* can return other values to test HTTP edge cases, such as unhappy socket policies or throttled
   * request bodies.
   */
  open fun peek(): MockResponse {
    return MockResponse(socketPolicy = KeepOpen)
  }

  /**
   * Release any resources held by this dispatcher. Any requests that are currently being dispatched

   * callback has returned. Synchronous calls become idle once [execute()][Call.execute] returns.
   * This means that if you are doing synchronous calls the network layer will not truly be idle
   * until every returned [Response] has been closed.
   */
  var idleCallback: Runnable? = null
    get() = this.withLock { field }
    set(value) {
      this.withLock { field = value }
    }