hg: obtain lock when creating share from pooled repo (
issue5104)
There are race conditions between clients performing a shared clone
to pooled storage:
1) Clients race to create the new shared repo in the pool directory
2) 1 client is seeding the repo in the pool directory and another goes
to share it before it is fully cloned
We prevent these race conditions by obtaining a lock in the pool
directory that is derived from the name of the repo we will be
accessing.
To test this, a simple generic "lockdelay" extension has been added.
The extension inserts an optional, configurable delay before or after
lock acquisition. In the test, we delay 2 seconds after lock acquisition
in the first process and 1 second before lock acquisition in the 2nd
process. This means the first process has 1s to obtain the lock. There
is a race condition here. If we encounter it in the wild, we could
change the dummy extension to wait on the lock file to appear instead
of relying on timing. But that's more complicated. Let's see what
happens first.
"""test line matching with some failing examples and some which warn
run-test.t only checks positive matches and can not see warnings
(both by design)
"""
from __future__ import print_function
import os, re
# this is hack to make sure no escape characters are inserted into the output
if 'TERM' in os.environ:
del os.environ['TERM']
import doctest
run_tests = __import__('run-tests')
def prn(ex):
m = ex.args[0]
if isinstance(m, str):
print(m)
else:
print(m.decode('utf-8'))
def lm(expected, output):
r"""check if output matches expected
does it generally work?
>>> lm(b'H*e (glob)\n', b'Here\n')
True
fail on bad test data
>>> try: lm(b'a\n',b'a')
... except AssertionError as ex: print(ex)
missing newline
>>> try: lm(b'single backslash\n', b'single \backslash\n')
... except AssertionError as ex: prn(ex)
single backslash or unknown char
"""
assert (expected.endswith(b'\n')
and output.endswith(b'\n')), 'missing newline'
assert not re.search(br'[^ \w\\/\r\n()*?]', expected + output), \
b'single backslash or unknown char'
match = run_tests.TTest.linematch(expected, output)
if isinstance(match, str):
return 'special: ' + match
elif isinstance(match, bytes):
return 'special: ' + match.decode('utf-8')
else:
return bool(match) # do not return match object
def wintests():
r"""test matching like running on windows
enable windows matching on any os
>>> _osaltsep = os.altsep
>>> os.altsep = True
valid match on windows
>>> lm(b'g/a*/d (glob)\n', b'g\\abc/d\n')
True
direct matching, glob unnecessary
>>> lm(b'g/b (glob)\n', b'g/b\n')
'special: -glob'
missing glob
>>> lm(b'/g/c/d/fg\n', b'\\g\\c\\d/fg\n')
'special: +glob'
restore os.altsep
>>> os.altsep = _osaltsep
"""
pass
def otherostests():
r"""test matching like running on non-windows os
disable windows matching on any os
>>> _osaltsep = os.altsep
>>> os.altsep = False
backslash does not match slash
>>> lm(b'h/a* (glob)\n', b'h\\ab\n')
False
direct matching glob can not be recognized
>>> lm(b'h/b (glob)\n', b'h/b\n')
True
missing glob can not not be recognized
>>> lm(b'/h/c/df/g/\n', b'\\h/c\\df/g\\\n')
False
restore os.altsep
>>> os.altsep = _osaltsep
"""
pass
if __name__ == '__main__':
doctest.testmod()