trial -u intermittent error: WindowsError: [Error 145] The directory is not empty: 'C:\\temp\\_trial_temp.lock'

New submission from ivank <[email protected]>:

C:\temp>python C:\Python26\Scripts\trial.py -u -e twisted.test.test_udp.UDPTestCase.testSendPackets

{{{
...successes elided...
-------------------------------------------------------------------------------
Ran 1 tests in 0.004s

PASSED (successes=1)
Test Pass 262
twisted.test.test_udp
  UDPTestCase
    testSendPackets ...                                                    [OK]

-------------------------------------------------------------------------------
Ran 1 tests in 0.005s

PASSED (successes=1)
Test Pass 263
twisted.test.test_udp
  UDPTestCase
    testSendPackets ...                                                    [OK]

-------------------------------------------------------------------------------
Ran 1 tests in 0.006s

PASSED (successes=1)
Test Pass 264
twisted.test.test_udp
  UDPTestCase
    testSendPackets ...                                                    [OK]

-------------------------------------------------------------------------------
Ran 1 tests in 0.006s

PASSED (successes=1)
Test Pass 265
twisted.test.test_udp
  UDPTestCase
    testSendPackets ...                                                    [OK]
Traceback (most recent call last):
  File "C:\Python26\Scripts\trial.py", line 22, in <module>
    run()
  File "C:\Python26\lib\site-packages\twisted\scripts\trial.py", line 359, in run
    test_result = trialRunner.runUntilFailure(suite)
  File "C:\Python26\lib\site-packages\twisted\trial\runner.py", line 893, in runUntilFailure
    result = self._runWithoutDecoration(test)
  File "C:\Python26\lib\site-packages\twisted\trial\runner.py", line 862, in _runWithoutDecoration
    self._tearDownTestdir(oldDir)
  File "C:\Python26\lib\site-packages\twisted\trial\runner.py", line 770, in _tearDownTestdir
    self._testDirLock.unlock()
  File "C:\Python26\lib\site-packages\twisted\python\lockfile.py", line 188, in unlock
    rmlink(self.name)
  File "C:\Python26\lib\site-packages\twisted\python\lockfile.py", line 82, in rmlink
    os.rmdir(filename)
WindowsError: [Error 145] The directory is not empty: 'C:\\temp\\_trial_temp.lock'
}}}

I did not start another process at this time. This happens on its own. After trial exits due to the exception, `_trial_temp\test.log`, `_trial_temp\test.log`, and a directory `_trial_temp.lock` remain.

It might be necessary to occupy CPU time to reproduce this bug, using something like OCCT or Prime95.

I tested with Server 2008 SP1, Python 2.6.2 32 bit, Twisted r27226 (built with VS2008).

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Type     : defect
Component: trial
Keywords : 
Priority : normal
Nosy     : 
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http://twistedmatrix.com/trac/ticket/3971