tests/cases/compiler/arrayFakeFlatNoCrashInferenceDeclarations.ts(13,10): error TS5088: The inferred type of 'foo' references a type with a cyclic structure which cannot be trivially serialized. A type annotation is necessary.


==== tests/cases/compiler/arrayFakeFlatNoCrashInferenceDeclarations.ts (1 errors) ====
    type BadFlatArray<Arr, Depth extends number> = {obj: {
        "done": Arr,
        "recur": Arr extends ReadonlyArray<infer InnerArr>
        ? BadFlatArray<InnerArr, [-1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20][Depth]>
        : Arr
    }[Depth extends -1 ? "done" : "recur"]}["obj"];
    
    declare function flat<A, D extends number = 1>(
        arr: A,
        depth?: D
    ): BadFlatArray<A, D>[]
    
    function foo<T>(arr: T[], depth: number) {
             ~~~
!!! error TS5088: The inferred type of 'foo' references a type with a cyclic structure which cannot be trivially serialized. A type annotation is necessary.
        return flat(arr, depth);
    }