Missing test for TimerManager (#69)

pubnub-chat-impl/src/commonTest/kotlin/com/pubnub/internal/TimerManagerTest.kt

@@ -14,7 +14,7 @@ import kotlin.time.Duration.Companion.seconds
 
 class TimerManagerTest {
     @Test
-    fun cancelOneOff() = runTest {
+    fun destroy_oneOffTask() = runTest {
         val timerManager = createTimerManager()
         val completable1 = CompletableDeferred<Unit>()
         val completable2 = CompletableDeferred<Unit>()
@@ -41,7 +41,7 @@ class TimerManagerTest {
     }
 
     @Test
-    fun cancelPeriodic() = runTest {
+    fun destroy_periodicTask() = runTest {
         val timerManager = createTimerManager()
         val counter = atomic(0)
         val counter2 = atomic(0)
@@ -71,4 +71,43 @@ class TimerManagerTest {
         assertEquals(1, counter.value)
         assertEquals(3, counter2.value)
     }
+
+    @Test
+    fun cancelSingleTasks() = runTest {
+        val timerManager = createTimerManager()
+        val counter = atomic(0)
+        val counter2 = atomic(0)
+        val counter3 = atomic(0)
+
+        // this should run 1 time
+        val timer1 = timerManager.runWithDelay(1.seconds) {
+            counter.incrementAndGet()
+        }
+        // this should run 3 times
+        // let's also try to start it from a background thread to test if cancellation works in that case
+        val timer2 = withContext(Dispatchers.Default) {
+            timerManager.runPeriodically(0.5.seconds) {
+                counter2.incrementAndGet()
+            }
+        }
+        // this should not run
+        val timer3 = timerManager.runWithDelay(2.seconds) {
+            counter3.incrementAndGet()
+        }
+
+        withContext(Dispatchers.Default) {
+            delay(1.75.seconds)
+        }
+        timer1.cancel()
+        timer2.cancel()
+        timer3.cancel()
+
+        withContext(Dispatchers.Default) {
+            delay(1.seconds)
+        }
+
+        assertEquals(1, counter.value)
+        assertEquals(3, counter2.value)
+        assertEquals(0, counter3.value)
+    }
 }