squash: Make commit message editing more convenient

Very often, the commit message you want when squashing is the message
of the first patch. So instead of simply concatenating the messages of
all the patches, put a comment delimiter after the first one, and
ignore everything after the delimiter when reading the message back
in. If the user wants to use any part of the commented-out messages,
she can move text around however she wants, including deleting the
comment delimiter.

Signed-off-by: Karl Wiberg <kha@treskal.com>

2 files changed, 17 insertions, 4 deletions

diff --git a/stgit/commands/squash.py b/stgit/commands/squash.py
index d0be466..96b8da2 100644
--- a/stgit/commands/squash.py
+++ b/stgit/commands/squash.py
@@ -68,14 +68,17 @@ def _squash_patches(trans, patches, msg, save_template):
             return None
         cd = cd.set_tree(tree)
     if msg == None:
-        msg = '\n\n'.join('%s\n\n%s' % (pn.ljust(70, '-'),
-                                        trans.patches[pn].data.message)
-                          for pn in patches)
+        msg = utils.append_comment(
+            trans.patches[patches[0]].data.message,
+            '\n\n'.join('%s\n\n%s' % (pn.ljust(70, '-'),
+                                      trans.patches[pn].data.message)
+                        for pn in patches[1:]))
         if save_template:
             save_template(msg)
             raise SaveTemplateDone()
         else:
-            msg = utils.edit_string(msg, '.stgit-squash.txt').strip()
+            msg = utils.edit_string(msg, '.stgit-squash.txt')
+    msg = utils.strip_comment(msg).strip()
     cd = cd.set_message(msg)
 
     return cd
diff --git a/stgit/utils.py b/stgit/utils.py
index 1fa96c2..5c0e159 100644
--- a/stgit/utils.py
+++ b/stgit/utils.py
@@ -200,6 +200,16 @@ def edit_string(s, filename):
     os.remove(filename)
     return s
 
+def append_comment(s, comment, separator = '---'):
+    return ('%s\n\n%s\nEverything following the line with "%s" will be'
+            ' ignored\n\n%s' % (s, separator, separator, comment))
+
+def strip_comment(s, separator = '---'):
+    try:
+        return s[:s.index('\n%s\n' % separator)]
+    except ValueError:
+        return s
+
 def find_patch_name(patchname, unacceptable):
     """Find a patch name which is acceptable."""
     if unacceptable(patchname):