@ -4,4 +4,11 @@
     (When
       (Args
         (Identifier))
-      (Identifier))))
+      (Identifier)
+      (When
+        (Args
+          (Identifier))
+        (Args
+          (Identifier))
+        (Else
+          (Identifier))))))
diff --git a/vendor/haskell-tree-sitter b/vendor/haskell-tree-sitter
index 45bbc5aff..415584f78 160000
--- a/vendor/haskell-tree-sitter
+++ b/vendor/haskell-tree-sitter
@@ -1 +1 @@
-Subproject commit 45bbc5aff11ac5d4364b024d5b8693c297ee9ebb
+Subproject commit 415584f7833c49bf06504c14b8fe7b613ae81fa1