Major Improvements 2

[graphemecluster]

Sorry for another PR! Unlike the previous (closed) one, this PR should be mergeable without any external actions required.

This PR brings type safety to typed array and extends #7 to the find and findIndex methods.

Introduces a single utility type CheckNonNullable, which is unnecessary with the type of o being replaced to {} after TypeScript 4.8 due to microsoft/TypeScript#49119.

The first parameter of {Array, %TypedArray%}.from are all renamed to source because writing iterable: Iterable<T> | ArrayLike<T> is kind of misleading, and it is also named source in the spec text.

This PR does not include tests for methods with only thisArg changes, or it will be superfluous.

I think some bugs like this: void in the original library files should be reported to TypeScript, and I am surprised that the return type of the first parameter of the %TypedArray%.prototype methods in the original es2020.bigint.d.ts file are already typed boolean, in contrast to the Array.prototype methods in es5.d.ts.

[graphemecluster]

I hope the generation code could be rewritten such that the files are transformed and emitted using the API instead of printing the statements one by one by text. This way it will be far easier to maintain the code, and the code can even be written such that we need not to repeat the documentations in the lib files.
However I don’t want to modify the generation logic too much, unless you explicitly allow me to do so (and the main reason is that I haven’t got the time).

[graphemecluster]

Do you wish that I commit the VSCode launch.json for debugging?

[uhyo]

Thank you!

This way it will be far easier to maintain the code, and the code can even be written such that we need not to repeat the documentations in the lib files.

Yes that'd be nice, although I haven't come up with a nice way of achieving this 🤕

Do you wish that I commit the VSCode launch.json for debugging?

Yes that's fine 🙂

[uhyo]

Thank you, sorry for being late 🤕

[graphemecluster]

Don't forget to publish a new release whenever you're free! 😉