enum member key should reject bigint

[JLHwung]

🔎 Search Terms

enum, bigint, member key

🕗 Version & Regression Information

This is the behavior in every version I tried.

⏯ Playground Link

https://www.typescriptlang.org/play/?#code/KYOwrgtgBAolDeAoKKoAYRQLzsQXyA

💻 Code

enum E {
    0n = 0
}

🙁 Actual behavior

Transformed to

"use strict";
var E;
(function (E) {
    E[E[0n] = 0] = 0n;
})(E || (E = {}));

without error

🙂 Expected behavior

It should throw an error "An enum member cannot have a numeric name.", similar to how we handle enum E { 0 = 0 }. Disallowing numeric value 0 but allowing bigInt value 0n as enum member key seems inconsistent.

Additional information about the issue

First reported in babel/babel#17331.