Fix #667 Make no ack an enum case

SocketIO-MacTests/SocketAckManagerTest.swift

@@ -13,14 +13,39 @@ class SocketAckManagerTest: XCTestCase {
     var ackManager = SocketAckManager()
 
     func testAddAcks() {
-        let callbackExpection = self.expectation(description: "callbackExpection")
+        let callbackExpection = expectation(description: "callbackExpection")
         let itemsArray = ["Hi", "ho"]
+
         func callback(_ items: [Any]) {
             callbackExpection.fulfill()
         }
+
         ackManager.addAck(1, callback: callback)
         ackManager.executeAck(1, with: itemsArray, onQueue: DispatchQueue.main)
 
         waitForExpectations(timeout: 3.0, handler: nil)
     }
+
+    func testManagerTimeoutAck() {
+        let callbackExpection = expectation(description: "Manager should timeout ack with noAck status")
+        let itemsArray = ["Hi", "ho"]
+
+        func callback(_ items: [Any]) {
+            XCTAssertEqual(items.count, 1, "Timed out ack should have one value")
+            guard let timeoutReason = items[0] as? String else {
+                XCTFail("Timeout reason should be a string")
+
+                return
+            }
+
+            XCTAssertEqual(timeoutReason, SocketAckStatus.noAck.rawValue)
+
+            callbackExpection.fulfill()
+        }
+
+        ackManager.addAck(1, callback: callback)
+        ackManager.timeoutAck(1, onQueue: DispatchQueue.main)
+
+        waitForExpectations(timeout: 0.2, handler: nil)
+    }
 }

Source/SocketAckManager.swift

@@ -22,8 +22,13 @@
 //  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 //  THE SOFTWARE.
 
+import Dispatch
 import Foundation
 
+public enum SocketAckStatus : String {
+    case noAck = "NO ACK"
+}
+
 private struct SocketAck : Hashable {
     let ack: Int
     var callback: AckCallback!
@@ -73,7 +78,7 @@ struct SocketAckManager {
         let ack = acks.remove(SocketAck(ack: ack))
 
         onQueue.async() {
-            ack?.callback?(["NO ACK"])
+            ack?.callback?([SocketAckStatus.noAck.rawValue])
         }
     }
 }