mutable-history / docs / evolve-faq.rst

Evolve How To

Add a changeset: commit

Just use commit as usual. New changesets will be in the draft phase.

Rewrite a changeset: amend

A new command hg amend is added by the extension. It writes a new changeset combining working-directory parent changes and parent. It will work on any draft or secret changeset. It will not work on public changesets.

To understand what the result of amend will be I use the two following aliases [1]:

# diff what amend will look likes
pdiff=diff --rev .^

# status what amend will look likes
pstatus=status --rev .^

It takes various options to pick an author, a date and the branch of the result... (see hg help amend for details).

This command can even be invoked on changesets with children (provided none is public) !


the amend command is very similar to mq's qrefresh, a refresh alias for amend is also available. But note that contrary to qrefresh, amend does not exclude changes on file not specified on the command line.

XXX add idank example

[1](added by

Move a changeset: graft

The graft command introduced in 2.0 allows to "copy changes from other branches onto the current branch".

The graft command has been altered to allow the creation of an obsolete marker indicating both the result cset and its source (actually recording changeset movements).

This is achieved using a new flag -O (or old-obsolete) [2].

XXX example


when using graft --continue after conflict resolution you MUST pass -O or -o flag again because they are not saved for now

[2]add this -O to graft instead of a dedicated command is probably abusive. But this was very convenient for experimental purposes. This will likely change in non experimental release.

Delete a changeset: kill

A new kill command allows removing a changeset.

Just use hg kill <some-rev>.

Moving within the history: up gdown and gup

While working on mutable part of the history you often need to move between mutable commit.

You just need to use standard update to work with evolve. For convenience, you can use hg gup to move to children commit or hg gdown to move to working directory parent commit.


those command only exist for the convenience of getting qpush and qpop feeling back.

Collapse changesets: amend

you can use amend -c to collapse multiple changeset in a single one.

Split a changeset

There is no official command to split a changeset. However is it easily achieved by manual operation:

### you want to split changeset A: 42
# update to A parent
$ hg up 42^
# restore content from A
$ hg revert -r 42 --all
# partially commit the first part
$ hg record
# commit the second part
$ hg commit
# informs mercurial of what appened
# current changeset (.) and previous one (.^) replace A (42)
$ hg kill --new . --new .^ 42

Update my current work in progess after a pull

Whenever you are working on some changesets, it is more likely that a pull will, eventually, import new changesets in your tree.

And it is likely that you will want your work in progress changsets to be rebased on the top of this newly imported subtree.

Doing so is only a matter of rebasing.

Move multiple changesets: rebase

You can still use rebase to move a whole segment of the changeset graph together.


Beware that rebasing obsolete changesets will result in conflicting versions of the changesets.

Stabilize history: stabilize

When you rewrite (amend) a changeset with children without rewriting those children you create unstable changesets and suspended obsolete changesets.

When you are finished amending a given changeset, you will want to declare it stable, in other words rebase its former descendants on its newest version. This is not done automatically to avoid the proliferation of useless hidden changesets.


hg stabilize have no --continue to use after conflict resolution


stabilization does not handle deletion yet.


obsolete currently relies on changesets in secret phase
to avoid exchanging obsolete and unstable changesets.

XXX details issue here

Fix my history afterward: kill -n

Sometimes you need to create an obsolete marker by hand. This may happen when upstream has applied some of your patches for example.

you can use hg kill --new <new-changeset> <old-changeset> to add obsolete marker.

Export to mq: synchronize

Another extension allows to export.

View change to your file

Another extension allows to export.

View diff from the last amend

An odiff alias have been added by

[alias] odiff = diff --rev 'limit(obsparents(.),1)' --rev .

View obsolete markers

hgview is the only viewer that support this feature. You need an experimental version available here:

$ hg clone

Important Note

View change to your file

Extinct changesets are hidden using the hidden feature of mercurial.

Only hg log and hgview support it. hg glog or other visual viewer don't.