Const enum initializer rejects a const variable initialized from an enum member #3640

const enum Source { A = 4 }
const value = Source.A;
const enum Result { A = value }
console.log(Result.A);

SharpTS at 89311999a rejects this with --no-tsconfig --strict --noEmit: Expression type 'Variable' is not allowed in const enum initializer.

TypeScript 6.0.3 accepts it with --ignoreConfig --strict --target ES2022, and its emitted JavaScript prints 4.

The enum constant recorder handles literal, variable, grouping, unary and binary const initializers, but does not record a constant whose initializer is a qualified enum member. The intervening const variable should retain the enum member's constant value. Found while verifying qualified enum member initializer support for #3630. This is distinct from referring to Source.A directly in the enum initializer.