declare namespace MockRaf {
    interface Options {
        /** The time that should pass during each requestAnimationFrame step in milliseconds. Default is roughly equivalent to default browser behavior. */
        time?: number | undefined;

        /** The number of steps to take. */
        count?: number | undefined;
    }

    /** Creates a mockRaf instance, exposing the functions you'll use to interact with the mock. */
    interface Creator {
        /**
         * Returns the current now value of the mock. Starts at 0 and increases with each step() taken.
         * Useful for stubbing out performance.now() or a polyfill when using requestAnimationFrame with timers.
         */
        now(): number;

        /** Replacement for requestAnimationFrame or a polyfill.Adds a callback to be fired on the next step. */
        raf(callback: FrameRequestCallback): number;

        /** Replacement for cancelAnimationFrame or a polyfill.Removes all currently scheduled requestAnimationFrame callbacks from the queue. */
        cancel(handle: number): void;

        /** Takes requestAnimationFrame steps. Fires currently queued callbacks for each step and increments now time for each step. The primary way to interact with a mockRaf instance for testing. */
        step(options?: Options): void;
    }
}

declare function MockRaf(): MockRaf.Creator;

export = MockRaf;