[PATCH RFC] commit: add --amend option to amend the parent changeset

[Angel Ezquerra]

On Thu, Feb 2, 2012 at 1:35 PM, Idan Kamara <idankk86 at gmail.com> wrote:
> # HG changeset patch
> # User Idan Kamara <idankk86 at gmail.com>
> # Date 1328185747 -7200
> # Branch stable
> # Node ID cc7dec00d5016f03acf789c35ce6ef50b204f0cb
> # Parent  0620421044a2bcaafd054a6ee454614888699de8
> commit: add --amend option to amend the parent changeset
>
> Commits a new changeset incorporating both the changes to the given files
> and all the changes from the current parent changeset into the repository.
>
> You cannot amend public changesets. Amending a changeset with children
> results in a warning (we might want to forbid this).
>
> Behind the scenes, first commit the update as a regular child of the current
> parent. Then create a new commit on the parent's parents with the updated
> contents. Then change the working copy parent to this new combined changeset.
> Finally, strip the intermediate commit created in the beginning (might
> want to also strip the amended commit if it has no children).
>
> This is an RFC, which last discussed one year ago: http://markmail.org/message/skalggb4typm27um
>
> I think this attempt is less intrusive and more contained than the previous one
> (it was done quickly to see if there's interest, so still unfinished), with a
> much cleaner implementation (largely due to parren's work on evolution, thanks ;).
>
> It doesn't try to be too smart, and now that we have phases it should be safe.
>
> This is arguably one of the most common history editing operations. I don't
> think referring people to mq (or rollback, which is worse) for this is particularly good.
> It requires activating a 'heavy' extension and use new commands that the user
> isn't familiar with. This way the user is in familiar territory, knowing all the flags etc.
>

This is quite cool and a neat example of what can be done now that
mercurial tracks phases :-)

One thing that would be nice is to be able to just "amend" the commit
message (without modifying the patch file contents). I think _that_ is
probably _the_ most commonly requested history editing operation (at
least in my experience).

Angel