commit.hb: stop requiring a ChangeLog.txt entry for commits

Editing ChangeLog.txt means to manually maintain a modification history
in timestamp order. This isn't practical with the Git model, and blocks
handling patches, including PRs. It served well in a the linear
development model of CVS and SVN, but no longer with Git. Git also
handles the commiter, author, and commit/authoring timestamps
automatically, making our existing manual method obsolete. Manually
keeping a duplicate copy of the commit message also makes working on PRs
much complicated, as we need to keep these in sync while making changes.
Existing method also made the one-liner commit messages 100%
meaningless, repeating the author/timestamp, which is visible there on
most UIs already.

Git allows to list the changelog with this command, dynamically:

`$ git log --pretty=medium --no-merges --date=iso --stat HEAD~50..HEAD`

I'm suggesting a new way of keeping history, which solves all these
issues and makes working with the codebase simpler and aligns Harbour
with most other projects over the internet:

In the top line, put a one-liner description of the changes, prefixed
with the module where the change happened, e.g.:
hbmk2: add support for Windows ARM64

This replaces the existing manual author/timestamp header.

Then an empty line, followed by the description of the changes, and/or
here we can use the existing format:

* filename1.ext:
  ! fix foo bar
* filename2.ext:
  + add foo baz

Full commit message:
```
hbmk2: add support for Windows ARM64

* filename1.ext:
  ! fix foo bar
* filename2.ext:
  + add foo baz
```

Because the filenames are also redundant and shown by Git, I suggest
replacing the actual filenames with module names or other,
less-specific, but descriptive, short and recognizable pointer:

Further streamlined commit message:
```
hbmk2: add support for Windows ARM64

- fix foo bar
- add foo baz

Ref: <commit> #<pr>
Fixes #<issue>
Closes #<pr>
```

This also drop the `!`, `+`, `%`, `*`, `;` list marker in favour of
`-`. The text describes the nature of the change in more universal way
anyway.

I suggest wrapping the message body at 72 characters. Using Markdown
markup is fine. Adding pointers to commit hashes and/or GitHub issues/
PRs helps to put a commit in context.

When moving around patches made in the old way, I recommend stripping
the hunk dealing with `ChangeLog.txt` to ease the process. Manually
of e.g. with this command:

`$ filterdiff -p1 --exclude=ChangeLog.txt`

ChangeLog.txt

@@ -1,7 +1,21 @@
-/* Encoding: UTF-8 (No BOM)  Notation (in 5th column):
-     * Change  ! Fix  % Optimize  + Add  - Remove  ; Comment
-   Entries may not always be in chronological/commit order.
-   See license at the end of file. */
+/* Manual maintenance of ChangeLog.txt is deprecated. Please add a commit
+   message instead, following this format:
+   ```
+   module: add new feature
+
+   * change this bit
+   - add this bit
+   ! fix this bit
+   % optimize this bit
+   ; comment, or just use `-` for any item.
+
+   Ref: <commit> #<pr>
+   Fixes #<issue>
+   Closes #<pr>
+   ```
+
+   Use 'add'/'fix'/etc. Not 'added', 'adding' or 'adds'.
+ */
 
 2022-06-30 11:27 UTC Viktor Szakats
   * contrib/hbcrypto/3rd/ed25519/ed25519.diff

bin/commit.hb

@@ -38,12 +38,7 @@ PROCEDURE Main()
    LOCAL cLocalRoot
    LOCAL aFiles
    LOCAL aChanges
-   LOCAL cLog
-   LOCAL nStart, nEnd
-   LOCAL cMyName
    LOCAL cLogName
-   LOCAL lWasChangeLog
-   LOCAL cEOL
 
    IF "-c" $ cli_Options()
       CheckFileList( iif( Empty( cli_Values() ),, cli_Values() ) )
@@ -73,78 +68,10 @@ PROCEDURE Main()
       "-f" $ cli_Options() .OR. ;
       "--force" $ cli_Options()
 
-      cLogName := FindChangeLog( cVCS )
-      IF cLogName == ""
-         OutStd( hb_ProgName() + ": " + "cannot find ChangeLog file" + hb_eol() )
-         ErrorLevel( 2 )
-      ENDIF
-
-      IF "--check-only" $ cli_Options() .OR. ;
-         "--prepare-commit" $ cli_Options()
-
-         IF hb_AScan( aFiles, hb_FNameNameExt( cLogName ),,, .T. ) == 0
-            OutStd( hb_ProgName() + ": " + hb_StrFormat( "%1$s not updated. Run '%2$s %3$s' and retry.", cLogName, hb_FNameNameExt( hbshell_ProgName() ), CommitScript() ) + hb_eol() )
-            ErrorLevel( 3 )
-            RETURN
-         ELSE
-            IF ! GitIsMerge( cVCSDir )
-               cLog := GetLastEntry( MemoRead( cLogName ), @nStart, @nEnd )
-               IF ! cLog == ""
-                  IF "--prepare-commit" $ cli_Options() .AND. ! Empty( cli_Values() )
-                     hb_MemoWrit( cli_Values()[ 1 ], EntryToCommitMsg( cLog ) + hb_MemoRead( cli_Values()[ 1 ] ) )
-                  ELSE
-                     hbshell_gtSelect()
-#if 0
-                     /* if clipboard already contains part of the entry, do not overwrite it */
-                     IF ! hb_StrReplace( hb_gtInfo( HB_GTI_CLIPBOARDDATA ), Chr( 13 ) + Chr( 10 ) ) $ hb_StrReplace( cLog, Chr( 13 ) + Chr( 10 ) )
-                        hb_gtInfo( HB_GTI_CLIPBOARDDATA, EntryToCommitMsg( cLog ) )
-                     ENDIF
-#endif
-                  ENDIF
-               ENDIF
-            ENDIF
-         ENDIF
-
-      ELSEIF ! cLogName == ""
-
-         IF cVCS == "git"
-            cMyName := GitUser()
-         ELSE
-            IF ! GetEnv( _CONFIGENV_ ) == ""
-               cMyName := GetEnv( _CONFIGENV_ )
-            ELSEIF hb_vfExists( cLocalRoot + _CONFIGFIL_ )
-               cMyName := AllTrim( hb_MemoRead( cLocalRoot + _CONFIGFIL_ ) )
-            ELSE
-               cMyName := "Firstname Lastname (me example.org)"
-            ENDIF
-         ENDIF
+      IF ! "--check-only" $ cli_Options() .AND. ;
+         ! "--prepare-commit" $ cli_Options()
 
-         //
-
-         cLog := MemoRead( cLogName )
-         cEOL := hb_StrEOL( cLog )
-
-         GetLastEntry( cLog, @nStart, @nEnd )
-
-         IF nStart > 0
-
-            /* Strip last entry if it's empty to avoid adding double entries */
-            IF IsLastEntryEmpty( SubStr( cLog, nStart, nEnd - nStart ), cLogName, @lWasChangeLog )
-               OutStd( hb_ProgName() + ": " + hb_StrFormat( "Updating last empty %1$s entry", cLogName ) + hb_eol() )
-               cLog := Left( cLog, nStart - 1 ) + SubStr( cLog, nEnd )
-            ELSE
-               lWasChangelog := .T.
-            ENDIF
-
-            cLog := ;
-               Left( cLog, nStart - 1 ) + ;
-               MakeEntry( aChanges, cMyName, cLogName, lWasChangeLog, cEOL ) + cEOL + ;
-               SubStr( cLog, nStart )
-         ELSE
-            cLog += cEOL + MakeEntry( aChanges, cMyName, cLogName, .T., cEOL )
-         ENDIF
-
-         hb_MemoWrit( cLogName, cLog )
+         hb_MemoWrit( cLogName := cLocalRoot + "_commit.txt", MakeEntry( aChanges ) )
 
          OutStd( hb_ProgName() + ": " + hb_StrFormat( "Edit %1$s and commit", cLogName ) + hb_eol() )
 #if 0
@@ -226,25 +153,6 @@ STATIC FUNCTION InstallHook( cDir, cHookName, cCommand )
 
    RETURN hb_MemoWrit( cName, cFile + Chr( 10 ) + cCommand + Chr( 10 ) )
 
-STATIC FUNCTION FindChangeLog( cVCS )
-
-   LOCAL cDir
-   LOCAL cLogName
-
-   IF hb_vfExists( cLogName := "ChangeLog.txt" ) .OR. ;
-      hb_vfExists( cLogName := "ChangeLog" )
-      RETURN cLogName
-   ENDIF
-
-   cDir := iif( cVCS == "git", GitLocalRoot(), "" )
-
-   IF hb_vfExists( cLogName := cDir + "ChangeLog.txt" ) .OR. ;
-      hb_vfExists( cLogName := cDir + "ChangeLog" )
-      RETURN cLogName
-   ENDIF
-
-   RETURN ""
-
 STATIC FUNCTION GetLastEntry( cLog, /* @ */ nStart, /* @ */ nEnd )
 
    LOCAL cLogHeaderExp := "\n[1-2][0-9][0-9][0-9]-[0-1][0-9]-[0-3][0-9] [0-2][0-9]:[0-6][0-9] [\S ]*"
@@ -277,63 +185,15 @@ STATIC FUNCTION GetLastEntry( cLog, /* @ */ nStart, /* @ */ nEnd )
 
    RETURN cLog
 
-STATIC FUNCTION MakeEntry( aChanges, cMyName, cLogName, lAllowChangeLog, cEOL )
+STATIC FUNCTION MakeEntry( aChanges )
 
-   LOCAL nOffset := hb_UTCOffset()
-   LOCAL tDate := hb_DateTime()
-
-   LOCAL cLog
+   LOCAL cLog := "module: edit my changes" + hb_eol() + hb_eol()
    LOCAL cLine
 
-   tDate -= ( nOffset / 86400 )
-   nOffset := 0
-
-   IF nOffset == 0
-      cLog := hb_StrFormat( "%1$s UTC", ;
-         hb_TToC( tDate, "yyyy-mm-dd", "hh:mm" ) )
-   ELSE
-      cLog := hb_StrFormat( "%1$s UTC+%2$s%3$02d%4$02d", ;
-         hb_TToC( tDate, "yyyy-mm-dd", "hh:mm" ), ;
-         iif( nOffset < 0, "-", "+" ), ;
-         Int( Abs( nOffset ) / 3600 ), ;
-         Int( Abs( nOffset ) % 3600 / 60 ) )
-   ENDIF
-
-   cLog += " " + cMyName + cEOL
-
    FOR EACH cLine IN aChanges
-      IF lAllowChangeLog .OR. ! SubStr( cLine, 5 ) == hb_FNameNameExt( cLogName )
-         cLog += cLine + cEOL
-      ENDIF
-   NEXT
-
-   RETURN cLog
-
-STATIC FUNCTION IsLastEntryEmpty( cLog, cLogName, /* @ */ lChangeLog )
-
-   LOCAL cLine
-
-   lChangeLog := .F.
-
-   FOR EACH cLine IN hb_ATokens( cLog, .T. )
-      IF ! cLine:__enumIsFirst()
-         IF Empty( Left( cLine, 2 ) ) .AND. ! Empty( SubStr( cLine, 3, 1 ) )
-            IF SubStr( cLine, 5 ) == hb_FNameNameExt( cLogName )
-               lChangeLog := .T.
-            ENDIF
-         ELSEIF ! Empty( cLine )
-            RETURN .F.
-         ENDIF
-      ENDIF
+      cLog += cLine + hb_eol()
    NEXT
 
-   RETURN .T.
-
-/* If it's a single mod, include only the change text,
-   otherwise include the whole entry.
-   NOTE: It was confusing to mix the two styles, so for
-         now always include the complete log message. */
-STATIC FUNCTION EntryToCommitMsg( cLog )
    RETURN cLog
 
 STATIC FUNCTION VCSDetect( /* @ */ cVCSDir, /* @ */ cLocalRoot )
@@ -377,9 +237,6 @@ STATIC FUNCTION GitLocalRoot()
 
    RETURN iif( nResult == 0, hb_DirSepAdd( hb_DirSepToOS( hb_StrReplace( cStdOut, Chr( 13 ) + Chr( 10 ) ) ) ), "" )
 
-STATIC FUNCTION GitIsMerge( cGitDir )
-   RETURN hb_vfExists( cGitDir + "MERGE_MSG" )
-
 STATIC FUNCTION GitFileList()
 
    LOCAL cStdOut
@@ -397,14 +254,6 @@ STATIC FUNCTION GitFileList()
 
    RETURN aList
 
-STATIC FUNCTION GitUser()
-
-   LOCAL cName
-
-   hb_processRun( Shell() + " " + CmdEscape( "git config user.name" ),, @cName )
-
-   RETURN AllTrim( hb_StrReplace( cName, Chr( 10 ) + Chr( 13 ) ) )
-
 STATIC FUNCTION GitEditor()
 
    LOCAL cValue