Spurious "referenced directly or indirectly in its own initializer" when combined with narrowing, asserts function, and loop

Bug Report

🔎 Search Terms

referenced directly or indirectly asserts

🕗 Version & Regression Information

• This is the behavior in every version I tried

⏯ Playground Link

Playground Link

💻 Code

declare const myRequire: ((p: string) => {} | undefined) | undefined;

declare function assertIsDefined<T>(value: T): asserts value is NonNullable<T>

function fn1() {
    if (!myRequire) {
        return;
    }

    for (const p of ["a", "b"]) {
        // Error?
        const result = myRequire("something");
        assertIsDefined(result);
    }
}

🙁 Actual behavior

result is claimed to be referenced directly or indirectly in its initializer.

Modifying the code in various ways makes the error go away.

🙂 Expected behavior

No error; there's no relationship between the initializer and the result.

Beginne mit dem verlinkten TypeScript Playground und führe das bereitgestellte Codebeispiel aus, um die Diagnose zu reproduzieren. Untersuche, wie der Compiler Narrowing, asserts functions und die Schleife um den Initializer behandelt. Als erledigt gilt die Aufgabe, wenn das Beispiel nicht mehr meldet, dass result in seinem eigenen Initializer referenziert wird, während das erwartete Narrowing-Verhalten intakt bleibt.