Add missing `toString` declarations for base types that have them

Search Terms

toString, RegExp, Regular Expression, Boolean, Error

Suggestion

In @typescript-eslint, we have a rule no-base-to-string. This rule ensures that any value that's being coerced to a string has a toString method defined on it.
This is to help catch cases where you accidentally coerce something to a string, and end up with an [object Object] in your strings.

This rule has a pretty simple implementation - it just gets the declarations of the toString method on the type, and ensures that none of the declarations belong to the Object type.
The logic relies upon the fact that every type that actually has a toString method explicitly declares a toString method.

A few of our users ran into cases that were reporting errors for them, even though they shouldn't (https://github.com/typescript-eslint/typescript-eslint/issues/1655).
There's one that specifically has caused people some issues: Boolean/boolean.

I eyeballed the docs and the types, and I am pretty certain there are only 3 types that are missing a toString declaration:

• RegExp: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp/toString
• Boolean: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Boolean/toString
• Error: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error/toString

Related

PR: #37839

Checklist

My suggestion meets these guidelines:

• This wouldn't be a breaking change in existing TypeScript/JavaScript code
• This wouldn't change the runtime behavior of existing JavaScript code
• This could be implemented without emitting different JS based on the types of the expressions
• This isn't a runtime feature (e.g. library functionality, non-ECMAScript syntax with JavaScript output, etc.)
• This feature would agree with the rest of TypeScript's Design Goals.

Bắt đầu bằng cách xác định các khai báo của thư viện chuẩn cho RegExp, Boolean và Error, rồi so sánh các thành viên hiện có của chúng với các JavaScript built-in tương ứng. Xác nhận rằng mỗi khai báo toString còn thiếu đều được biểu diễn trong các kiểu và kiểm tra thay đổi bằng bộ kiểm thử TypeScript liên quan; được xem là hoàn tất khi cả ba kiểu đều khai báo phương thức một cách tường minh mà không thay đổi JavaScript được phát ra.