# 7. 各种断言方法




### 背景

unittest支持各种断言方法。

### 断言列表

[官方文档](https://docs.python.org/2/library/unittest.html)

|方法|检查点|
|---|---|
|assertEqual(a, b)|a == b|
|assertNotEqual(a, b)|a != b|
|assertTrue(x)|bool(x) is True|
|assertFalse(x)|bool(x) is False|
|assertIs(a, b)|a is b|
|assertIsNot(a, b)|a is not b|
|assertIsNone(x)|x is None|
|assertIsNotNone(x)|x is not None|
|assertIn(a, b)|a in b|
|assertNotIn(a, b)|a not in b|
|assertIsInstance(a, b)|isinstance(a, b)|
|assertNotIsInstance(a, b)|not isinstance(a, b)|
|assertRaises(exc, fun, *args, **kwds)|	fun(*args, **kwds) raises exc|
|assertRaisesRegexp(exc, r, fun, *args, **kwds)|fun(*args, **kwds) raises exc and the message matches regex r|
|assertAlmostEqual(a, b)|round(a-b, 7) == 0|
|assertNotAlmostEqual(a, b)|round(a-b, 7) != 0|
|assertGreater(a, b)|a > b	2.7|
|assertGreaterEqual(a, b)|a >= b|
|assertLess(a, b)|a < b|
|assertLessEqual(a, b)|a <= b|
|assertRegexpMatches(s, r)|r.search(s)|
|assertNotRegexpMatches(s, r)|not r.search(s)|
|assertItemsEqual(a, b)|sorted(a) == sorted(b) 也支持unhashable对象|
|assertDictContainsSubset(a, b)|a里面所有的键值对都在b中存在|

### 自己动手

大家可以自己动手亲自尝试使用这些断言方法。




原始封面

![课程图片](https://images.unsplash.com/photo-1501555790667-ba7ea28b4cea?w=300)