Find all refs/rename for mapped type symbols

[mhegazy]

type T = { a: number, b: string };
type O = Partial<T>;
var t: T = { a: 1, b: "s" };
var o: O = { a: 3 };

renaming a should rename both instances of a T.a and O.a.

[pavel-agarkov]

Hello.
Rename does not work when you map namespaces or objects imported from another module .
For example:

namespace Core {
    export class Class1 { static order: "1" }
    export class Class2 { static order: "2" }
}

type CoreTypes = keyof typeof Core;
type CoreObject = {[P in CoreTypes]: typeof Core[P]["order"]};
const core: CoreObject = {
    Class1: "1",
    Class2: "2"
}

I don't even talk about order property. The main problem is that class name rename does not rename property of CoreObject.
Everything works the same way when I use imports instead of namespaces:

import * as Core from "./file-with-exported-classes"

IDE: VSCode 1.15.1 / VS2017 15.3.3
TypeScript: 2.5.2
Node: 6.11.0

Would it be considered as a bug/improvement request?
Thank you.

[ghost]

Hi @pavel-agarkov, your example works if you remove the CoreTypes type alias and write type CoreObject = {[P in keyof typeof Core]: typeof Core[P]["order"]}; directly.
A simpler example:

interface X { x: number };
type Key = keyof X;
const a: { [P in Key]: string } = { x: "" }; // Can't find reference for `x`
const b: { [P in keyof X]: string } = { x: "" }; // Successfully find reference for `x`

I'm not sure if this is a bug or a limitation of the way we do mapped types. CC @sandersn

[pavel-agarkov]

Thank you, @Andy-MS
It works as you said.
It a little bit less handy since even my example is way more simplified compared to the real world...
But I can live with it :)

[OliverJAsh]

For some reason this doesn't work when the Record type alias is used:

{
  type T = { a: number, b: string };
  type O = Record<keyof T, {}>;
  var t: T = { a: 1, b: "s" };
  var o: O = { a: 3 };
}

I filed a separate issue #20272