Bug: Fix bad duplicate name resolution

[jasisk]

We were using require.resolve to ensure we used the built-in resolution mechanism however this is insufficient.

require.resolve will resolve if given a path with extension but, without one, it attepts to resolve with the registered extensions. That's why we did it. Problem is, if you have two files with the same name but different extensions, both will pass the resolution test if at least one of them uses a registered extension.

This change supports the existing resolution process in node (treat extension-less files as *.js, check files with extensions against the registered handlers). It will also prevent errors from spawning when a file fails to load (though it will still fail loudly if the loaded file doesn't have a signature of function (thing) {}.

Closes #77

[aredridel]

Will this mess up coffeescript users?

[jasisk]

Will this mess up coffeescript users?

Nope. Checks against registered require extensions just the same (see the custom extension test). I don't like recreating core resolution functionality but c'est la vie.

[aredridel]

Makes sense. LGTM then!

[totherik]

👍

[xjamundx]

I have no rights on this repo, but I have verified the issue and it addresses the problem I reported in #77

[jasisk]

Publishing this as a patch. It may cause some problems but it will be with folks relying on behavior that is counter the documentation.