Support ES5-style inheritance with Object.create (Salsa)

[PhaserEditor2D]

TypeScript Version: 2.4.1

Salsa engine does not understand ES3 prototype inheritance.

Code

function A() {
    
}

A.prototype.hello = function (){
};

function B() {
    A.call(this);
}

B.prototype = Object.create(A.prototype);
B.prototype.constructor = B;

var b = new B();
b.[request completions]

Expected behavior:

It should show the list of methods inherited from A, like hello().

Actual behavior:

It does not show the methods from A.

[DanielRosenwasser]

ES3
Object.create

Hmmm. 😄

[DanielRosenwasser]

As a matter of fact, we don't support the @class or @extends annotations either.

[PhaserEditor2D]

The support of @class and @extends could be a simpler solution and a workaround instead of "recognize" the Object.create pattern.

[andi23rosca]

Ran into this issue recently. Any updates?

Might try to make a pull request myself if anyone can point me in the right direction in the code.

[sandersn]

There are two pieces to this:

1. Recognising the pattern. You can look at the binder code like bindObjectDefinePropertyAssignment for an example. It's probably similar.
2. Making constructor functions inherit from other constructor functions, or classes. Constructor functions don't create real class types right now, so there's no way to have them inherit from classes. It's possible to make an ad-hoc fix, or wait on something like my change on the constructor-functions-as-classes branch.

Instead implementing @extends support would make (1) easy but (2) would be the same.

[RyanCavanaugh]

This doesn't seem common enough in modern JS to bother adding support for at this point.