#!/usr/bin/python import unittest from PySide import QtCore class Lock(QtCore.QMutex): def tryLock(self,timeoutt=10): return QtCore.QMutex.tryLock(self,timeoutt) class TestBug(unittest.TestCase): def testCase(self): l = Lock() l.tryLock() # this cause a assertion if __name__ == '__main__': unittest.main()