Oh I’m fully aware that python lets you cheat dependency injection with patch, its one of the many things python teaches developers to do wrong, which leads them to be unable to use any other language.
While my experience is mostly C++, I assume these mocking libraries are similar in allowing you to create a class that can report it’s own usage, and allow for arbitrary returns values and side effects, which is incredibly useful, especially in conjunction with dependency injection.
What patch lets you do is directly overwrite the functionality of private member functions on the fly, which if Java/JavaScript can do I’d love to know, I thought this was a uniquely Pythonic magic.
Quickest way to get a test suite so tightly coupled to structure rather than behavior that even just looking at the tests wrong makes them fail. But technically you do get test coverage I guess. Goodhart’s law in action.
with patch("some_file.requests.get", side_effect=SomeException("oh no")): result = func_using_requests()Though not every language makes mocking as easy, and multiple responsibilities in a single function can quickly get messy.
Oh I’m fully aware that python lets you cheat dependency injection with patch, its one of the many things python teaches developers to do wrong, which leads them to be unable to use any other language.
I vaguely remember Java also has mocking libraries, as does JavaScript. (Though JavaScript isn’t a language I’d hold up as the ideal.)
While my experience is mostly C++, I assume these mocking libraries are similar in allowing you to create a class that can report it’s own usage, and allow for arbitrary returns values and side effects, which is incredibly useful, especially in conjunction with dependency injection.
What
patchlets you do is directly overwrite the functionality of private member functions on the fly, which if Java/JavaScript can do I’d love to know, I thought this was a uniquely Pythonic magic.Javascript has mocking with jest: https://jestjs.io/docs/mock-functions
There’s an example there of mocking our axios (a common library for network requests, a la python requests)
It’s been a long time since I’ve used java, but mockito exists: https://site.mockito.org/javadoc/current/org/mockito/Mockito.html#2
(Usage note for anyone unfamiliar, but despite the name java and JavaScript are radically different languages.)
Quickest way to get a test suite so tightly coupled to structure rather than behavior that even just looking at the tests wrong makes them fail. But technically you do get test coverage I guess. Goodhart’s law in action.