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Editing TS1062:

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TS1062

Type is referenced directly or indirectly in the fulfillment callback of its own 'then' method.

When implementing a non-native promise type, if the type references itself in the `then`` method, this error will occur:

declare class BadPromise {
  then(
    onfulfilled: (value: BadPromise) => any,
    onrejected: (error: any) => any,
  ): BadPromise;
}

async function test() {
  await new BadPromise();
}

Fix: Don't use a recursive type.

To fix the error, don't use a recursive type in the definition of the promise.