Two equally defined mapped types are incompatible

[jtheisen]

TypeScript Version: 2.1.5

Code

class A<T> { a: T }
type M<T> = {[P in keyof T]: A<T[P]>}

function foo<T>(m: (t: T) => M<T>, t: T) {
    let x: {[P in keyof T]: A<T[P]> } = m(t);
}

Expected behavior:

Should compile.

Actual behavior:

Fails to compile at the initialization of x with the claim the types were incompatible:

app.ts(200,9): error TS2322: Type 'M<T>' is not assignable to type '{ [P in keyof T]: A<T[P]>; }'.
  Type 'A<T[P]>' is not assignable to type 'A<T[P]>'. Two different types with this name exist, but they are unrelated.

    Type 'T[P]' is not assignable to type 'T[P]'. Two different types with this name exist, but they are unrelated.

(Maybe this is the expected behavior for some reason, but it seems off to me.)

[ahejlsberg]

Duplicated of #12832. Already fixed in #13448.