File: mappedTypeNotMistakenlyHomomorphic.types

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=== tests/cases/compiler/mappedTypeNotMistakenlyHomomorphic.ts ===
enum ABC { A, B }
>ABC : ABC
>A : ABC.A
>B : ABC.B

type Gen<T extends ABC> = { v: T; } & (
>Gen : Gen<T>
>v : T
  {
    v: ABC.A,
>v : ABC.A
>ABC : any

    a: string,
>a : string

  } | {
    v: ABC.B,
>v : ABC.B
>ABC : any

    b: string,
>b : string
  }
)

// Quick info: ???
//
// type Gen2<T extends ABC> = {
//    v: string;
// }
//
type Gen2<T extends ABC> = {
>Gen2 : Gen2<T>

  [Property in keyof Gen<T>]: string;
};

// 'a' and 'b' properties required !?!?
const gen2TypeA: Gen2<ABC.A> = { v:  "I am A", a: "" };
>gen2TypeA : Gen2<ABC.A>
>ABC : any
>{ v:  "I am A", a: "" } : { v: string; a: string; }
>v : string
>"I am A" : "I am A"
>a : string
>"" : ""

const gen2TypeB: Gen2<ABC.B> = { v:  "I am B", b: "" };
>gen2TypeB : Gen2<ABC.B>
>ABC : any
>{ v:  "I am B", b: "" } : { v: string; b: string; }
>v : string
>"I am B" : "I am B"
>b : string
>"" : ""

// 'v' ???
type K = keyof Gen2<ABC.A>;
>K : "v" | "a"
>ABC : any

// :(
declare let a: Gen2<ABC.A>;
>a : Gen2<ABC.A>
>ABC : any

declare let b: Gen2<ABC.B>;
>b : Gen2<ABC.B>
>ABC : any

a = b;
>a = b : Gen2<ABC.B>
>a : Gen2<ABC.A>
>b : Gen2<ABC.B>

b = a;
>b = a : Gen2<ABC.A>
>b : Gen2<ABC.B>
>a : Gen2<ABC.A>