subrepo: compare svn subrepo state to last committed revision
A subversion project revisions are a subset of the repository revisions, you
can ask subversion to update a working directory from one revision to another
without changing anything. Unfortunately, Mercurial will think the
subrepository has changed and will commit it again. To avoid useless commits,
we compare the subrepository state to its actual "parent" revision. To ensure
ascending compatibility with existing subrepositories which might reference
fake revisions, we also keep comparing with the subrepo working directory
revision.
NOTE: not sure if this should go in stable or not.
http://mercurial.selenic.com/bts/issue619
$ hg init
$ echo a > a
$ hg ci -Ama
adding a
$ echo b > b
$ hg branch b
marked working directory as branch b
$ hg ci -Amb
adding b
$ hg co -C 0
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
Fast-forward:
$ hg merge b
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg ci -Ammerge
Bogus fast-forward should fail:
$ hg merge b
abort: merging with a working directory ancestor has no effect
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