fix(expect, @jest/expect): do not infer argument types of *CalledWith and *ReturnedWith matchers

[mrazauskas]

Fixes #13337

Summary

Unfortunately #13268 and #13278 have to be reverted. As reported, type inference does not work with function overloads. I have to add that it also does not work with asymmetric matchers.

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The asymmetric matchers return AsymmetricMatcher type. To make the inference work with an argument of [a: string] type, it is needed to remap it into [a: string | AsymmetricMatcher]. Could be possible with something like:

type Remapped<T> = T | AsymmetricMatcher

A tuple should be broken into elements and turned into remapped tuple. And this is the hard part:

type InferTest<T extends [...Array<unknown>]> = T extends [infer H] ? H : never;

InferTest<[a: number]>; // this is `number`
InferTest<[b?: number]>; // but this is `never`!!!

The optional args are simply discarded during inference. That is because TypeScript assumes that the optional args are simply not there. It could be there or it could not in a tuple type, but if a type of tuple member is turned into a type of a variable? There isn’t such a thing as an optional variable. That’s why the Remapped type has no chance to work.

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I couldn’t find a solution. Perhaps it makes sense to revert it for now, because types are obviously buggy.

Test plan

Type tests with asymmetric matchers are added for the future. These are failing on main.

[SimenB]

great you've added tests that catch this 👍

[mrazauskas]

I was sure you wouldn’t accept this PR without these tests (;

[SimenB]

😀

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