name : testing_refleaks.py # Protocol Buffers - Google's data interchange format # Copyright 2008 Google Inc. All rights reserved. # https://developers.google.com/protocol-buffers/ # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are # met: # # * Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # * Redistributions in binary form must reproduce the above # copyright notice, this list of conditions and the following disclaimer # in the documentation and/or other materials provided with the # distribution. # * Neither the name of Google Inc. nor the names of its # contributors may be used to endorse or promote products derived from # this software without specific prior written permission. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR # A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. """A subclass of unittest.TestCase which checks for reference leaks. To use: - Use testing_refleak.BaseTestCase instead of unittest.TestCase - Configure and compile Python with --with-pydebug If sys.gettotalrefcount() is not available (because Python was built without the Py_DEBUG option), then this module is a no-op and tests will run normally. """ import gc import sys try: import copy_reg as copyreg #PY26 except ImportError: import copyreg try: import unittest2 as unittest #PY26 except ImportError: import unittest class LocalTestResult(unittest.TestResult): """A TestResult which forwards events to a parent object, except for Skips.""" def __init__(self, parent_result): unittest.TestResult.__init__(self) self.parent_result = parent_result def addError(self, test, error): self.parent_result.addError(test, error) def addFailure(self, test, error): self.parent_result.addFailure(test, error) def addSkip(self, test, reason): pass class ReferenceLeakCheckerTestCase(unittest.TestCase): """A TestCase which runs tests multiple times, collecting reference counts.""" NB_RUNS = 3 def run(self, result=None): # python_message.py registers all Message classes to some pickle global # registry, which makes the classes immortal. # We save a copy of this registry, and reset it before we could references. self._saved_pickle_registry = copyreg.dispatch_table.copy() # Run the test twice, to warm up the instance attributes. super(ReferenceLeakCheckerTestCase, self).run(result=result) super(ReferenceLeakCheckerTestCase, self).run(result=result) oldrefcount = 0 local_result = LocalTestResult(result) refcount_deltas = [] for _ in range(self.NB_RUNS): oldrefcount = self._getRefcounts() super(ReferenceLeakCheckerTestCase, self).run(result=local_result) newrefcount = self._getRefcounts() refcount_deltas.append(newrefcount - oldrefcount) print(refcount_deltas, self) try: self.assertEqual(refcount_deltas, [0] * self.NB_RUNS) except Exception: # pylint: disable=broad-except result.addError(self, sys.exc_info()) def _getRefcounts(self): copyreg.dispatch_table.clear() copyreg.dispatch_table.update(self._saved_pickle_registry) # It is sometimes necessary to gc.collect() multiple times, to ensure # that all objects can be collected. gc.collect() gc.collect() gc.collect() return sys.gettotalrefcount() if hasattr(sys, 'gettotalrefcount'): BaseTestCase = ReferenceLeakCheckerTestCase SkipReferenceLeakChecker = unittest.skip else: # When PyDEBUG is not enabled, run the tests normally. BaseTestCase = unittest.TestCase def SkipReferenceLeakChecker(reason): del reason # Don't skip, so don't need a reason. def Same(func): return func return Same