pycompat: make pycompat demandimport friendly
pycompat.py includes hack to import modules whose names are changed in Python 3.
We use try-except to load module according to the version of python. But this
method forces us to import the modules to raise an ImportError and hence making
it demandimport unfriendly.
This patch changes the try-except blocks to a single if-else block. To avoid
test-check-pyflakes.t complain about unused imports, pycompat.py is excluded
from the test.
from __future__ import absolute_import
import glob
import os
import shutil
import tempfile
import unittest
from mercurial import (
util,
)
atomictempfile = util.atomictempfile
class testatomictempfile(unittest.TestCase):
def setUp(self):
self._testdir = tempfile.mkdtemp('atomictempfiletest')
self._filename = os.path.join(self._testdir, 'testfilename')
def tearDown(self):
shutil.rmtree(self._testdir, True)
def testsimple(self):
file = atomictempfile(self._filename)
self.assertFalse(os.path.isfile(self._filename))
tempfilename = file._tempname
self.assertTrue(tempfilename in glob.glob(
os.path.join(self._testdir, '.testfilename-*')))
file.write(b'argh\n')
file.close()
self.assertTrue(os.path.isfile(self._filename))
self.assertTrue(tempfilename not in glob.glob(
os.path.join(self._testdir, '.testfilename-*')))
# discard() removes the temp file without making the write permanent
def testdiscard(self):
file = atomictempfile(self._filename)
(dir, basename) = os.path.split(file._tempname)
file.write(b'yo\n')
file.discard()
self.assertFalse(os.path.isfile(self._filename))
self.assertTrue(basename not in os.listdir('.'))
# if a programmer screws up and passes bad args to atomictempfile, they
# get a plain ordinary TypeError, not infinite recursion
def testoops(self):
self.assertRaises(TypeError, atomictempfile)
# checkambig=True avoids ambiguity of timestamp
def testcheckambig(self):
def atomicwrite(checkambig):
f = atomictempfile(self._filename, checkambig=checkambig)
f.write('FOO')
f.close()
# try some times, because reproduction of ambiguity depends on
# "filesystem time"
for i in xrange(5):
atomicwrite(False)
oldstat = os.stat(self._filename)
if oldstat.st_ctime != oldstat.st_mtime:
# subsequent changing never causes ambiguity
continue
repetition = 3
# repeat atomic write with checkambig=True, to examine
# whether st_mtime is advanced multiple times as expecetd
for j in xrange(repetition):
atomicwrite(True)
newstat = os.stat(self._filename)
if oldstat.st_ctime != newstat.st_ctime:
# timestamp ambiguity was naturally avoided while repetition
continue
# st_mtime should be advanced "repetition" times, because
# all atomicwrite() occured at same time (in sec)
self.assertTrue(newstat.st_mtime ==
((oldstat.st_mtime + repetition) & 0x7fffffff))
# no more examination is needed, if assumption above is true
break
else:
# This platform seems too slow to examine anti-ambiguity
# of file timestamp (or test happened to be executed at
# bad timing). Exit silently in this case, because running
# on other faster platforms can detect problems
pass
def testread(self):
with open(self._filename, 'wb') as f:
f.write(b'foobar\n')
file = atomictempfile(self._filename, mode='rb')
self.assertTrue(file.read(), b'foobar\n')
file.discard()
def testcontextmanagersuccess(self):
"""When the context closes, the file is closed"""
with atomictempfile('foo') as f:
self.assertFalse(os.path.isfile('foo'))
f.write(b'argh\n')
self.assertTrue(os.path.isfile('foo'))
def testcontextmanagerfailure(self):
"""On exception, the file is discarded"""
try:
with atomictempfile('foo') as f:
self.assertFalse(os.path.isfile('foo'))
f.write(b'argh\n')
raise ValueError
except ValueError:
pass
self.assertFalse(os.path.isfile('foo'))
if __name__ == '__main__':
import silenttestrunner
silenttestrunner.main(__name__)