A few days ago, David Heinemeier Hansson
announced
that Turbo 8
is dropping TypeScript
. I'm okay with that because I don't even know what Turbo 8 is. However, over the past few years, some frontend programmers have tried to sell me the idea that "TypeScript is useless, just use tests". I think people with such opinions either don't care about code quality or simply don't know what TypeScript is. Here, I will explain why you should use TypeScript.
Tests are supposed to ensure functionality, not implementation. No useful unit test has ever been made obsolete by a type system. Likewise, if your tests claim your program fulfills its functionality, the type system ads no additional information to the discussion.
My point was that without a type system you need an impossible 100% code coverage, to be sure that you didn’t accidentally mess up some variable assignment or parameter somewhere, since you have nothings to easily and automatically catch those errors.
I understand your point, I just choose to reject it for the reasons given.
I think we are actually saying the same thing though…? Tests should really only ensure functionality. It should be the language’s job to help you with obvious implementation errors (such as using a wrong value type).