Add method overloading based on arity

[rmuir]

Currently painless only keys methods, constructors, static methods based on name. This means we cannot have multiple signatures with the same name, which makes it difficult to expand the whitelist.

For example new Date() vs new Date(long).

Here we just allow to overload based on number of parameters vs signatures: to keep everything still simple (including the user since much typing is dynamic and implicit conversions could get complex), but allow improvements for many cases where this is really needed.

For methods i added variants of String.indexOf, but in order to test the ctor and static method case I added a FeatureTest to the whitelist. This also contains getter/setters for loads and stores which we need to test but aren't yet exposed to the whitelist. It needs to be possible to divorce these two things, so we don't have to rush the api just to test.

We key methods on MethodKey (name + arity), but this only impacts the slow path for method lookups, the caching still works the same, so it does not have a performance impact.

[jdconrad]

LGTM! Thanks @rmuir

[uschindler]

LGTM.

About MethodKey: Maybe don't use the MethodKey class at all and instead do it like forbidden: Forbidden creates a pure String key (e.g. 'name@arity').

Thats just an idea.

[rmuir]

I don't think we should mix string concatenation here at all? I also don't plan to use tuple here, ever. that is horrible.

[uschindler]

Sorry the Tuple was a suggestion. I will remove the comment, just for you!

[rmuir]

I would rather painless not have this feature than use that horrible Tuple.

I am afraid if i commit this, that someone will refactor it to use Tuple later.

Quality not quantity.

[uschindler]

I won't do that, trust me. My initial suggestion was to just use simple strings as key, but this involves more overhead in the fallback case (you need to first concat a string + the integer, vs just creating an object for the lookup in the map). So nuke this suggestion, too. For forbiddenapis its fine, but here the solution you brought is better.

[uschindler]

Thanks Robert for commiting! 💯