Revert: Index-Free Queries (code, feature still disabled) (#727)

Author: schmidt-sebastian

firebase-firestore/ktx/src/test/java/com/google/firebase/firestore/TestUtil.java

@@ -117,8 +117,7 @@ public static QuerySnapshot querySnapshot(
             documentChanges,
             isFromCache,
             mutatedKeys,
-            /* synced= */ false,
-            /* didSyncStateChange= */ true,
+            true,
             /* excludesMetadataChanges= */ false);
     return new QuerySnapshot(query(path), viewSnapshot, FIRESTORE);
   }

firebase-firestore/src/androidTest/java/com/google/firebase/firestore/remote/RemoteStoreTest.java

@@ -24,7 +24,6 @@
 import com.google.firebase.firestore.local.LocalStore;
 import com.google.firebase.firestore.local.MemoryPersistence;
 import com.google.firebase.firestore.local.Persistence;
-import com.google.firebase.firestore.local.SimpleQueryEngine;
 import com.google.firebase.firestore.model.DocumentKey;
 import com.google.firebase.firestore.model.mutation.MutationBatchResult;
 import com.google.firebase.firestore.testutil.IntegrationTestUtil;
@@ -73,10 +72,9 @@ public ImmutableSortedSet<DocumentKey> getRemoteKeysForTarget(int targetId) {
         };
 
     FakeConnectivityMonitor connectivityMonitor = new FakeConnectivityMonitor();
-    SimpleQueryEngine queryEngine = new SimpleQueryEngine();
     Persistence persistence = MemoryPersistence.createEagerGcMemoryPersistence();
     persistence.start();
-    LocalStore localStore = new LocalStore(persistence, queryEngine, User.UNAUTHENTICATED);
+    LocalStore localStore = new LocalStore(persistence, User.UNAUTHENTICATED);
     RemoteStore remoteStore =
         new RemoteStore(callback, localStore, datastore, testQueue, connectivityMonitor);
 

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

@@ -37,9 +37,7 @@
 import com.google.firebase.firestore.local.LruGarbageCollector;
 import com.google.firebase.firestore.local.MemoryPersistence;
 import com.google.firebase.firestore.local.Persistence;
-import com.google.firebase.firestore.local.QueryEngine;
 import com.google.firebase.firestore.local.SQLitePersistence;
-import com.google.firebase.firestore.local.SimpleQueryEngine;
 import com.google.firebase.firestore.model.Document;
 import com.google.firebase.firestore.model.DocumentKey;
 import com.google.firebase.firestore.model.MaybeDocument;
@@ -268,9 +266,7 @@ private void initialize(Context context, User user, boolean usePersistence, long
     }
 
     persistence.start();
-    // TODO(index-free): Use IndexFreeQueryEngine/IndexedQueryEngine as appropriate.
-    QueryEngine queryEngine = new SimpleQueryEngine();
-    localStore = new LocalStore(persistence, queryEngine, user);
+    localStore = new LocalStore(persistence, user);
     if (gc != null) {
       lruScheduler = gc.newScheduler(asyncQueue, localStore);
       lruScheduler.start();

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

@@ -117,18 +117,6 @@ public boolean isCollectionGroupQuery() {
     return collectionGroup != null;
   }
 
-  /**
-   * Returns true if this query does not specify any query constraints that could remove results.
-   */
-  public boolean matchesAllDocuments() {
-    return filters.isEmpty()
-        && limit == NO_LIMIT
-        && startAt == null
-        && endAt == null
-        && (getExplicitOrderBy().isEmpty()
-            || (getExplicitOrderBy().size() == 1 && getFirstOrderByField().isKeyField()));
-  }
-
   /** The filters on the documents returned by the query. */
   public List<Filter> getFilters() {
     return filters;

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

@@ -86,7 +86,6 @@ public boolean onViewSnapshot(ViewSnapshot newSnapshot) {
               documentChanges,
               newSnapshot.isFromCache(),
               newSnapshot.getMutatedKeys(),
-              newSnapshot.isSynced(),
               newSnapshot.didSyncStateChange(),
               /* excludesMetadataChanges= */ true);
     }
@@ -172,7 +171,6 @@ private void raiseInitialEvent(ViewSnapshot snapshot) {
             snapshot.getDocuments(),
             snapshot.getMutatedKeys(),
             snapshot.isFromCache(),
-            snapshot.isSynced(),
             snapshot.excludesMetadataChanges());
     raisedInitialEvent = true;
     listener.onEvent(snapshot, null);

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

@@ -191,10 +191,9 @@ public int listen(Query query) {
   private ViewSnapshot initializeViewAndComputeSnapshot(QueryData queryData) {
     Query query = queryData.getQuery();
 
+    ImmutableSortedMap<DocumentKey, Document> docs = localStore.executeQuery(query);
     ImmutableSortedSet<DocumentKey> remoteKeys =
         localStore.getRemoteDocumentKeys(queryData.getTargetId());
-    ImmutableSortedMap<DocumentKey, Document> docs =
-        localStore.executeQuery(query, queryData, remoteKeys);
 
     View view = new View(query, remoteKeys);
     View.DocumentChanges viewDocChanges = view.computeDocChanges(docs);
@@ -531,8 +530,7 @@ private void emitNewSnapsAndNotifyLocalStore(
         // against the local store to make sure we didn't lose any good docs that had been past the
         // limit.
         ImmutableSortedMap<DocumentKey, Document> docs =
-            localStore.executeQuery(
-                queryView.getQuery(), /* queryData= */ null, DocumentKey.emptyKeySet());
+            localStore.executeQuery(queryView.getQuery());
         viewDocChanges = view.computeDocChanges(docs, viewDocChanges);
       }
       TargetChange targetChange =

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

@@ -311,7 +311,6 @@ public ViewChange applyChanges(DocumentChanges docChanges, TargetChange targetCh
               viewChanges,
               fromCache,
               docChanges.mutatedKeys,
-              synced,
               syncStatedChanged,
               /* excludesMetadataChanges= */ false);
     }

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

@@ -37,7 +37,6 @@ public enum SyncState {
   private final List<DocumentViewChange> changes;
   private final boolean isFromCache;
   private final ImmutableSortedSet<DocumentKey> mutatedKeys;
-  private final boolean synced;
   private final boolean didSyncStateChange;
   private boolean excludesMetadataChanges;
 
@@ -48,7 +47,6 @@ public ViewSnapshot(
       List<DocumentViewChange> changes,
       boolean isFromCache,
       ImmutableSortedSet<DocumentKey> mutatedKeys,
-      boolean synced,
       boolean didSyncStateChange,
       boolean excludesMetadataChanges) {
     this.query = query;
@@ -57,7 +55,6 @@ public ViewSnapshot(
     this.changes = changes;
     this.isFromCache = isFromCache;
     this.mutatedKeys = mutatedKeys;
-    this.synced = synced;
     this.didSyncStateChange = didSyncStateChange;
     this.excludesMetadataChanges = excludesMetadataChanges;
   }
@@ -68,7 +65,6 @@ public static ViewSnapshot fromInitialDocuments(
       DocumentSet documents,
       ImmutableSortedSet<DocumentKey> mutatedKeys,
       boolean fromCache,
-      boolean synced,
       boolean excludesMetadataChanges) {
     List<DocumentViewChange> viewChanges = new ArrayList<>();
     for (Document doc : documents) {
@@ -81,7 +77,6 @@ public static ViewSnapshot fromInitialDocuments(
         viewChanges,
         fromCache,
         mutatedKeys,
-        synced,
         /* didSyncStateChange= */ true,
         excludesMetadataChanges);
   }
@@ -90,10 +85,6 @@ public Query getQuery() {
     return query;
   }
 
-  public boolean isSynced() {
-    return synced;
-  }
-
   public DocumentSet getDocuments() {
     return documents;
   }
@@ -140,9 +131,6 @@ public final boolean equals(Object o) {
     if (isFromCache != that.isFromCache) {
       return false;
     }
-    if (synced != that.synced) {
-      return false;
-    }
     if (didSyncStateChange != that.didSyncStateChange) {
       return false;
     }
@@ -172,7 +160,6 @@ public int hashCode() {
     result = 31 * result + changes.hashCode();
     result = 31 * result + mutatedKeys.hashCode();
     result = 31 * result + (isFromCache ? 1 : 0);
-    result = 31 * result + (synced ? 1 : 0);
     result = 31 * result + (didSyncStateChange ? 1 : 0);
     result = 31 * result + (excludesMetadataChanges ? 1 : 0);
     return result;
@@ -192,8 +179,6 @@ public String toString() {
         + isFromCache
         + ", mutatedKeys="
         + mutatedKeys.size()
-        + ", synced="
-        + synced
         + ", didSyncStateChange="
         + didSyncStateChange
         + ", excludesMetadataChanges="