Python中unittest用法实例
投稿:shichen2014
本文实例讲述了Python中unittest的用法,分享给大家供大家参考。具体用法分析如下:
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:
① setup():每个测试函数运行前运行
② teardown():每个测试函数运行完后执行
③ setUpClass():必须使用@classmethod 装饰器,所有test运行前运行一次
④ 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 random import unittest class 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()
3.运行方式:在命令行直接运行这个runtest.py
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:
① @unittest.skip(reason):无条件跳过测试,reason描述为什么跳过测试
② @unittest.skipif(conditition,reason):condititon为true时跳过测试
③ @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 decorrator def 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
希望本文所述对大家Python程序设计的学习有所帮助。