;tools: changelog: updates

bin/changelog.hs

@@ -14,6 +14,15 @@
 -- Manipulate a hledger changelog. Currently does one thing: prompts
 -- for a rewrite of the oldest uncategorised pending changelog item
 -- and updates the file, printing a diff.
+--
+-- My workflow:
+-- - In a terminal window (not emacs shell, it will hang) run this on a CHANGES.md file
+-- - Edit the changelog item to changelog-readiness (if needed)
+-- - Save and quit (C-x #) to do the next; it will exit after the last. Or C-x C-x to stop.
+-- - On the side keep an auto-reverting editor open on the file to watch progress or for fixups.
+-- It might seem a bit pointless, but it made this old chore much more
+-- pleasant. I can do just one, or more as I feel it, and my attention
+-- is not dragged on by pending items.
 
 {-# LANGUAGE DeriveAnyClass #-}
 {-# LANGUAGE DeriveGeneric #-}
@@ -26,19 +35,12 @@ import GHC.Generics
 import Data.List.Extra
 import qualified Data.Text as T
 import System.Environment
-import System.IO
+import System.IO.Extra
+-- import System.IO
 import System.Process
 import Text.Printf
 import Hledger.Utils
 
--- The one-line heading for a top level section in the changelog,
--- with the leading #(s) removed.
-type ChangelogHeading = String
-
--- One change description in the changelog, with the list bullet and
--- corresponding indentation removed.
-type ChangelogItem = String
-
 -- A top level section in the changelog, corresponding to one release.
 data ChangelogSection = ChangelogSection {
    heading          :: ChangelogHeading
@@ -47,46 +49,70 @@ data ChangelogSection = ChangelogSection {
   ,improvementitems :: [ChangelogItem]
   ,fixitems         :: [ChangelogItem]
   }
-  deriving (Show, Generic, Default)
+  deriving (Show, Eq, Generic, Default)
+
+-- The one-line heading for a top level section in the changelog,
+-- with the leading #(s) removed.
+type ChangelogHeading = String
+
+-- One change description in the changelog, with the list bullet and
+-- corresponding indentation removed.
+type ChangelogItem = String
 
 main = do
-  (i:_) <- getArgs
+  (f:_) <- getArgs
+  go f
 
+go f = do
   -- read specified changelog
-  (preamble:first:rest) <- splitOn "\n# " <$> readFile i
+  (preamble:first:rest) <- splitOn "\n# " <$> readFile f
   let
-    o = i ++ ".new"
+    g = f ++ ".new"
     s@ChangelogSection{..} = readSection first
+
+  -- ask for an edit of this item's text
   s' <- editOneUnknown s
 
-  -- write back to new file
-  writeFile o $ init $ unlines $
-     preamble :
-     showSection s' :
-     map ("# "++) rest
-
-  -- show the diff
-  system' $ printf "diff %s %s" i o
-
-  -- overwrite the old file
-  system' $ printf "mv %s %s" o i
+  if s' == s
+  then return ()  -- if it's unchanged, quit
+  else do
+    -- otherwise write to a temp file
+    writeFile g $ init $ unlines $
+      preamble :
+      showSection s' :
+      map ("# "++) rest
+    -- and show the diff
+    system' $ printf "diff %s %s" f g
+    -- and replace the old file
+    system' $ printf "mv %s %s" g f
+    -- and repeat
+    go f
 
 editOneUnknown :: ChangelogSection -> IO ChangelogSection
 editOneUnknown s@ChangelogSection{..}
   | null unknownitems = return s
   | otherwise = do
-    let u = last unknownitems
-    putStrLn "Old:\n"
-    putStrLn u
-    putStrLn "New: (prefix with feat:/imp:/fix: to categorise, ctrl-d to finish):\n" -- Just an = keeps it unchanged, empty string removes it.\n"
-    i <- getContents
-    let s' =
-          case i of
-            'f':'e':'a':'t':':':' ':t -> s{featureitems     = readItem t : featureitems}
-            'f':'i':'x':':':' ':t     -> s{fixitems         = readItem t : fixitems}
-            'i':'m':'p':':':' ':t     -> s{improvementitems = readItem t : improvementitems}
-            t                         -> s{improvementitems = readItem t : improvementitems}
-    return s'{unknownitems=init unknownitems}
+    let
+      s' = s{unknownitems=init unknownitems}
+      u = last unknownitems
+    new <- textEditEditor u
+    return $ case new of
+      'f':'e':'a':'t':':':' ':t -> s'{featureitems     = readItem t : featureitems}
+      'f':'i':'x':':':' ':t     -> s'{fixitems         = readItem t : fixitems}
+      'i':'m':'p':':':' ':t     -> s'{improvementitems = readItem t : improvementitems}
+      t                         -> s'{improvementitems = readItem t : improvementitems}
+
+textEditEditor t = withTempFile $ \f -> do
+  writeFile f t
+  ed <- getEnv "EDITOR"
+  system $ printf "%s %s" ed f
+  readFile f
+
+-- textEditTty u = do    
+--     putStrLn "Old:"
+--     putStrLn u
+--     putStrLn "New: (prefix with feat:/imp:/fix: to categorise, ctrl-d to finish):\n" -- Just an = keeps it unchanged, empty string removes it."
+--     getContents
 
 -- Parse a changelog section which may or may not have the Features/Improvements/Fixes subheadings.
 readSection :: String -> ChangelogSection