A neat testing pattern is writing common tests in a base class and then applying them to multiple objects through subclassing. Doing so can help you test smarter and cover more code with less boilerplate.| adamj.eu
In Python, a mixin class is a class that is not intended to be used directly, but instead “mixed in” to other classes through multiple inheritance. Mixins are not really a language feature but more of a conventional pattern allowed by Python’s multiple inheritance rules. Unfortunately, adding type hints to mixin classes can be tricky because they implicitly require subclasses to fit a certain shape.| adamj.eu
When we write custom management commands, it’s easy to write integration tests for them with call_command(). This allows us to invoke the management command as it runs under manage.py, and retrieve the return code, standard output, and standard error. It’s great, but has some overhead, making our tests slower than necessary. If we have logic separated out of the command’s handle() method, it improves both readability and testability, as we can unit test it separately.| adamj.eu
Sometimes, you want to test a function that uses an inner import and mock that imported object. For example, say you wanted to mock dig() in this example:| adamj.eu
