largefiles: correctly handle dirstate status when rebasing
When rebasing, we need to trust that the standins are always correct. The
rebase operation updates the standins according to the changeset it is
rebasing. We need to make the largefiles in the working copy match. If we
don't make them match, then they get accidentally reverted, either during
the rebase or during the next commit after the rebase.
This worked previously only becuase we were relying on the behavior that
largefiles with a changed standin, but unchanged contents, never showed up in
the list of modified largefiles. Unfortunately, pre-commit hooks can get
an incorrect status this way, and it also results in extra execution of code.
The solution is to simply trust the standins when we are about to commit a
rebased changeset, and politely ask updatelfiles() to pull the new contents
down. In this case, updatelfiles() will also mark any files it has pulled
down as dirty in the lfdirstate so that pre-commit hooks will get correct
status output.
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
(branches are permanent and global, did you want a bookmark?)
$ 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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