Unexpected declaration error when using symbols and intersections

🔎 Search Terms

• declarations

🕗 Version & Regression Information

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

⏯ Playground Link

https://www.typescriptlang.org/dev/bug-workbench/?#code/PTAEAEDMEsBsFMB2BDAtvAXKWB7A5nvAE4B0ALgM4BQ8AHgA45FmgDGOiFLAMvoUQFUASgElQAXlABlAJ6oARjlgAKAES8CxVQEoA3FRoMmLMjPrxQG-lOIA3aKwuSA3qEg4cWLkWiI8oAF9QADJQZypQUABtK2JhEQBdLFd5ZCIvMh8-QP0A-SoQCBgEFHQsZHpocmpoVEZmUAAqUGQKSz5iNyIcVFBVEmBcTSJVfLp6lgATeFZYNIt2ThZIRAB1LAAeAEEAGlAAIQA+ZWQsLe0JQ9BleSx9i-ErrZCD-XHjUGnZ+bYOLjdEJstsdTqBzpdrrcwQ8nvkvnMiAs-ixaFhYqR0TYiPZHPlCoAZckAfBuAel2CmAAKJGZjwSagWxpaDIeQIUAAcmQrNAAAtWqAmKBoG0AK4UXz+UoWVno+KcyDdXp0MjEFCwUCoHCTIUs1TFTAgQYdEageRClisZCIRA4FjyCwSyYkZQAFgADAAmADM2kME1+SxaEgBq2UtD0ZNAgFByH0fRb-eSBlYhsNAA

💻 Code

// @filename: logger.ts
export const LoggerURI = Symbol("Logger");

export type LoggerService = { foo: string } & {
  [LoggerURI]: { bar: string };
};

// @filename: api.ts
import * as Logger from "./logger";

export declare const fnW: <A, B>(a: A) => (b: B) => A & B;
export declare const fn: <A>(a: A) => (b: A) => A;

declare const x: Logger.LoggerService;

// ❌🤯
// Exported variable 'a' has or is using name 'LoggerURI' from external module "file:///logger" but cannot be named.(4023)
export const a = fnW(x);
// ✅
export const b = fn(x);

🙁 Actual behavior

Unexpected type error:

Exported variable 'a' has or is using name 'LoggerURI' from external module "file:///logger" but cannot be named.(4023)

🙂 Expected behavior

No type error. LoggerURI is exported so it can be named.

Additional information about the issue

No response

Start with the Playground link and the logger.ts and api.ts reproduction, comparing the exported results of fnW(x) and fn(x). Verify declaration generation and the reported 4023 diagnostic; done means the fnW case produces no unexpected error while retaining usable exported declarations.