export declare function findNpmRoot(extDir: string): string | undefined;
export type NpmRunner = (args: string[], cwd: string) => Promise<{
    code: number;
    stdout: string;
    stderr: string;
}>;
export type NodeRunner = (args: string[]) => Promise<{
    code: number;
    stdout: string;
    stderr: string;
}>;
export declare function setRunNpmForTest(impl: NpmRunner | undefined): void;
export declare function setRunNodeForTest(impl: NodeRunner | undefined): void;
export type InstallOutcome = "ok" | "failed" | "rolled-back";
/**
 * npmDirOverride exists only for tests: the test process is not installed
 * under a node_modules tree, so the real discovery walk can never reach a
 * fixture. Production callers pass nothing and discovery runs as usual.
 */
export declare function autoInstallLatest(latest: string, npmDirOverride?: string): Promise<InstallOutcome>;
export declare function checkForUpdate(autoUpdate: boolean, notify?: (msg: string) => void): Promise<void>;