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by tinco 1569 days ago
If you're finding bugs in production that a compiler or typechecker could have found then there's something seriously wrong with your test suite. That's how Rails works, if you don't have 90%+ statement coverage it will be hell.
3 comments
eropple 1569 days ago
IME, adding that 90% statement coverage is much of the tedium and frustration of the job in Ruby-land--in particular for things that you just get solved for free with something like TypeScript.

It might have improved somewhat, but I find myself pretty comfortable with a much more pared-down test suite that focuses on correctness tests at logical module boundaries in TypeScript, rather than verifying things the computer can just do. I do look forward to seeing Ruby's gradual typing become more entrenched in the ecosystem, though, because I like the language--I just don't like using the language professionally because of the additional manual work I find myself doing.

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dwaite 1569 days ago
> IME, adding that 90% statement coverage is much of the tedium and frustration of the job in Ruby-land--in particular for things that you just get solved for free with something like TypeScript.

I would argue that if your unit test is only testing things which would have been shown by the type system of another language, you are testing at too low of a level. In addition to being tedious, such tests are often very brittle.

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eropple 1569 days ago
Those tests are brittle, and they're also the thing that protects you at module boundaries when those boundaries are being hammered on by different groups of people.

Having them not be necessary is nice.

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DerArzt 1569 days ago
On the other hand, if you have a compiler/typechecker that finds things that your test suite could find I will always reach for the compiler/typechecker. No sense in writting tests against something a standard tool will find aside from sanitizing data from your inputs.
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aczerepinski 1569 days ago
My experience with ruby is often documenting the expected argument and return types with comments and then writing code and/or tests to enforce the types.

Having also used Go a fair amount, I very much prefer the real type system which both documents and enforces.

I enjoy both languages though.

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