Python - assertLessEqual() function in unittest

assertLessEqual() in Python is an unittest library function that is used in unit testing to check whether the first given value is less than or equal to the second value or not. This function will take three parameters as input and return a boolean value depending upon the assert condition.

This function checks that if the first given value is less than or equal to the second value and returns true if it is so, else return false if the first value is not less than or equal to the second value.

Syntax: assertLessEqual(first, second, message=None)

Parameters: assertLessEqual() accept three parameters which are listed below with explanation:

• first: first input value (integer)
• second:  second input value (integer)
• message: a string sentence as a message which got displayed when the test case got failed.

Listed below is an example illustrating the positive and negative test case for given assert function:

Example 1:

# test suite
import unittest

class TestStringMethods(unittest.TestCase):
  
    # negative test function to test if values1 is less or equal than value2
    def test_negativeForLessEqual(self):
        first = 6
        second = 5
        
        # error message in case if test case got failed
        message = "first value is not less than or equal to second value."
        
        # assert function() to check if values1 is less or equal than value2
        self.assertLessEqual(first, second, message)

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

Output:

F ====================================================================== FAIL: test_negativeForLessEqual (__main__.TestStringMethods) ---------------------------------------------------------------------- Traceback (most recent call last):  File "p1.py", line 13, in test_negativeForLessEqual    self.assertLessEqual(first, second, message) AssertionError: 6 not less than or equal to 5 : first value is not less than or equal to second value. ---------------------------------------------------------------------- Ran 1 test in 0.000s FAILED (failures=1)

Example 2:

# test suite
import unittest

class TestStringMethods(unittest.TestCase):
  
    # positive test function to test if value1 is less or equal than value2
    def test_positiveForLessEqual(self):
        first = 4
        second = 4
        
        # error message in case if  test case got failed
        message = "first value is not less than or equal to second value."
        
        # assert function() to check if values1 is less or equal than value2
        self.assertLessEqual(first, second, message)


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

Output:

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