revert: distinguish between "check" and "backup" strategy
"check" behaves as backup did before. We check if the current file differs
from destination and we create a backup if it does. This is used for untracked
files that will be overwritten by formerly-deleted files. We have to do the manual
check since no status output can provide the content comparison.
"backup" is now doing unconditional backup. This can be used for files seen as
modified compared to both the target and the working directory. In such a case, we
know that the file differs from target without actually comparing any content.
This new "backup" strategy will be especially useful in the case of files added
between the target and the working directory -parent- with additional modifications
in the working directory -itself-. In that case we know we need to back it up, but we
cannot run the content check as the files does not exists in target.
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 ..