fix: flaky tests randomly fail due to enqueuing operation in background

Author: jinliu9508

OneSignalSDK/onesignal/core/src/main/java/com/onesignal/common/threading/OSPrimaryCoroutineScope.kt

@@ -16,4 +16,6 @@ object OSPrimaryCoroutineScope {
             block()
         }
     }
+
+    suspend fun waitForIdle() = mainScope.launch { }.join()
 }

OneSignalSDK/onesignal/core/src/test/java/com/onesignal/core/internal/operations/OperationRepoTests.kt

@@ -1,5 +1,6 @@
 package com.onesignal.core.internal.operations
 
+import com.onesignal.common.threading.OSPrimaryCoroutineScope
 import com.onesignal.common.threading.Waiter
 import com.onesignal.common.threading.WaiterWithValue
 import com.onesignal.core.internal.operations.impl.OperationModelStore
@@ -157,6 +158,7 @@ class OperationRepoTests : FunSpec({
         // When
         operationRepo.start()
         operationRepo.enqueue(MyOperation())
+        OSPrimaryCoroutineScope.waitForIdle()
 
         // Then
         operationRepo.containsInstanceOf<MyOperation>() shouldBe true
@@ -261,6 +263,7 @@ class OperationRepoTests : FunSpec({
         // When
         opRepo.start()
         opRepo.enqueue(mockOperation())
+        OSPrimaryCoroutineScope.waitForIdle()
         val response1 =
             withTimeoutOrNull(999) {
                 opRepo.enqueueAndWait(mockOperation())
@@ -639,6 +642,7 @@ class OperationRepoTests : FunSpec({
         mocks.operationRepo.start()
         mocks.operationRepo.enqueue(operation1)
         mocks.operationRepo.enqueue(operation2)
+        OSPrimaryCoroutineScope.waitForIdle()
         mocks.operationRepo.enqueueAndWait(operation3)
 
         // Then
@@ -719,6 +723,7 @@ class OperationRepoTests : FunSpec({
         val mocks = Mocks()
         val op = mockOperation()
         mocks.operationRepo.enqueue(op)
+        OSPrimaryCoroutineScope.waitForIdle()
 
         // When
         mocks.operationRepo.loadSavedOperations()
@@ -759,6 +764,7 @@ class OperationRepoTests : FunSpec({
         // When
         opRepo.start()
         opRepo.enqueue(mockOperation())
+        OSPrimaryCoroutineScope.waitForIdle()
         val response1 =
             withTimeoutOrNull(999) {
                 opRepo.enqueueAndWait(mockOperation())