diff hgext/histedit.py @ 31056:37ab9e20991c

histedit: modify rollup to discard date from the rollup commit (issue4820)

This change adjusts and documents the new behaviour of 'roll'. It now fits nicely
with the behaviour of 'commit --amend' and the 'edit' action, by discarding the
date as well as the commit message of the second commit. Previously it used the
later date, like 'fold', but this often wasn't desirable, for example, in the
common use case of using 'roll' to add forgotten changes to a changeset
(because 'hg add' was previously forgotten or not all changes were identified
while using 'hg record').

--- a/hgext/histedit.py	Sat Feb 18 21:30:28 2017 +1100
+++ b/hgext/histedit.py	Sat Feb 18 21:30:28 2017 +1100
@@ -36,7 +36,7 @@
  #  p, pick = use commit
  #  e, edit = use commit, but stop for amending
  #  f, fold = use commit, but combine it with the one above
- #  r, roll = like fold, but discard this commit's description
+ #  r, roll = like fold, but discard this commit's description and date
  #  d, drop = remove commit from history
  #  m, mess = edit commit message without changing commit content
  #
@@ -58,7 +58,7 @@
  #  p, pick = use commit
  #  e, edit = use commit, but stop for amending
  #  f, fold = use commit, but combine it with the one above
- #  r, roll = like fold, but discard this commit's description
+ #  r, roll = like fold, but discard this commit's description and date
  #  d, drop = remove commit from history
  #  m, mess = edit commit message without changing commit content
  #
@@ -725,6 +725,15 @@
         """
         return True
 
+    def firstdate(self):
+        """Returns true if the rule should preserve the date of the first
+        change.
+
+        This exists mainly so that 'rollup' rules can be a subclass of
+        'fold'.
+        """
+        return False
+
     def finishfold(self, ui, repo, ctx, oldctx, newnode, internalchanges):
         parent = ctx.parents()[0].node()
         repo.ui.pushbuffer()
@@ -743,7 +752,10 @@
                 [oldctx.description()]) + '\n'
         commitopts['message'] = newmessage
         # date
-        commitopts['date'] = max(ctx.date(), oldctx.date())
+        if self.firstdate():
+            commitopts['date'] = ctx.date()
+        else:
+            commitopts['date'] = max(ctx.date(), oldctx.date())
         extra = ctx.extra().copy()
         # histedit_source
         # note: ctx is likely a temporary commit but that the best we can do
@@ -810,7 +822,7 @@
         return True
 
 @action(["roll", "r"],
-        _("like fold, but discard this commit's description"))
+        _("like fold, but discard this commit's description and date"))
 class rollup(fold):
     def mergedescs(self):
         return False
@@ -818,6 +830,9 @@
     def skipprompt(self):
         return True
 
+    def firstdate(self):
+        return True
+
 @action(["drop", "d"],
         _('remove commit from history'))
 class drop(histeditaction):
@@ -887,7 +902,7 @@
 
     - `fold` to combine it with the preceding changeset (using the later date)
 
-    - `roll` like fold, but discarding this commit's description
+    - `roll` like fold, but discarding this commit's description and date
 
     - `edit` to edit this changeset (preserving date)