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Author: wu-hui

firebase-firestore/src/main/java/com/google/firebase/firestore/local/LocalDocumentsView.java

@@ -203,8 +203,7 @@ private void recalculateAndSaveOverlays(Map<DocumentKey, MutableDocument> docs)
     // along the way.
     for (MutationBatch batch : batches) {
       for (DocumentKey key : batch.getKeys()) {
-        FieldMask mask =
-            masks.containsKey(key) ? masks.get(key) : FieldMask.fromSet(new HashSet<>());
+        FieldMask mask = masks.containsKey(key) ? masks.get(key) : FieldMask.EMPTY;
         mask = batch.applyToLocalView(docs.get(key), mask);
         masks.put(key, mask);
         int batchId = batch.getBatchId();

firebase-firestore/src/main/java/com/google/firebase/firestore/model/mutation/FieldMask.java

@@ -15,6 +15,7 @@
 package com.google.firebase.firestore.model.mutation;
 
 import com.google.firebase.firestore.model.FieldPath;
+import java.util.HashSet;
 import java.util.Set;
 
 /**
@@ -26,6 +27,8 @@
  * object foo. If foo is not an object, foo is replaced with an object containing foo.
  */
 public final class FieldMask {
+  public static FieldMask EMPTY = fromSet(new HashSet<>());
+
   public static FieldMask fromSet(Set<FieldPath> mask) {
     return new FieldMask(mask);
   }

firebase-firestore/src/test/java/com/google/firebase/firestore/local/LocalStoreTestCase.java

@@ -83,7 +83,6 @@
 import org.junit.After;
 import org.junit.Assert;
 import org.junit.Before;
-import org.junit.Ignore;
 import org.junit.Test;
 
 /**
@@ -154,7 +153,8 @@ private void udpateViews(int targetId, boolean fromCache) {
     notifyLocalViewChanges(viewChanges(targetId, fromCache, asList(), asList()));
   }
 
-  private void acknowledgeMutationWithTransform(long documentVersion, Object... transformResult) {
+  private void acknowledgeMutationWithTransformResults(
+      long documentVersion, Object... transformResult) {
     MutationBatch batch = batches.remove(0);
     SnapshotVersion version = version(documentVersion);
     List<MutationResult> mutationResults =
@@ -172,7 +172,7 @@ private void acknowledgeMutationWithTransform(long documentVersion, Object... tr
   }
 
   private void acknowledgeMutation(long documentVersion) {
-    acknowledgeMutationWithTransform(documentVersion, null);
+    acknowledgeMutationWithTransformResults(documentVersion, null);
   }
 
   private void rejectMutation() {
@@ -1074,7 +1074,7 @@ public void testHandlesSetMutationThenAckThenTransformThenAckThenTransform() {
     assertContains(doc("foo/bar", 1, map("sum", 1)).setHasLocalMutations());
     assertChanged(doc("foo/bar", 1, map("sum", 1)).setHasLocalMutations());
 
-    acknowledgeMutationWithTransform(2, 1);
+    acknowledgeMutationWithTransformResults(2, 1);
     assertChanged(doc("foo/bar", 2, map("sum", 1)).setHasCommittedMutations());
     assertContains(doc("foo/bar", 2, map("sum", 1)).setHasCommittedMutations());
 
@@ -1288,11 +1288,11 @@ public void testHandlesSetMutationThenTransformThenRemoteEventThenTransform() {
     assertChanged(doc("foo/bar", 2, map("sum", 3)).setHasLocalMutations());
     assertContains(doc("foo/bar", 2, map("sum", 3)).setHasLocalMutations());
 
-    acknowledgeMutationWithTransform(3, 1);
+    acknowledgeMutationWithTransformResults(3, 1);
     assertChanged(doc("foo/bar", 3, map("sum", 3)).setHasLocalMutations());
     assertContains(doc("foo/bar", 3, map("sum", 3)).setHasLocalMutations());
 
-    acknowledgeMutationWithTransform(4, 1339);
+    acknowledgeMutationWithTransformResults(4, 1339);
     assertChanged(doc("foo/bar", 4, map("sum", 1339)).setHasCommittedMutations());
     assertContains(doc("foo/bar", 4, map("sum", 1339)).setHasCommittedMutations());
   }
@@ -1337,7 +1337,7 @@ public void testHoldsBackTransforms() {
     assertChanged(
         doc("foo/bar", 2, map("sum", 1, "array_union", asList("foo"))).setHasLocalMutations());
 
-    acknowledgeMutationWithTransform(3, 1338, asList("bar", "foo"));
+    acknowledgeMutationWithTransformResults(3, 1338, asList("bar", "foo"));
     assertChanged(
         doc("foo/bar", 3, map("sum", 1338, "array_union", asList("bar", "foo")))
             .withReadTime(new SnapshotVersion(new Timestamp(0, 3000)))