view tests/test-lock.py @ 36743:d031609b3cb7 stable

changegroup: do not delta lfs revisions

There is no way to distinguish whether a delta base is LFS or non-LFS.

If the delta is against LFS rawtext, and the client trying to apply it has
the base revision stored as fulltext, the delta (aka. bundle) will fail to
apply.

This patch forbids using delta for LFS revisions in changegroup so bad
deltas won't be transmitted.

Note: this does not solve the problem entirely. It solves LFS delta applying
to non-LFS base. But the other direction: non-LFS delta applying to LFS base
is not solved yet.

Differential Revision: https://phab.mercurial-scm.org/D2067

from __future__ import absolute_import

import copy
import errno
import os
import silenttestrunner
import tempfile
import types
import unittest

from mercurial import (
    error,
    lock,
    vfs as vfsmod,
)

testlockname = '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):
        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=os.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=os.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=os.getcwd()))
        lock = state.makelock()
        state.assertacquirecalled(True)

        # fake a fork
        forklock = copy.deepcopy(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=os.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=os.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=os.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.deepcopy(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=os.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=os.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 == "")
            state.assertlockexists(False)

if __name__ == '__main__':
    silenttestrunner.main(__name__)