Fixed Unit Tests

- Fixed the Unit Tests for `EventListener`
- Removed useless Unit Tests for `UIEventReceiver` (a new Unit Test approach will be required here)

Author: LK-Simon

Tests/EventDrivenSwiftTests/BasicEventListenerTests.swift

@@ -0,0 +1,55 @@
+//
+//  BasicEventListenerTests.swift
+//  
+//
+//  Created by Simon Stuart on 12/08/2022.
+//
+
+import XCTest
+import ThreadSafeSwift
+@testable import EventDrivenSwift
+
+final class BasicEventListenerTests: XCTestCase {
+    struct TestEventTypeOne: Eventable {
+        var foo: Int
+    }
+    
+    var myFoo = 0
+    var listenerToken: UUID? = nil
+    let testOne = TestEventTypeOne(foo: 1000) // Create the Event
+    var awaiter = DispatchSemaphore(value: 0)
+
+    func testEventListenerOnListenerThread() throws {
+        XCTAssertEqual(myFoo, 0, "Expect initial value of eventThread.foo to be 0, but it's \(myFoo)")
+        
+        listenerToken = TestEventTypeOne.addListener(self, { (event: TestEventTypeOne, priority) in
+            self.myFoo = event.foo
+            self.awaiter.signal()
+        }, executeOn: .listenerThread)
+        
+        testOne.queue()
+        
+        let result = awaiter.wait(timeout: DispatchTime.now().advanced(by: DispatchTimeInterval.seconds(10)))
+        XCTAssertEqual(result, .success, "The Event Handler was not invoked in time!")
+        XCTAssertEqual(self.myFoo, testOne.foo, "Expect new value of eventThread.foo to be \(testOne.foo), but it's \(self.myFoo)")
+        
+        TestEventTypeOne.removeListener(listenerToken!)
+    }
+    
+    func testEventListenerOnTaskThread() throws {
+        XCTAssertEqual(myFoo, 0, "Expect initial value of eventThread.foo to be 0, but it's \(myFoo)")
+        
+        listenerToken = TestEventTypeOne.addListener(self, { (event: TestEventTypeOne, priority) in
+            self.myFoo = event.foo
+            self.awaiter.signal()
+        }, executeOn: .taskThread)
+        
+        testOne.queue()
+        
+        let result = awaiter.wait(timeout: DispatchTime.now().advanced(by: DispatchTimeInterval.seconds(10)))
+        XCTAssertEqual(result, .success, "The Event Handler was not invoked in time!")
+        XCTAssertEqual(self.myFoo, testOne.foo, "Expect new value of eventThread.foo to be \(testOne.foo), but it's \(self.myFoo)")
+        
+        TestEventTypeOne.removeListener(listenerToken!)
+    }
+}