1. unittest module包含了编写运行unittest的功能，自定义的test class都要集成unitest.TestCase类，test method要以test开头，运行顺序根据test method的名字排序，特殊方法:
   • setup():每个测试函数运行前运行
   • teardown():每个测试函数运行完后执行
   • setUpClass():必须使用@classmethod 装饰器,所有test运行前运行一次
   • tearDownClass():必须使用@classmethod装饰器,所有test运行完后运行一次
2. 示例代码:

   #文件名runtest.py
   import randomimport unittestclass TestSequenceFunctions(unittest.TestCase):    def setUp(self):        self.seq = list(range(10))    def test_shuffle(self):        # make sure the shuffled sequence does not lose any elements        random.shuffle(self.seq)        self.seq.sort()        self.assertEqual(self.seq, list(range(10)))        # should raise an exception for an immutable sequence        self.assertRaises(TypeError, random.shuffle, (1,2,3))    def test_choice(self):        element = random.choice(self.seq)        self.assertTrue(element in self.seq)    def test_sample(self):        with self.assertRaises(ValueError):            random.sample(self.seq, 20)        for element in random.sample(self.seq, 5):            self.assertTrue(element in self.seq)if __name__ == ‘__main__‘:    unittest.main()

   运行方式:在命令行直接运行这个runtest.py
3. 可以使用unitest.skip装饰器族跳过test method或者test class,这些装饰器包括:
• @unittest.skip(reason):无条件跳过测试，reason描述为什么跳过测试
• @unittest.skipif(conditition,reason):condititon为true时跳过测试
• @unittest.skipunless(condition,reason):condition不是true时跳过测试
• 可以自定义skip decorator

  #这是一个自定义的skip decorratordef skipUnlessHasattr(obj, attr):    if hasattr(obj, attr):        return lambda func: func    return unittest.skip("{!r} doesn‘t have {!r}".format(obj, attr))

• skip decorator示例代码:

  class MyTestCase(unittest.TestCase):    @unittest.skip("demonstrating skipping")    def test_nothing(self):        self.fail("shouldn‘t happen")    @unittest.skipIf(mylib.__version__ < (1, 3),                     "not supported in this library version")    def test_format(self):        # Tests that work for only a certain version of the library.        pass    @unittest.skipUnless(sys.platform.startswith("win"), "requires Windows")    def test_windows_support(self):        # windows specific testing code        pass@unittest.skip("showing class skipping")class MySkippedTestCase(unittest.TestCase):    def test_not_run(self):        pass

4. expected failure:使用@unittest.expectedFailure装饰器，如果test失败了，这个test不计入失败的case数目

Python unittest