export declare class CredentialStoreUnavailableError extends Error {
    constructor(message?: string);
}
export interface TargetCredentialStore {
    get(service: string, account: string): Promise<string | null>;
    set(service: string, account: string, token: string): Promise<void>;
    delete(service: string, account: string): Promise<void>;
}
export declare function targetServiceKey(targetId: string): string;
export declare const TARGET_ACCOUNT = "refresh-token";
export declare class KeyringCredentialStore implements TargetCredentialStore {
    private readonly Entry;
    private constructor();
    static create(): Promise<KeyringCredentialStore>;
    get(service: string, account: string): Promise<string | null>;
    set(service: string, account: string, token: string): Promise<void>;
    delete(service: string, account: string): Promise<void>;
}
export declare class FakeCredentialStore implements TargetCredentialStore {
    private readonly store;
    private key;
    get(service: string, account: string): Promise<string | null>;
    set(service: string, account: string, token: string): Promise<void>;
    delete(service: string, account: string): Promise<void>;
    has(service: string, account: string): boolean;
    clear(): void;
}