resolve comments

Author: milaGGL

packages/firestore/src/local/local_store_impl.ts

@@ -601,7 +601,7 @@ export function localStoreApplyRemoteEventToLocalCache(
         let newTargetData = oldTargetData.withSequenceNumber(
           txn.currentSequenceNumber
         );
-        if (remoteEvent.targetMismatches.get(targetId) != null) {
+        if (remoteEvent.targetMismatches.get(targetId) !== null) {
           newTargetData = newTargetData
             .withResumeToken(
               ByteString.EMPTY_BYTE_STRING,

packages/firestore/src/local/target_data.ts

@@ -26,12 +26,14 @@ export const enum TargetPurpose {
   Listen,
 
   /**
-   * The query target was used to refill a query after an existence filter mismatch.
+   * The query target was used to refill a query after an existence filter
+   * mismatch.
    */
   ExistenceFilterMismatch,
 
   /**
-   * The query target was used if the query is the result of a false positive in the bloom filter.
+   * The query target was used if the query is the result of a false positive in
+   * the bloom filter.
    */
   ExistenceFilterMismatchBloom,
 

packages/firestore/src/remote/bloom_filter.ts

@@ -75,10 +75,6 @@ export class BloomFilter {
     this.bitCountInInteger = Integer.fromNumber(this.bitCount);
   }
 
-  isEmpty(): boolean {
-    return this.bitCount === 0;
-  }
-
   // Calculate the ith hash value based on the hashed 64bit integers,
   // and calculate its corresponding bit index in the bitmap to be checked.
   private getBitIndex(num1: Integer, num2: Integer, hashIndex: number): number {

packages/firestore/src/remote/remote_store.ts

@@ -611,10 +611,7 @@ function raiseWatchSnapshot(
     // Mark the target we send as being on behalf of an existence filter
     // mismatch, but don't actually retain that in listenTargets. This ensures
     // that we flag the first re-listen this way without impacting future
-    // listens of this target (that might happen e.g. on reconnect). The target
-    // purpose will be `ExistenceFilterMismatchBloom` if there is a bloom filter
-    // but it yield false positive result, otherwise, it will be set to
-    // `ExistenceFilterMismatch`.
+    // listens of this target (that might happen e.g. on reconnect).
     const requestTargetData = new TargetData(
       targetData.target,
       targetId,

packages/firestore/src/remote/watch_change.ts

@@ -499,7 +499,7 @@ export class WatchChangeAggregator {
       return BloomFilterApplicationStatus.Skipped;
     }
 
-    if (bloomFilter.isEmpty()) {
+    if (bloomFilter.bitCount === 0) {
       return BloomFilterApplicationStatus.Skipped;
     }
 

packages/firestore/test/unit/remote/remote_event.test.ts

@@ -431,6 +431,9 @@ describe('RemoteEvent', () => {
     expectTargetChangeEquals(event.targetChanges.get(1)!, expected);
   });
 
+  // TODO(Mila): Add test cases for existence filter with bloom filter, one will
+  // skip the re-query, one will yield false positive result and clears target
+  // mapping. b/272564458
   it('existence filters clears target mapping', () => {
     const targets = listens(1, 2);