Python unittest – assertTrue() function
assertTrue() in Python is a unittest library function that is used in unit testing to compare test value with true. This function will take two parameters as input and return a boolean value depending upon the assert condition. If test value is true then assertTrue() will return true else return false.
Syntax: assertTrue(testValue, message)
Parameters: assertTrue() accepts two parameters which are listed below with explanation:
- testValue: variable of boolean 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.
Listed below are two different examples illustrating the positive and negative test case for given assert function:
Example 1: Negative Test case
Python3
# unit test caseimport unittestclass TestStringMethods(unittest.TestCase): # test function def test_negative(self): testValue = False # error message in case if test case got failed message = "Test value is not true." # assertTrue() to check true of test value self.assertTrue( testValue, message)if __name__ == '__main__': unittest.main() |
Output:
F
======================================================================
FAIL: test_negative (__main__.TestStringMethods)
----------------------------------------------------------------------
Traceback (most recent call last):
File "p1.py", line 11, in test_negative
self.assertTrue( testValue, message)
AssertionError: False is not true : Test value is not true.
----------------------------------------------------------------------
Ran 1 test in 0.000s
FAILED (failures=1)
Example 2: Positive Test case
Python3
# unit test caseimport unittestclass TestStringMethods(unittest.TestCase): # test function def test_positive(self): testValue = True # error message in case if test case got failed message = "Test value is not true." # assertTrue() to check true of test value self.assertTrue( testValue, message)if __name__ == '__main__': unittest.main() |
Output:
. ---------------------------------------------------------------------- Ran 1 test in 0.000s OK
