contrib/lock-checker.py

test-merge-tools: fix flaky test by avoiding debugsetparents

debugsetparents is a debug command and does not provide the same
guarantees as non-debug commands do. In particular, when the user sets
a different parent, any clean files will remain clean in the dirstate
even though the new parent might have a different version of the file
(so it should appear modified compared to the new parent). Let's
instead achieve the same effect by updating to the new parent and
reverting the contents back to what they were.

This fix can be tested by passing '--config
debug.dirstate.delaywrite=2' to the 'hg update' command in the
beforemerge().

"""Extension to verify locks are obtained in the required places.

This works by wrapping functions that should be surrounded by a lock
and asserting the lock is held. Missing locks are called out with a
traceback printed to stderr.

This currently only checks store locks, not working copy locks.
"""
import os
from mercurial import util

def _checklock(repo):
    l = repo._lockref and repo._lockref()
    if l is None or not l.held:
        util.debugstacktrace('missing lock', skip=1)

def reposetup(ui, repo):
    orig = repo.__class__
    class lockcheckrepo(repo.__class__):
        def _writejournal(self, *args, **kwargs):
            _checklock(self)
            return orig._writejournal(self, *args, **kwargs)

        def transaction(self, *args, **kwargs):
            _checklock(self)
            return orig.transaction(self, *args, **kwargs)

        # TODO(durin42): kiilerix had a commented-out lock check in
        # _writebranchcache and _writerequirements

        def _tag(self, *args, **kwargs):
            _checklock(self)
            return orig._tag(self, *args, **kwargs)

        def write(self, *args, **kwargs):
            assert os.path.lexists(self._join('.hg/wlock'))
            return orig.write(self, *args, **kwargs)

    repo.__class__ = lockcheckrepo