Add test to check task failure upon user change.

Author: wu-hui

firebase-firestore/src/androidTest/java/com/google/firebase/firestore/FirestoreTest.java

@@ -17,6 +17,7 @@
 import static com.google.firebase.firestore.AccessHelper.getAsyncQueue;
 import static com.google.firebase.firestore.testutil.IntegrationTestUtil.newTestSettings;
 import static com.google.firebase.firestore.testutil.IntegrationTestUtil.provider;
+import static com.google.firebase.firestore.testutil.IntegrationTestUtil.testChangeUserTo;
 import static com.google.firebase.firestore.testutil.IntegrationTestUtil.testCollection;
 import static com.google.firebase.firestore.testutil.IntegrationTestUtil.testCollectionWithDocs;
 import static com.google.firebase.firestore.testutil.IntegrationTestUtil.testDocument;
@@ -44,6 +45,7 @@
 import com.google.firebase.Timestamp;
 import com.google.firebase.firestore.FirebaseFirestoreException.Code;
 import com.google.firebase.firestore.Query.Direction;
+import com.google.firebase.firestore.auth.User;
 import com.google.firebase.firestore.testutil.EventAccumulator;
 import com.google.firebase.firestore.testutil.IntegrationTestUtil;
 import com.google.firebase.firestore.util.AsyncQueue.TimerId;
@@ -1098,23 +1100,47 @@ public void testShutdownCalledMultipleTimes() {
   }
 
   @Test
-  public void testAwaitPendingWritesResolves() {
+  public void testWaitForPendingWritesResolves() {
     DocumentReference documentReference = testCollection("abc").document("123");
     FirebaseFirestore firestore = documentReference.getFirestore();
     Map<String, Object> data = map("foo", "bar");
 
     waitFor(firestore.disableNetwork());
-    Task<Void> awaitsPendingWrites1 = firestore.awaitPendingWrites();
+    Task<Void> awaitsPendingWrites1 = firestore.waitForPendingWrites();
     Task<Void> pendingWrite = documentReference.set(data);
-    Task<Void> awaitsPendingWrites2 = firestore.awaitPendingWrites();
+    Task<Void> awaitsPendingWrites2 = firestore.waitForPendingWrites();
 
-    assertTrue(!awaitsPendingWrites1.isComplete());
+    // `awaitsPendingWrites1` is complete immediately because there is no pending writes at
+    // the time it is created.
+    waitFor(awaitsPendingWrites1);
+    assertTrue(awaitsPendingWrites1.isComplete() && awaitsPendingWrites1.isSuccessful());
     assertTrue(!pendingWrite.isComplete());
     assertTrue(!awaitsPendingWrites2.isComplete());
 
     waitFor(firestore.enableNetwork());
     waitFor(pendingWrite);
-    waitFor(awaitsPendingWrites1);
     waitFor(awaitsPendingWrites2);
+    assertTrue(awaitsPendingWrites2.isComplete() && awaitsPendingWrites2.isSuccessful());
+  }
+
+  @Test
+  public void testWaitForPendingWritesFailsWhenUserChanges() {
+    DocumentReference documentReference = testCollection("abc").document("123");
+    FirebaseFirestore firestore = documentReference.getFirestore();
+    Map<String, Object> data = map("foo", "bar");
+
+    // Prevent pending writes receiving acknowledgement.
+    waitFor(firestore.disableNetwork());
+    Task<Void> pendingWrite = documentReference.set(data);
+    Task<Void> awaitsPendingWrites = firestore.waitForPendingWrites();
+    assertTrue(!pendingWrite.isComplete());
+    assertTrue(!awaitsPendingWrites.isComplete());
+
+    testChangeUserTo(new User("new user"));
+
+    assertTrue(!pendingWrite.isComplete());
+    assertEquals(
+        "'waitForPendingWrites' task is cancelled due to User change.",
+        waitForException(awaitsPendingWrites).getMessage());
   }
 }

firebase-firestore/src/androidTest/java/com/google/firebase/firestore/testutil/IntegrationTestUtil.java

@@ -36,11 +36,13 @@
 import com.google.firebase.firestore.MetadataChanges;
 import com.google.firebase.firestore.QuerySnapshot;
 import com.google.firebase.firestore.auth.EmptyCredentialsProvider;
+import com.google.firebase.firestore.auth.User;
 import com.google.firebase.firestore.core.DatabaseInfo;
 import com.google.firebase.firestore.local.Persistence;
 import com.google.firebase.firestore.model.DatabaseId;
 import com.google.firebase.firestore.testutil.provider.FirestoreProvider;
 import com.google.firebase.firestore.util.AsyncQueue;
+import com.google.firebase.firestore.util.Listener;
 import com.google.firebase.firestore.util.Logger;
 import com.google.firebase.firestore.util.Logger.Level;
 import java.util.ArrayList;
@@ -53,6 +55,34 @@
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.TimeoutException;
 
+class MockCredentialsProvider extends EmptyCredentialsProvider {
+
+  private static MockCredentialsProvider instance;
+
+  public static MockCredentialsProvider instance() {
+    if (MockCredentialsProvider.instance == null) {
+      MockCredentialsProvider.instance = new MockCredentialsProvider();
+    }
+    return MockCredentialsProvider.instance;
+  }
+
+  private MockCredentialsProvider() {
+    super();
+  }
+
+  @Override
+  public void setChangeListener(Listener<User> changeListener) {
+    super.setChangeListener(changeListener);
+    this.listener = changeListener;
+  }
+
+  public void changeUserTo(User user) {
+    listener.onValue(user);
+  }
+
+  private Listener<User> listener;
+}
+
 /** A set of helper methods for tests */
 public class IntegrationTestUtil {
 
@@ -239,7 +269,7 @@ public static FirebaseFirestore testFirestore(
             context,
             databaseId,
             persistenceKey,
-            new EmptyCredentialsProvider(),
+            MockCredentialsProvider.instance(),
             asyncQueue,
             /*firebaseApp=*/ null,
             /*instanceRegistry=*/ (dbId) -> {});
@@ -409,4 +439,8 @@ public static Map<String, Object> toDataMap(QuerySnapshot qrySnap) {
   public static boolean isRunningAgainstEmulator() {
     return CONNECT_TO_EMULATOR;
   }
+
+  public static void testChangeUserTo(User user) {
+    MockCredentialsProvider.instance().changeUserTo(user);
+  }
 }

firebase-firestore/src/main/java/com/google/firebase/firestore/FirebaseFirestore.java

@@ -370,8 +370,8 @@ Task<Void> shutdown() {
    *
    * @return A {@link Task} which resolves when all pending writes are acknowledged by the server.
    */
-  Task<Void> awaitPendingWrites() {
-    return client.awaitPendingWrites();
+  Task<Void> waitForPendingWrites() {
+    return client.waitForPendingWrites();
   }
 
   @VisibleForTesting

firebase-firestore/src/main/java/com/google/firebase/firestore/core/FirestoreClient.java

@@ -228,7 +228,7 @@ public <TResult> Task<TResult> transaction(
    * Returns a task resolves when all the pending writes at the time when this method is called
    * received server acknowledgement. An acknowledgement can be either acceptance or rejections.
    */
-  public Task<Void> awaitPendingWrites() {
+  public Task<Void> waitForPendingWrites() {
     this.verifyNotShutdown();
     if (!remoteStore.canUseNetwork()) {
       Logger.warn(

firebase-firestore/src/main/java/com/google/firebase/firestore/core/SyncEngine.java

@@ -450,6 +450,7 @@ public void registerPendingWritesTask(TaskCompletionSource<Void> userTask) {
     if (largestPendingBatchId == 0) {
       // Complete the task right away if there is no pending writes at the moment.
       userTask.setResult(null);
+      return;
     }
 
     if (pendingWritesCallbacks.containsKey(largestPendingBatchId)) {
@@ -470,6 +471,20 @@ private void resolveTasksAwaitingForPendingWritesIfAny(int batchId) {
     }
   }
 
+  private void failOutstandingPendingWritesAwaitingTasks() {
+    for (Map.Entry<Integer, List<TaskCompletionSource<Void>>> entry :
+        pendingWritesCallbacks.entrySet()) {
+      for (TaskCompletionSource<Void> task : entry.getValue()) {
+        task.setException(
+            new FirebaseFirestoreException(
+                "'waitForPendingWrites' task is cancelled due to User change.",
+                FirebaseFirestoreException.Code.CANCELLED));
+      }
+    }
+
+    pendingWritesCallbacks.clear();
+  }
+
   /** Resolves the task corresponding to this write result. */
   private void notifyUser(int batchId, @Nullable Status status) {
     Map<Integer, TaskCompletionSource<Void>> userTasks = mutationUserCallbacks.get(currentUser);
@@ -605,6 +620,7 @@ public void handleCredentialChange(User user) {
       // Notify local store and emit any resulting events from swapping out the mutation queue.
       ImmutableSortedMap<DocumentKey, MaybeDocument> changes = localStore.handleUserChange(user);
       emitNewSnapsAndNotifyLocalStore(changes, /*remoteEvent=*/ null);
+      failOutstandingPendingWritesAwaitingTasks();
     }
 
     // Notify remote store so it can restart its streams.