=== tests/cases/compiler/flatArrayNoExcessiveStackDepth.ts ===
// Repro from #43493

declare const foo: unknown[];
>foo : unknown[]

const bar = foo.flatMap(bar => bar as Foo);
>bar : string[]
>foo.flatMap(bar => bar as Foo) : string[]
>foo.flatMap : <U, This = undefined>(callback: (this: This, value: unknown, index: number, array: unknown[]) => U | readonly U[], thisArg?: This | undefined) => U[]
>foo : unknown[]
>flatMap : <U, This = undefined>(callback: (this: This, value: unknown, index: number, array: unknown[]) => U | readonly U[], thisArg?: This | undefined) => U[]
>bar => bar as Foo : (this: undefined, bar: unknown) => Foo
>bar : unknown
>bar as Foo : Foo
>bar : unknown

interface Foo extends Array<string> {}

// Repros from comments in #43249

const repro_43249 = (value: unknown) => {
>repro_43249 : (value: unknown) => void
>(value: unknown) => {    if (typeof value !== "string") {        throw new Error("No");    }    const match = value.match(/anything/) || [];    const [, extracted] = match;} : (value: unknown) => void
>value : unknown

    if (typeof value !== "string") {
>typeof value !== "string" : boolean
>typeof value : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
>value : unknown
>"string" : "string"

        throw new Error("No");
>new Error("No") : Error
>Error : ErrorConstructor
>"No" : "No"
    }
    const match = value.match(/anything/) || [];
>match : RegExpMatchArray
>value.match(/anything/) || [] : RegExpMatchArray
>value.match(/anything/) : RegExpMatchArray | null
>value.match : { (regexp: string | RegExp): RegExpMatchArray | null; (matcher: { [Symbol.match](string: string): RegExpMatchArray | null; }): RegExpMatchArray | null; }
>value : string
>match : { (regexp: string | RegExp): RegExpMatchArray | null; (matcher: { [Symbol.match](string: string): RegExpMatchArray | null; }): RegExpMatchArray | null; }
>/anything/ : RegExp
>[] : never[]

    const [, extracted] = match;
> : undefined
>extracted : string
>match : RegExpMatchArray

};

function f<Arr, D extends number>(x: FlatArray<Arr, any>, y: FlatArray<Arr, D>) {
>f : <Arr, D extends number>(x: FlatArray<Arr, any>, y: FlatArray<Arr, D>) => void
>x : FlatArray<Arr, any>
>y : FlatArray<Arr, D>

    x = y;
>x = y : FlatArray<Arr, D>
>x : FlatArray<Arr, any>
>y : FlatArray<Arr, D>

    y = x;  // Error
>y = x : Arr extends readonly (infer InnerArr)[] ? FlatArray<InnerArr, 0 | 2 | 1 | -1 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20> : Arr
>y : FlatArray<Arr, D>
>x : Arr extends readonly (infer InnerArr)[] ? FlatArray<InnerArr, 0 | 2 | 1 | -1 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20> : Arr
}