Chris Jerdonek added the comment: Okay, I think I understand the issue better now. The threading._dangling warning happens because when leaving the saved_test_environment context manager in regrtest:
http://hg.python.org/cpython/file/fcdb35b114ab/Lib/test/regrtest.py#l1271 the context manager finds threads still in threading._dangling that weren't there at the beginning. I think the threads are still in there because the "tests" variable in the code linked to above is holding references to those threads (which isn't surprising given what test_concurrent_futures.py tests). So this is preventing the threads (which are in a WeakSet) from being garbage collected. On my machine, severing those references before leaving the context manager solves the problem. You can do this by adding "test = 0" after the test_runner() line, or defining "tests" inside an inner function as follows: if test_runner is None: def test_runner(): tests = unittest.TestLoader().loadTestsFromModule(the_module) support.run_unittest(tests) test_runner() To be completely sure, we may also need to do something to ensure that the threads are garbage collected before leaving the context manager. Currently, an explicit call to support.gc_collect() happens in threading_cleanup() (which is in turn called by reap_threads(), etc): http://hg.python.org/cpython/file/fcdb35b114ab/Lib/test/support.py#l1665 But I'm not sure if that's late enough in the process to guarantee garbage collection of those threads with the test_runner() change above (since the tests list might still be defined). ---------- _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue16968> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
