What's your opinion and/or experience on the subject? 🙂 Why don't you agree? 🤔
I guess, I'm a fan of low-level logic testing. ie. testing the nitty gritty implementation details as well as the high-level logic. But I think that has to do with programming style.
I'm generally a fan of building very small light-weight libraries/bags of functions that build on each other and I generally love testing from the ground up based on that. Eg. functions -> internal library -> business logic -> actual API
For example, at my job, we built our internal API in Elixir and it has a fairly high test coverage but what's interesting is the "levels" of abstractions at which we test:
Generally speaking, the only functions that are ever "private" tend to be wrappers that call another helper/model/query/etc. that already have test coverage.
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