Suggestion: Replace `any` with generic types to be able to match the actual and expected values

Hey 👋

Thank you for the great library, I have one specific suggestion here regarding TypeScript

When I use assert.equal, I expect the types of actual and expects values to be the same or expects to be narrowed from actual

The explanation in Playground – https://tsplay.dev/NnXBxW

Do you think it makes sense and I can start working on that? I really want that change as I used it in jest but didn’t really like the experience (I needed to specify it myself to make it implicit)

WDYT?

Other solutions:

• earljs – https://tsplay.dev/Wk5aLN
• TODO: add more examples

I see any for a lot of methods:

I want to cover it for at least:

• is
• equal
• type
• instance
• snapshot (to be able to work with string literal types)
• fixture (same as for snapshot)

[ai]

It will be very cool to have the same typing on both side of is(a, b) and equal(a, b)

[lukeed]

Thanks for the progress @Beraliv ~! Turns out, this was all that was needed (similar idea as yours!):

declare function equal<T,U extends T = T>(a: T, b: U): asserts b is U;

Playground