remotefilelog: reduce probability of race-condition in remotefilelog tests
ca1014ad3de4 introduced a new parameter `ensurestart` to speed up
remotefilelog background processes start. Unfortunately it seems to have
increased the possibility of race-conditions in remotefilelog tests testing
those background processes.
With `ensurestart=False`, it seems that it's more probable to enter in a race
condition with `debugwaitonprefetch` and `debugwaitonrepack` in remotefilelog
background tests. Our CI seems to have a high probability of triggering this
race condition so make it configurable to ensure tests are stable.
Differential Revision: https://phab.mercurial-scm.org/D6772
# unit tests for mercuril.util utilities
from __future__ import absolute_import
import contextlib
import itertools
import unittest
from mercurial import pycompat, util, utils
@contextlib.contextmanager
def mocktimer(incr=0.1, *additional_targets):
"""Replaces util.timer and additional_targets with a mock
The timer starts at 0. On each call the time incremented by the value
of incr. If incr is an iterable, then the time is incremented by the
next value from that iterable, looping in a cycle when reaching the end.
additional_targets must be a sequence of (object, attribute_name) tuples;
the mock is set with setattr(object, attribute_name, mock).
"""
time = [0]
try:
incr = itertools.cycle(incr)
except TypeError:
incr = itertools.repeat(incr)
def timer():
time[0] += next(incr)
return time[0]
# record original values
orig = util.timer
additional_origs = [(o, a, getattr(o, a)) for o, a in additional_targets]
# mock out targets
util.timer = timer
for obj, attr in additional_targets:
setattr(obj, attr, timer)
try:
yield
finally:
# restore originals
util.timer = orig
for args in additional_origs:
setattr(*args)
# attr.s default factory for util.timedstats.start binds the timer we
# need to mock out.
_start_default = (util.timedcmstats.start.default, 'factory')
@contextlib.contextmanager
def capturestderr():
"""Replace utils.procutil.stderr with a pycompat.bytesio instance
The instance is made available as the return value of __enter__.
This contextmanager is reentrant.
"""
orig = utils.procutil.stderr
utils.procutil.stderr = pycompat.bytesio()
try:
yield utils.procutil.stderr
finally:
utils.procutil.stderr = orig
class timedtests(unittest.TestCase):
def testtimedcmstatsstr(self):
stats = util.timedcmstats()
self.assertEqual(str(stats), '<unknown>')
self.assertEqual(bytes(stats), b'<unknown>')
stats.elapsed = 12.34
self.assertEqual(str(stats), pycompat.sysstr(util.timecount(12.34)))
self.assertEqual(bytes(stats), util.timecount(12.34))
def testtimedcmcleanexit(self):
# timestamps 1, 4, elapsed time of 4 - 1 = 3
with mocktimer([1, 3], _start_default):
with util.timedcm('pass') as stats:
# actual context doesn't matter
pass
self.assertEqual(stats.start, 1)
self.assertEqual(stats.elapsed, 3)
self.assertEqual(stats.level, 1)
def testtimedcmnested(self):
# timestamps 1, 3, 6, 10, elapsed times of 6 - 3 = 3 and 10 - 1 = 9
with mocktimer([1, 2, 3, 4], _start_default):
with util.timedcm('outer') as outer_stats:
with util.timedcm('inner') as inner_stats:
# actual context doesn't matter
pass
self.assertEqual(outer_stats.start, 1)
self.assertEqual(outer_stats.elapsed, 9)
self.assertEqual(outer_stats.level, 1)
self.assertEqual(inner_stats.start, 3)
self.assertEqual(inner_stats.elapsed, 3)
self.assertEqual(inner_stats.level, 2)
def testtimedcmexception(self):
# timestamps 1, 4, elapsed time of 4 - 1 = 3
with mocktimer([1, 3], _start_default):
try:
with util.timedcm('exceptional') as stats:
raise ValueError()
except ValueError:
pass
self.assertEqual(stats.start, 1)
self.assertEqual(stats.elapsed, 3)
self.assertEqual(stats.level, 1)
def testtimeddecorator(self):
@util.timed
def testfunc(callcount=1):
callcount -= 1
if callcount:
testfunc(callcount)
# timestamps 1, 2, 3, 4, elapsed time of 3 - 2 = 1 and 4 - 1 = 3
with mocktimer(1, _start_default):
with capturestderr() as out:
testfunc(2)
self.assertEqual(out.getvalue(), (
b' testfunc: 1.000 s\n'
b' testfunc: 3.000 s\n'
))
if __name__ == '__main__':
import silenttestrunner
silenttestrunner.main(__name__)