The unittest module provides assertion methods specific to common types and operations. Both versions will test the same things, but
the dedicated one will provide a better error message, simplifying the debugging process.
This rule reports an issue when an assertion can be simplified by using a more specific function. The array below gives a list of assertions on
which an issue will be raised, and which function should be used instead:
||Original||Dedicated||
|assertTrue(x == y)|assertEqual(x, y)|
|assertTrue(x != y)|assertNotEqual(x, y)|
|assertFalse(x == y)|assertNotEqual(x, y)|
|assertFalse(x != y)|assertEqual(x, y)|
|assertTrue(x < y)|assertLess(x, y)|
|assertTrue(x <= y)|assertLessEqual(x, y)|
|assertTrue(x > y)|assertGreater(x, y)|
|assertTrue(x >= y)|assertGreaterEqual(x, y)|
|assertTrue(x is y)|assertIs(x, y)|
|assertTrue(x is not y)|assertIsNot(x, y)|
|assertFalse(x is y)|assertIsNot(x, y)|
|assertFalse(x is not y)|assertIs(x, y)|
|assertTrue(x in y)|assertIn(x, y)|
|assertFalse(x in y)|assertNotIn(x, y)|
|assertTrue(isinstance(x, y))|assertIsInstance(x, y)|
|assertFalse(isinstance(x, y))|assertNotIsInstance(x, y)|
|assertEqual(x, round(y, z))|assertAlmostEqual(x, y, z)|
|assertAlmostEqual(x, round(y, z))|assertAlmostEqual(x, y, z)|
|assertNotEqual(x, round(y, z))|assertNotAlmostEqual(x, y, z)|
|assertNotAlmostEqual(x, round(y, z))|assertNotAlmostEqual(x, y, z)|
|assertEqual(x, None)|assertIsNone(x)|
|assertNotEqual(x, None)|assertIsNotNone(x)|
|assertTrue(x is None)|assertIsNone(x)|
|assertTrue(x is not None)|assertIsNotNone(x)|
|assertFalse(x is None)|assertIsNotNone(x)|
|assertFalse(x is not None)|assertIsNone(x)|
|assertEqual(x, True)|assertTrue(x)|
|assertEqual(x, False)|assertFalse(x)|
Noncompliant code example
import unittest
class SomeTest(unittest.TestCase):
def test_something(self):
x = foo()
y = bar()
self.assertFalse(x == y) # Noncompliant
self.assertTrue(x < y) # Noncompliant
Compliant solution
class SomeTest(unittest.TestCase):
def test_something(self):
x = foo()
y = bar()
self.assertNotEqual(x, y)
self.assertLess(x, y)
