Symbols in `as const` objects should be unique symbols

Bug Report

🔎 Search Terms

symbol object "as const"

🕗 Version & Regression Information

• This is the behavior in every version I tried, and I reviewed the FAQ for entries about symbol

⏯ Playground Link

Playground link with relevant code

💻 Code

const A = Symbol();
const B = Symbol();
const MyEnumA = { A, B } as const;
//    ^?
type MyEnumA = typeof MyEnumA[keyof typeof MyEnumA];
//    ^?
// good

function testA(val: MyEnumA) {}
testA(MyEnumA.A);
testA(MyEnumA.B);
testA(Symbol()); // good type error

const MyEnumB = { C: Symbol(), D: Symbol() } as const;
//    ^?
// should not use generic "symbol" type
type MyEnumB = typeof MyEnumB[keyof typeof MyEnumB];
//    ^?
// should not be symbol

function testB(val: MyEnumB) {}
testB(MyEnumB.C);
testB(MyEnumB.D);
testB(Symbol()); // should be a type error

🙁 Actual behavior

Symbols in as const-ed objects should be unique symbols, instead they're of type symbol.

🙂 Expected behavior

When I write

const obj = { a: Symbol() } as const;

I want obj.a to be a unique symbol.

What I'm trying to do is replace TS enums with symbol-based object "enums" in some scenarios, as it gives me greater typecheck-time and runtime guarantees.

I can do

const A = Symbol();
const MyEnum = { A } as const;
type MyEnum = typeof MyEnum[keyof typeof MyEnum];

and that works great, but I end up with many const ... = Symbol() which pollute the scope and can be misused, when I'd rather do

const MyEnum = { A: Symbol() } as const;
type MyEnum = typeof MyEnum[keyof typeof MyEnum];

Beginne mit der verknüpften TypeScript Playground-Reproduktion und untersuche, wie der Checker Typen für Symbol()-Ausdrücke innerhalb von as const-Objektliteralen ableitet. Als abgeschlossen gilt die Aufgabe, wenn der Inline-Typ MyEnumB unterschiedliche unique symbol-Member verwendet und ein neues Symbol() in den gezeigten Testfällen ablehnt.