Implement type narrowing for Array.prototype.includes

[jrandolf]

⚙ Compilation target

ES2016

⚙ Library

ESNext

Missing / Incorrect Definition

Array.prototype.includes and ReadonlyArray.prototype.includes

Sample Code

const candidates = ["foo", "bar"] as const;
const candidate: string = "baz";
// Argument of type '"string"' is not assignable to parameter of type '"foo" | "bar"'.
candidates.includes(candidate);

See #58988

Documentation Link

No response

[MartinJohns]

Duplicate of #55090 / #14520.

[jrandolf]

Looks like this issue is a sub-issue of #14520 as the parent can fix this one. I'll leave this open though since this specific instance has a potential fix associated with it.

[MartinJohns]

Your potential fix has been rejected before already: #53904 (comment)

The proposed signature allows any argument, which we consider to be too loose