phases: move root phase assignment to it's own function
This moves the initial root phase assignment to it's own function. Future
patches which make phase calculations lazy will use this function to pre-fill
certain phases which can be deduced from the roots.
Corrupt an hg repo with a pull started during an aborted commit
Create two repos, so that one of them can pull from the other one.
$ hg init source
$ cd source
$ touch foo
$ hg add foo
$ hg ci -m 'add foo'
$ hg clone . ../corrupted
updating to branch default
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ echo >> foo
$ hg ci -m 'change foo'
Add a hook to wait 5 seconds and then abort the commit
$ cd ../corrupted
$ echo "[hooks]" >> .hg/hgrc
$ echo "pretxncommit = sh -c 'sleep 5; exit 1'" >> .hg/hgrc
start a commit...
$ touch bar
$ hg add bar
$ hg ci -m 'add bar' &
... and start a pull while the commit is still running
$ sleep 1
$ hg pull ../source 2>/dev/null
pulling from ../source
transaction abort!
rollback completed
abort: pretxncommit hook exited with status 1
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files
(run 'hg update' to get a working copy)
see what happened
$ wait
$ hg verify
checking changesets
checking manifests
crosschecking files in changesets and manifests
checking files
1 files, 2 changesets, 2 total revisions
$ cd ..