instanceof AbstractClass.constructor should narrow to typeof AbstracClass

[karfau]

Please try to reproduce the issue with typescript@next. It may have already been fixed.

TypeScript Version: 3.3.0-dev.20181208

Search Terms: static instanceof constructor

Code

type Meta = {foo: string};
abstract class Abstract {
  static meta: Meta;
  public abstract toString(): string;
}

const getMeta = (fromModule: any): Meta | undefined => {
  return fromModule instanceof Abstract.constructor
    ? fromModule.meta : undefined;
};

Expected behavior:
Narrow the type of fromModule to typeof Abstract, so that static fields can be accessed.
(In Typescript versions <= 3.1.6 the above code didn't raise an error, my guess is that the type was not narrowed at all)

Actual behavior:
The narrowed type of fromModule is {}:

Error:(10, 18) TS2339: Property 'meta' does not exist on type '{}'.

Playground Link:
https://www.typescriptlang.org/play/index.html#src=%0D%0Atype%20Meta%20%3D%20%7Bfoo%3A%20string%7D%3B%0D%0Aabstract%20class%20Abstract%20%7B%0D%0A%20%20static%20meta%3A%20Meta%3B%0D%0A%20%20public%20abstract%20toString()%3A%20string%3B%0D%0A%7D%0D%0A%0D%0Aconst%20getMeta%20%3D%20(fromModule%3A%20any)%3A%20Meta%20%7C%20undefined%20%3D%3E%20%7B%0D%0A%20%20return%20fromModule%20instanceof%20Abstract.constructor%0D%0A%20%20%20%20%3F%20fromModule.meta%20%3A%20undefined%3B%0D%0A%7D%3B%0D%0A

Related Issues:
I found the following potentially related issues but they didn't seem to be an exact match or to old (because this problem only exists since 3.2.1):
- #27276
- #23274
- #16035

Workaround
Creating a type guard is of course doable for a single abstract class.

const extendsAbstract = (FromModule: unknown): FromModule is typeof Abstract =>
  FromModule && FromModule instanceof Abstract.constructor;

(Or maybe it could even be written in a generic way?)

[weswigham]

Ref #3841, which is related