from importlib import abc from importlib import machinery import inspect import unittest class InheritanceTests: """Test that the specified class is a subclass/superclass of the expected classes.""" subclasses = [] superclasses = [] def __init__(self, *args, **kwargs): super().__init__(*args, **kwargs) assert self.subclasses or self.superclasses, self.__class__ self.__test = getattr(abc, self.__class__.__name__) def test_subclasses(self): # Test that the expected subclasses inherit. for subclass in self.subclasses: self.assertTrue(issubclass(subclass, self.__test), "{0} is not a subclass of {1}".format(subclass, self.__test)) def test_superclasses(self): # Test that the class inherits from the expected superclasses. for superclass in self.superclasses: self.assertTrue(issubclass(self.__test, superclass), "{0} is not a superclass of {1}".format(superclass, self.__test)) class Finder(InheritanceTests, unittest.TestCase): subclasses = [machinery.BuiltinImporter, machinery.FrozenImporter, machinery.PathFinder] class Loader(InheritanceTests, unittest.TestCase): subclasses = [abc.PyLoader] class ResourceLoader(InheritanceTests, unittest.TestCase): superclasses = [abc.Loader] class InspectLoader(InheritanceTests, unittest.TestCase): superclasses = [abc.Loader] subclasses = [abc.PyLoader, machinery.BuiltinImporter, machinery.FrozenImporter] class PyLoader(InheritanceTests, unittest.TestCase): superclasses = [abc.Loader, abc.ResourceLoader, abc.InspectLoader] class PyPycLoader(InheritanceTests, unittest.TestCase): superclasses = [abc.PyLoader] def test_main(): from test.support import run_unittest classes = [] for class_ in globals().values(): if (inspect.isclass(class_) and issubclass(class_, unittest.TestCase) and issubclass(class_, InheritanceTests)): classes.append(class_) run_unittest(*classes) if __name__ == '__main__': test_main()