Mercurial > hg
view tests/test-atomictempfile.py @ 38676:3b072388ca78
scmutil: rewrite docstring for filecache
The old docstring was incorrect in that it said that subsequent
calls perform a stat() and refresh the object if things change.
This is not how things work: __get__ populates obj.__dict__[self.sname]
with the result of the decorated function and returns this value
without validation on subsequent calls, if available.
The correct usage of this type is kinda wonky. It would probably
benefit from a refactor. But I don't have time to do that right
now. But we can change the docstring so others aren't entrapped by
its lies (like I was when using repofilecache in a Mozilla extension).
Differential Revision: https://phab.mercurial-scm.org/D3943
author | Gregory Szorc <gregory.szorc@gmail.com> |
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date | Fri, 13 Jul 2018 14:20:12 -0700 |
parents | ffa3026d4196 |
children | 2372284d9457 |
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from __future__ import absolute_import import glob import os import shutil import stat import tempfile import unittest from mercurial import ( pycompat, util, ) atomictempfile = util.atomictempfile if pycompat.ispy3: xrange = range class testatomictempfile(unittest.TestCase): def setUp(self): self._testdir = tempfile.mkdtemp(b'atomictempfiletest') self._filename = os.path.join(self._testdir, b'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, b'.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, b'.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(b'.')) # if a programmer screws up and passes bad args to atomictempfile, they # get a plain ordinary TypeError, not infinite recursion def testoops(self): with self.assertRaises(TypeError): atomictempfile() # checkambig=True avoids ambiguity of timestamp def testcheckambig(self): def atomicwrite(checkambig): f = atomictempfile(self._filename, checkambig=checkambig) f.write(b'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[stat.ST_CTIME] != oldstat[stat.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 expected for j in xrange(repetition): atomicwrite(True) newstat = os.stat(self._filename) if oldstat[stat.ST_CTIME] != newstat[stat.ST_CTIME]: # timestamp ambiguity was naturally avoided while repetition continue # st_mtime should be advanced "repetition" times, because # all atomicwrite() occurred at same time (in sec) oldtime = (oldstat[stat.ST_MTIME] + repetition) & 0x7fffffff self.assertTrue(newstat[stat.ST_MTIME] == oldtime) # 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=b'rb') self.assertTrue(file.read(), b'foobar\n') file.discard() def testcontextmanagersuccess(self): """When the context closes, the file is closed""" with atomictempfile(b'foo') as f: self.assertFalse(os.path.isfile(b'foo')) f.write(b'argh\n') self.assertTrue(os.path.isfile(b'foo')) def testcontextmanagerfailure(self): """On exception, the file is discarded""" try: with atomictempfile(b'foo') as f: self.assertFalse(os.path.isfile(b'foo')) f.write(b'argh\n') raise ValueError except ValueError: pass self.assertFalse(os.path.isfile(b'foo')) if __name__ == '__main__': import silenttestrunner silenttestrunner.main(__name__)