Use AssertIsNotNone when checking against None
assertIsNone and assertIsNotNone provide more helpful failure messages than assertTrue or assertFalse.
When performing checks against None it's better to use the correct tool for the job: assertIsNone and assertIsNotNone are provided explicitly for this task.
The difference is assertion methods such as assertTrue will report the message:
AssertionError: False is not True
While assertIsNone will provided a much more helpful message:
AssertionError: 'foo' is not None
Good quality failure messages allows the failure mode to be understood rapidly and therefore the problem to be fixed more quickly.
If our GitHub code review bot spots this issue in your pull request it gives this advice:
code-review-doctorbot just nowtests.py
1 | + | class TestFeature(unittest.TestCase): | |
2 | + | def test_feature(self): | |
3 | + | self.assertTrue(value is not None) |
assertIsNone and assertIsNotNone provide more helpful failure messages than assertTrue or assertFalse.
Suggested changes
- | self.assertTrue(value is not None) |
+ | self.assertIsNotNone(value) |
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