一、摘要

單元測試裡很重要的一個部分就是斷言，unittest為我們提供了很多斷言方法

• assertEqual(a, b, msg=None)斷言 a == b
• assertNotEqual(a, b, msg=None)斷言  a != b
• assertTrue(expr, msg=None)斷言  bool(expr) is True
• assertFalse(expr, msg=None)斷言  bool(expr) is False
• assertIs(a, b, msg=None)斷言  a is b
• assertIsNot(a, b, msg=None)斷言  a is not b
• assertIsNone(expr, msg=None)斷言  expr is None
• assertIsNotNone(expr, msg=None)斷言  expr is not None
• assertIn(a, b, msg=None)斷言  a in b
• assertNotIn(a, b, msg=None)斷言  a not in b
• assertIsInstance(obj, cls, msg=None)斷言 obj  is cls instance
• assertNotIsInstance(obj, cls, msg=None)斷言 obj is not cls instance
• assertRaises(exc, fun, *args, **kwds)斷言  fun(*args, **kwds) raises exc 否則丟擲斷言異常
• assertRaisesRegex(exc, r, fun, *args, **kwds) 斷言  fun(*args, **kwds) raises exc and the exc message matches regex r 否則丟擲斷言異常

二、程式碼例項

# encoding = utf-8
import unittest
import random


#  被測試類
class
 
 ToBeTest(object):
    @classmethod
    def sum(cls, a, b):
        return a + b

    @classmethod
    def div(cls, a, b):
        return a/b

    @classmethod
    def return_none(cls):
        return None


#  單元測試類
class TestToBeTest(unittest.TestCase):

    # assertEqual()方法例項
    def test_assertequal(self):
        try:
            a, b = 100, 200
            sum = 300
            # 斷言a+b等於sum
            self.assertEqual(a + b, sum, '斷言失敗，%s+%s != %s ' %(a, b, sum))
        except AssertionError as e:
            print(e)

    # assertNotEqual()方法例項
    def test_assertnotequal(self):
        try:
            a, b = 100, 200
            res = -1000
            # 斷言a-b不等於res
            self.assertNotEqual(a - b, res, '斷言失敗，%s-%s != %s ' %(a, b, res))
        except AssertionError as e:
            print(e)

    # assertTure()方法例項
    def test_asserttrue(self):
        list1 = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
        list2 = [10, 9, 8, 7, 6, 5, 4, 3, 2, 1]
        list3 = list1[::-1]
        print(list3)
        try:
            # 斷言表示式為真
            self.assertTrue(list3 == list2, "表示式為假")
        except AssertionError as e:
            print(e)

    # assertFalse()方法例項
    def test_assertfalse(self):
        list1 = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
        list2 = [10, 9, 8, 7, 6, 5, 4, 3, 2, 1]
        list3 = list1[::-1]
        try:
            #  斷言表示式為假
            self.assertFalse(list3 == list1, "表示式為真")
        except AssertionError as e:
            print(e)

    # assertIs()方法例項
    def test_assertis(self):
        list1 = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
        list2 = list1
        try:
            # 斷言list2和list1屬於同一個物件
            self.assertIs(list1, list2, "%s 與 %s 不屬於同一物件" % (list1, list2))
        except AssertionError as e:
            print(e)

    # assertIsNot()方法例項
    def test_assertisnot(self):
        list1 = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
        list2 = [10, 9, 8, 7, 6, 5, 4, 3, 2, 1]
        try:
            # 斷言list2和list1不屬於同一個物件
            self.assertIsNot(list2, list1, "%s 與 %s 屬於同一物件" % (list1, list2))
        except AssertionError as e:
            print(e)

    # assertIsNone()方法例項
    def test_assertisnone(self):
        try:
            results = ToBeTest.return_none()
            # 斷言表示式結果是none
            self.assertIsNone(results, "is not none")
        except AssertionError as e:
            print(e)

    # assertIsNotNone()方法例項
    def test_assertisnotnone(self):
        try:
            results = ToBeTest.sum(4, 5)
            # 斷言表示式結果不是none
            self.assertIsNotNone(results, "is none")
        except AssertionError as e:
            print(e)

    # assertIn()方法例項
    def test_assertin(self):
        try:
            str1 = "this is unit test demo"
            str2 = "demo"
            # 斷言str2包含在str1中
            self.assertIn(str2, str1, "%s 不被包含在 %s中" %(str2, str1))
        except AssertionError as e:
            print(e)

    # assertNotIn()方法例項
    def test_assertnotin(self):
        try:
            str1 = "this is unit test demo"
            str2 = "ABC"
            # 斷言str2不包含在str1中
            self.assertNotIn(str2, str1, "%s 包含在 %s 中" % (str2, str1))
        except AssertionError as e:
            print(e)

    # assertIsInstance()方法例項
    def test_assertisinstance(self):
        try:
            o = ToBeTest
            k = object
            # 斷言測試物件o是k的型別
            self.assertIsInstance(o, k, "%s的型別不是%s" % (o, k))
        except AssertionError as e:
            print(e)

    # assertNotIsInstance()方法例項
    def test_assertnotisinstance(self):
        try:
            o = ToBeTest
            k = int
            # 斷言測試物件o不是k的型別
            self.assertNotIsInstance(o, k, "%s 的型別是%s" % (o, k))
        except AssertionError as e:
            print(e)

    # assertRaises()方法例項
    def test_assertraises(self):
        # 測試丟擲指定的異常型別
        # assertRaises(exception)
        with self.assertRaises(TypeError) as exc:
            random.sample([1, 2, 3, 4, 5, 6], "j")
        # 列印詳細的異常資訊
        print(exc.exception)
        # assertRaises(exception, callable, *args, **kwds)
        try:
            self.assertRaises(ZeroDivisionError, ToBeTest.div, 3, 0)
        except ZeroDivisionError as e:
            print(e)

    # assertRaisesRegexp()方法例項
    def test_assertraisesregex(self):
        # 測試丟擲指定的異常型別，並用正則表示式去匹配異常資訊
        # assertRaisesRegex(exception, regexp)
        with self.assertRaisesRegex(ValueError, "literal") as exc:
            int("abc")
        # 列印詳細的異常資訊
        print(exc.exception)

        # assertRaisesRegex(exception, regexp, callable, *args, **kwds)
        try:
            self.assertRaisesRegex(ValueError, 'invalid literal for.*\'abc\'$', int, 'abc')
        except AssertionError as e:
            print(e)


if __name__ == '__main__':
    unittest.main()