Unittest - Test for dict equality

Question

I am trying to do a unit-test but don't quite get why these 2 dicts show up as not equal. I was wondering if someone could give me an explanation for this occurrence. My code is...

import unittest

class TestEmailValidator(unittest.TestCase):

    def test(self):
        known_dict = {
            'debo@foobar.com': True,
            'debo@gmail.com': False
        }

        result_dict = {}

        for key in known_dict.keys():
            result_dict[key] = is_email_valid(key)

        # debugger results
        # result_dict = {
        #    'debo@foobar.com': True,
        #    'debo@gmail.com': False
        # }

        if self.assertEqual(known_dict, result_dict):
            print "is_email_valid passed"
        else:
            print "is_email_valid failed"

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

I get the same result for assertEqual , assertEquals and assertDictEquals . I have tried assigning result_dict to known_dict before the test, but that did not pass either.

It would be great if someone could point me to why this could be happening.

Answer 1

You are misusing the assert. All the assertXYZ methods don't return a boolean value, they just raise an exception if the assertion fails. As these methods don't return anything, they implicitly return None . When evaluating None as a boolean it's treated as false, and hence your test prints is_email_valid failed , even though the test actually passes.