py3: use pycompat.bytestr() instead of pycompat.sysstr() pycompat.sysstr() doesn’t work because it doesn’t accept arguments of type `type` and returns a unicode object on Python3, while the format string wants a bytes-like object.

lock: fix race in lock-breaking code With low frequency, I see hg pulls fail with output like: abort: no such file or directory: .hg/store/lock I think what happens is, in lock.py, in: def _testlock(self, locker): if not self._lockshouldbebroken(locker): return locker # if locker dead, break lock. must do this with another lock # held, or can race and break valid lock. try: with lock(self.vfs, self.f + b'.break', timeout=0): self.vfs.unlink(self.f) except error.LockError: return locker if a lock is breakable on disk, and two hg processes concurrently get to the "if locker dead" comment, a possible interleaving is: process1 finishes executing the function and then process2 finishes executing the function. If that happens, process2 will either get ENOENT in self.vfs.unlink (resulting in the spurious failure above), or break a valid lock and potentially cause repository corruption. The fix is simple enough: make sure the lock is breakable _inside_ the critical section, because only then can we know that no other process can invalidate our knowledge on the lock on disk. I don't think there are tests for this. I've tested this manually with: diff --git a/mercurial/lock.py b/mercurial/lock.py --- a/mercurial/lock.py +++ b/mercurial/lock.py @@ -351,6 +351,8 @@ class lock(object): if not self._lockshouldbebroken(locker): return locker + import random + time.sleep(1. + random.random()) # if locker dead, break lock. must do this with another lock # held, or can race and break valid lock. try: @@ -358,6 +360,7 @@ class lock(object): self.vfs.unlink(self.f) except error.LockError: return locker + time.sleep(1) def testlock(self): """return id of locker if lock is valid, else None. and I see this change of behavior before/after this commit: $ $hg init repo $ cd repo $ ln -s $HOSTNAME/effffffc:987654321 .hg/wlock $ touch a $ $hg commit -Am_ & $hg commit -Am _; wait -abort: No such file or directory: '/tmp/repo/.hg/wlock' adding a +warning: ignoring unknown working parent 679a8959a8ca! +nothing changed Differential Revision: https://phab.mercurial-scm.org/D7199

lock: refactor in preparation for next commit Differential Revision: https://phab.mercurial-scm.org/D7198

extensions: suppress a pytype failure due to a typeshed bug Bug filed upstream, suppress the failure here so we can move on. Differential Revision: https://phab.mercurial-scm.org/D7410

dispatch: add some assertions to give pytype a helping hand Differential Revision: https://phab.mercurial-scm.org/D7409

extensions: hide two confusing import statements from pytype Differential Revision: https://phab.mercurial-scm.org/D7408

debugcommands: add assertions to convince pytype peer is not None This function is moderately annoyingly defined, and peer is set up iff we're not in raw-proto mode. That's fine, but it confuses pytype. Adding these assertions is a low-overhead way to convince pytype we're doing reasonable things. Differential Revision: https://phab.mercurial-scm.org/D7407

debugcommands: suppress import errors for pytype Differential Revision: https://phab.mercurial-scm.org/D7385

state: add a pytype annotation Differential Revision: https://phab.mercurial-scm.org/D7383

logcmdutil: add a type annotation This wasn't actually required in the end, as there was a real bug found by pytype, but the annotation helped me figure that out. We can drop this patch if that's the preference. Differential Revision: https://phab.mercurial-scm.org/D7382