Python unittest – assertEqual()函数

Python中的 assertEqual() 是一个 unittest 库函数，用于在单元测试中检查两个值的相等性。该函数将三个参数作为输入，并根据断言条件返回一个布尔值。如果两个输入值相等，assertEqual() 将返回 true，否则返回 false。

Syntax: assertEqual(firstValue, secondValue, message)

Parameters: assertEqual() accept three parameter which are listed below with explanation:

• firstValue  variable of any type which is used in the comparison by function
• secondValue: variable of any type which is used in the comparison by function
• message: a string sentence as a message which got displayed when the test case got failed.

下面列出了两个不同的示例，说明了给定断言函数的正负测试用例：

示例 1：否定测试用例

Python3

# unit test case
import unittest
  
class TestStringMethods(unittest.TestCase):
    # test function to test equality of two value
    def test_negative(self):
        firstValue = "geeks"
        secondValue = "gfg"
        # error message in case if test case got failed
        message = "First value and second value are not equal !"
        # assertEqual() to check equality of first & second value
        self.assertEqual(firstValue, secondValue, message)
  
if __name__ == '__main__':
    unittest.main()

输出：

F
======================================================================
FAIL: test_negative (__main__.TestStringMethods)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "p1.py", line 12, in test_negative
    self.assertEqual(firstValue, secondValue, message)
AssertionError: 'geeks' != 'gfg'
- geeks
+ gfg
 : First value and second value are not equal!

----------------------------------------------------------------------
Ran 1 test in 0.000s

FAILED (failures=1)

示例 2：正面测试用例

Python3

# unit test case
import unittest
  
class TestStringMethods(unittest.TestCase):
    # test function to test equality of two value
    def test_positive(self):
        firstValue = "geeks"
        secondValue = "geeks"
        # error message in case if test case got failed
        message = "First value and second value are not equal !"
        # assertEqual() to check equality of first & second value
        self.assertEqual(firstValue, secondValue, message)
  
if __name__ == '__main__':
    unittest.main()

输出：

.
----------------------------------------------------------------------
Ran 1 test in 0.000s

OK

参考：https://docs。 Python.org/3/library/unittest.html