     var shouldDisconnectImmediately: Bool!
     var receivedPongTimestamps = [Date]()
     static let expectationTimeout = 5.0
-    static let repeatedPingInterval = 1.0
 
     override func setUp() {
         super.setUp()

            return
        }

        if receivedPongTimestamps.count == 5 {
            let timestampOffsets = zip(receivedPongTimestamps.dropFirst(), receivedPongTimestamps).map { $0.timeIntervalSince($1) }
            for offset in timestampOffsets {
                XCTAssertEqual(offset, Self.repeatedPingInterval, accuracy: 0.1)
            }
            pingsWithIntervalExpectation?.fulfill()
        }
        receivedPongTimestamps.append(Date())

    func testPingsWithInterval() {
        pingsWithIntervalExpectation = XCTestExpectation(description: "pingsWithIntervalExpectation")
        socket.connect()
        socket.ping(interval: 0.5)
        wait(for: [pingsWithIntervalExpectation!], timeout: Self.expectationTimeout)
    }

    func testReceiveError() {
