scmutil: add option to register summary callbacks as transaction validators
We have a list of summary callbacks which are run after the transaction is
closed to show what has changed and what not. This patch makes it possible to
register those callbacks as transaction validators so that we can show summary
before committing the transaction and prompt user to accept the changes.
The goal of this is to implement `pull --confirm`.
Differential Revision: https://phab.mercurial-scm.org/D8199
from __future__ import absolute_import
import copy
import errno
import tempfile
import types
import unittest
import silenttestrunner
from mercurial import (
encoding,
error,
lock,
vfs as vfsmod,
)
testlockname = b'testlock'
# work around http://bugs.python.org/issue1515
if types.MethodType not in copy._deepcopy_dispatch:
def _deepcopy_method(x, memo):
return type(x)(x.__func__, copy.deepcopy(x.__self__, memo), x.im_class)
copy._deepcopy_dispatch[types.MethodType] = _deepcopy_method
class lockwrapper(lock.lock):
def __init__(self, pidoffset, *args, **kwargs):
# lock.lock.__init__() calls lock(), so the pidoffset assignment needs
# to be earlier
self._pidoffset = pidoffset
super(lockwrapper, self).__init__(*args, **kwargs)
def _getpid(self):
return super(lockwrapper, self)._getpid() + self._pidoffset
class teststate(object):
def __init__(self, testcase, dir, pidoffset=0):
self._testcase = testcase
self._acquirecalled = False
self._releasecalled = False
self._postreleasecalled = False
self.vfs = vfsmod.vfs(dir, audit=False)
self._pidoffset = pidoffset
def makelock(self, *args, **kwargs):
l = lockwrapper(
self._pidoffset,
self.vfs,
testlockname,
releasefn=self.releasefn,
acquirefn=self.acquirefn,
*args,
**kwargs
)
l.postrelease.append(self.postreleasefn)
return l
def acquirefn(self):
self._acquirecalled = True
def releasefn(self):
self._releasecalled = True
def postreleasefn(self, success):
self._postreleasecalled = True
def assertacquirecalled(self, called):
self._testcase.assertEqual(
self._acquirecalled,
called,
'expected acquire to be %s but was actually %s'
% (self._tocalled(called), self._tocalled(self._acquirecalled),),
)
def resetacquirefn(self):
self._acquirecalled = False
def assertreleasecalled(self, called):
self._testcase.assertEqual(
self._releasecalled,
called,
'expected release to be %s but was actually %s'
% (self._tocalled(called), self._tocalled(self._releasecalled),),
)
def assertpostreleasecalled(self, called):
self._testcase.assertEqual(
self._postreleasecalled,
called,
'expected postrelease to be %s but was actually %s'
% (
self._tocalled(called),
self._tocalled(self._postreleasecalled),
),
)
def assertlockexists(self, exists):
actual = self.vfs.lexists(testlockname)
self._testcase.assertEqual(
actual,
exists,
'expected lock to %s but actually did %s'
% (self._toexists(exists), self._toexists(actual),),
)
def _tocalled(self, called):
if called:
return 'called'
else:
return 'not called'
def _toexists(self, exists):
if exists:
return 'exist'
else:
return 'not exist'
class testlock(unittest.TestCase):
def testlock(self):
state = teststate(self, tempfile.mkdtemp(dir=encoding.getcwd()))
lock = state.makelock()
state.assertacquirecalled(True)
lock.release()
state.assertreleasecalled(True)
state.assertpostreleasecalled(True)
state.assertlockexists(False)
def testrecursivelock(self):
state = teststate(self, tempfile.mkdtemp(dir=encoding.getcwd()))
lock = state.makelock()
state.assertacquirecalled(True)
state.resetacquirefn()
lock.lock()
# recursive lock should not call acquirefn again
state.assertacquirecalled(False)
lock.release() # brings lock refcount down from 2 to 1
state.assertreleasecalled(False)
state.assertpostreleasecalled(False)
state.assertlockexists(True)
lock.release() # releases the lock
state.assertreleasecalled(True)
state.assertpostreleasecalled(True)
state.assertlockexists(False)
def testlockfork(self):
state = teststate(self, tempfile.mkdtemp(dir=encoding.getcwd()))
lock = state.makelock()
state.assertacquirecalled(True)
# fake a fork
forklock = copy.copy(lock)
forklock._pidoffset = 1
forklock.release()
state.assertreleasecalled(False)
state.assertpostreleasecalled(False)
state.assertlockexists(True)
# release the actual lock
lock.release()
state.assertreleasecalled(True)
state.assertpostreleasecalled(True)
state.assertlockexists(False)
def testinheritlock(self):
d = tempfile.mkdtemp(dir=encoding.getcwd())
parentstate = teststate(self, d)
parentlock = parentstate.makelock()
parentstate.assertacquirecalled(True)
# set up lock inheritance
with parentlock.inherit() as lockname:
parentstate.assertreleasecalled(True)
parentstate.assertpostreleasecalled(False)
parentstate.assertlockexists(True)
childstate = teststate(self, d, pidoffset=1)
childlock = childstate.makelock(parentlock=lockname)
childstate.assertacquirecalled(True)
childlock.release()
childstate.assertreleasecalled(True)
childstate.assertpostreleasecalled(False)
childstate.assertlockexists(True)
parentstate.resetacquirefn()
parentstate.assertacquirecalled(True)
parentlock.release()
parentstate.assertreleasecalled(True)
parentstate.assertpostreleasecalled(True)
parentstate.assertlockexists(False)
def testmultilock(self):
d = tempfile.mkdtemp(dir=encoding.getcwd())
state0 = teststate(self, d)
lock0 = state0.makelock()
state0.assertacquirecalled(True)
with lock0.inherit() as lock0name:
state0.assertreleasecalled(True)
state0.assertpostreleasecalled(False)
state0.assertlockexists(True)
state1 = teststate(self, d, pidoffset=1)
lock1 = state1.makelock(parentlock=lock0name)
state1.assertacquirecalled(True)
# from within lock1, acquire another lock
with lock1.inherit() as lock1name:
# since the file on disk is lock0's this should have the same
# name
self.assertEqual(lock0name, lock1name)
state2 = teststate(self, d, pidoffset=2)
lock2 = state2.makelock(parentlock=lock1name)
state2.assertacquirecalled(True)
lock2.release()
state2.assertreleasecalled(True)
state2.assertpostreleasecalled(False)
state2.assertlockexists(True)
state1.resetacquirefn()
state1.assertacquirecalled(True)
lock1.release()
state1.assertreleasecalled(True)
state1.assertpostreleasecalled(False)
state1.assertlockexists(True)
lock0.release()
def testinheritlockfork(self):
d = tempfile.mkdtemp(dir=encoding.getcwd())
parentstate = teststate(self, d)
parentlock = parentstate.makelock()
parentstate.assertacquirecalled(True)
# set up lock inheritance
with parentlock.inherit() as lockname:
childstate = teststate(self, d, pidoffset=1)
childlock = childstate.makelock(parentlock=lockname)
childstate.assertacquirecalled(True)
# fork the child lock
forkchildlock = copy.copy(childlock)
forkchildlock._pidoffset += 1
forkchildlock.release()
childstate.assertreleasecalled(False)
childstate.assertpostreleasecalled(False)
childstate.assertlockexists(True)
# release the child lock
childlock.release()
childstate.assertreleasecalled(True)
childstate.assertpostreleasecalled(False)
childstate.assertlockexists(True)
parentlock.release()
def testinheritcheck(self):
d = tempfile.mkdtemp(dir=encoding.getcwd())
state = teststate(self, d)
def check():
raise error.LockInheritanceContractViolation('check failed')
lock = state.makelock(inheritchecker=check)
state.assertacquirecalled(True)
with self.assertRaises(error.LockInheritanceContractViolation):
with lock.inherit():
pass
lock.release()
def testfrequentlockunlock(self):
"""This tests whether lock acquisition fails as expected, even if
(1) lock can't be acquired (makelock fails by EEXIST), and
(2) locker info can't be read in (readlock fails by ENOENT) while
retrying 5 times.
"""
d = tempfile.mkdtemp(dir=encoding.getcwd())
state = teststate(self, d)
def emulatefrequentlock(*args):
raise OSError(errno.EEXIST, "File exists")
def emulatefrequentunlock(*args):
raise OSError(errno.ENOENT, "No such file or directory")
state.vfs.makelock = emulatefrequentlock
state.vfs.readlock = emulatefrequentunlock
try:
state.makelock(timeout=0)
self.fail("unexpected lock acquisition")
except error.LockHeld as why:
self.assertTrue(why.errno == errno.ETIMEDOUT)
self.assertTrue(why.locker == b"")
state.assertlockexists(False)
if __name__ == '__main__':
silenttestrunner.main(__name__)