     }
 
     var shouldDisconnectImmediately: Bool!
+    var receivedPongTimestamps = [Date]()
     static let expectationTimeout = 5.0
+    static let repeatedPingInterval = 0.5
 
     override func setUp() {
         super.setUp()

            shouldDisconnectImmediately = false
        }
    }
    var pongExpectation: XCTestExpectation! {
        didSet {
            shouldDisconnectImmediately = false
        }


    func webSocketDidConnect(connection: WebSocketConnection) {
        connectExpectation?.fulfill()

        if shouldDisconnectImmediately {
            socket.disconnect()
        }
