Use 'assertIs' to check literal booleans in Python unittest

I used to use Unittest's self.assertTrue / self.assertFalse to check both literal booleans and truthy/falsy values in Unittest. Committed the same sin while writing tests in Django.

I feel like assertTrue and assertFalse are misnomers. They don't specifically check literal booleans, only truthy and falsy states respectively.

Consider this example:

In the above snippet, I've used assertTrue and assertFalse to check both literal booleans and truthy/falsy values. However, to test the literal boolean values, assertIs works better and is more explicit. Here's how to do the above test properly:

Notice how I've used self.assertIs in the is_true and is_false methods to explicitly test out the literal boolean values. The is_truthy and is_falsy methods were kept unchanged from the previous snippet.

Further reading

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