Tests refactoring checklist

Initially, I created a project, but then I realised that it’s not commentable so maybe an umbrella issue with checklist would be more useful, so I duplicate it as such.

@joshwcomeau has mentioned that he would like to have some improvements. So I decided to make some kind of checklist for what has to be done. Feel free to add anything that you think would be nice to do.

Definitely needed:

• Isolate the tests from each other, i.e. make all the setup before each test so that the state is reset #166
• Add tests for appear / enter / leave animations
• Do something with tests stability (see false positives like that: https://travis-ci.org/joshwcomeau/react-flip-move/jobs/236306660) #175
• Add tests for runtime props conversion and checks #174
• Use sandboxed sinon for easier resetting/restoring

Maybe needed:

• Add simple unit tests for helpers — not really needed, they are fully covered by other tests
• Use some code coverage tool like istanbul #172
• Use enzyme for easier react output manipulation #169
• Use sinon fake timers instead of setTimeout

[tobilen]

• regarding " Use sandboxed sinon for easier resetting/restoring", have you given jests mock functionality a look? we’ve replaced also most all of our sandboxes with the mocking toolset provided by jest.

• regarding “Add tests for appear / enter / leave animations” we could look for classes mapped to animation (“–anim-start” etc.) maybe? i mean, short of that you need something like cypress.io for actual e2e testing i wager.

• adding tests for high pressure situations (500 incoming elements, 200 leaving, 600incoming all incoming in short distance). it’ll most likely mess up sorting. we’d then have a red to work up from. i’ll probably build something in that regard this weekend

[joshwcomeau]

Maybe the problem is that we don’t take two skipped frames into account?

Yeah, maybe if CI only runs at 1-2fps, it could explain it.