[zeotroph]

Python is the language with one of the highest 100%-coverage-to-effort ratios. The included unittest.mock framework is making it quite easy to trigger obscure errors and ensure they are handled properly.

Combined with thoughtful use of `# pragma: no cover` a 98% code coverage nowadays is an immediate warning that something was rushed. With this and type checking I feel RuntimeErrors much easier to avoid these days.

And typing, not even a mention?! :) But otherwise a great article, thank you!

[int_19h]

The problem with using mocks extensively for testing is that you then end up mostly testing the mocks. You'll know you've hit that point when you have 100% coverage, but things still break routinely due to interaction (sometimes very indirect) between components.

[HelloNurse]

From the point of view of a programmer setting up a new project, type checking tools are yet another optional linting operation that can be integrated in pre-commit hooks or other automation.