Hacker News new | ask | show | jobs
by zulgan 2169 days ago
this is our take on it: https://eng.rekki.com/unit-testing-at-rekki/t.txt

TLDR:

    * test your core, make sure your core is strong
    * don't test your http api
    * don't mock
    * don't test writing and reading from the database
    * don't complicate your code to make it testable
    * ... unless you deem fit
3 comments
kentosi 2169 days ago
"don't mock"

How are you meant to write a unit test for a class without mocking out external dependencies? Wouldn't that make it an integration test?

link
bencoder 2168 days ago
Not the OP but I count integration testing as testing integrations /between/ systems - wherever your code depends on something outside your codebase. You can mock this for unit testing.

Don't mock things that are already in your codebase. Use the actual object.

Common argument against this I've heard is "But then when something goes wrong it is harder to figure out where the problem is" - I have never actually experienced this myself, but I have, very often, experienced being reluctant to do any refactoring because I'd have to rip up all the unit tests because they are testing only implementation details

link
APhoenixRises 2169 days ago
You definitely have some strong opinions about testing. I'd suggest being more specific so your guidance is more clear. "people who test what they think is appropriate" is really subjective and makes it seem like there's two camps: people who "get" the author's perspective, and those who don't. I've tried the "do" and "don't do" approach, but that's not enough information usually. Teach by examples. Lots of examples. Calling things BS isn't going to change someone's mind. I'd also re-enforce that these practices are for your codebase. Every project is different and has different challenges. There's a reasonable counter-example for each item in your TLDR, and "unless you deem fit" doesn't feel like it gives developers leeway given how strongly you state your opinions.
link
mav3rick 2169 days ago
If you don't do 2 you may as well not test at all. You may do everything else and still fail your end APIs. Your users don't care about your core or mocks. They want end APIs to work

The rest just seem arbitrary. Can you make a change and be confident it works ? The last point sums up everything. "Use your best judgement"

link