import { type BigIntStats } from "node:fs";
export declare function need(value: unknown, code: string): asserts value;
export declare function snapshot(file: string, privateFile?: boolean, options?: {
    readOnlyPackage?: true;
}): {
    file: string;
    privateFile: boolean;
    readOnlyPackage: boolean;
    text: string;
    bytes: Buffer<ArrayBuffer>;
    stat: BigIntStats;
    sha256: string;
};
export declare function unchanged(before: ReturnType<typeof snapshot>): void;
export declare function save(file: string, content: string | Buffer): void;