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Author: wu-hui

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

@@ -148,7 +148,7 @@ Map<DocumentKey, OverlayedDocument> getOverlayedDocuments(
    * @param docs The documents to compute views for. It also has the base version of the documents.
    * @param overlays The overlays that need to be applied to the given base version of the
    *     documents.
-   * @param existenceStateChanged A set of documents that might there existence states changed. This
+   * @param existenceStateChanged A set of documents whose existence states might have changed. This
    *     is used to determine if we need to re-calculate overlays from mutation queues.
    * @return A map represents the local documents view.
    */

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

@@ -102,6 +102,7 @@ public void applyToRemoteDocument(MutableDocument document, MutationBatchResult
   /**
    * Computes the local view of a document given all the mutations in this batch.
    *
+   * @param mutatedFields The document to be mutated.
    * @param mutatedFields Fields that are already mutated before applying the current one.
    * @return An {@link FieldMask} representing all the fields that are mutated.
    */

firebase-firestore/src/main/java/com/google/firebase/firestore/remote/RemoteSerializer.java

@@ -269,7 +269,7 @@ public com.google.firestore.v1.Write encodeMutation(Mutation mutation) {
       builder.setUpdate(encodeDocument(mutation.getKey(), ((SetMutation) mutation).getValue()));
     } else if (mutation instanceof PatchMutation) {
       builder.setUpdate(encodeDocument(mutation.getKey(), ((PatchMutation) mutation).getValue()));
-      builder.setUpdateMask(encodeDocumentMask(((PatchMutation) mutation).getFieldMask()));
+      builder.setUpdateMask(encodeDocumentMask((mutation.getFieldMask())));
     } else if (mutation instanceof DeleteMutation) {
       builder.setDelete(encodeKey(mutation.getKey()));
     } else if (mutation instanceof VerifyMutation) {