feat: track ModelQuery pending changes

14 files changed, 87 insertions, 48 deletions

diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/ViatraModelQuery.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/ViatraModelQuery.java
index ecac570b..677e3c7d 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/ViatraModelQuery.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/ViatraModelQuery.java
@@ -3,15 +3,14 @@ package tools.refinery.store.query.viatra;
 import tools.refinery.store.adapter.ModelAdapterBuilderFactory;
 import tools.refinery.store.model.ModelStoreBuilder;
 import tools.refinery.store.query.ModelQuery;
-import tools.refinery.store.query.ModelQueryAdapter;
 import tools.refinery.store.query.viatra.internal.ViatraModelQueryBuilderImpl;
 
-public final class ViatraModelQuery extends ModelAdapterBuilderFactory<ModelQueryAdapter, ViatraModelQueryStoreAdapter,
-                ViatraModelQueryBuilder> {
+public final class ViatraModelQuery extends ModelAdapterBuilderFactory<ViatraModelQueryAdapter,
+                ViatraModelQueryStoreAdapter, ViatraModelQueryBuilder> {
         public static final ViatraModelQuery ADAPTER = new ViatraModelQuery();
 
         private ViatraModelQuery() {
-                super(ModelQueryAdapter.class, ViatraModelQueryStoreAdapter.class, ViatraModelQueryBuilder.class);
+                super(ViatraModelQueryAdapter.class, ViatraModelQueryStoreAdapter.class, ViatraModelQueryBuilder.class);
                 extendsAdapter(ModelQuery.ADAPTER);
         }
 
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/ViatraModelQueryAdapter.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/ViatraModelQueryAdapter.java
new file mode 100644
index 00000000..7e21476b
--- /dev/null
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/ViatraModelQueryAdapter.java
@@ -0,0 +1,8 @@
+package tools.refinery.store.query.viatra;
+
+import tools.refinery.store.query.ModelQueryAdapter;
+
+public interface ViatraModelQueryAdapter extends ModelQueryAdapter {
+        @Override
+        ViatraModelQueryStoreAdapter getStoreAdapter();
+}
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/ViatraModelQueryStoreAdapter.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/ViatraModelQueryStoreAdapter.java
index d52575d2..1ee02f12 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/ViatraModelQueryStoreAdapter.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/ViatraModelQueryStoreAdapter.java
@@ -1,8 +1,12 @@
 package tools.refinery.store.query.viatra;
 
 import org.eclipse.viatra.query.runtime.api.ViatraQueryEngineOptions;
+import tools.refinery.store.model.Model;
 import tools.refinery.store.query.ModelQueryStoreAdapter;
 
 public interface ViatraModelQueryStoreAdapter extends ModelQueryStoreAdapter {
         ViatraQueryEngineOptions getEngineOptions();
+
+        @Override
+        ViatraModelQueryAdapter createModelAdapter(Model model);
 }
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/RelationalScope.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/RelationalScope.java
index b4d43ef8..8328e759 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/RelationalScope.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/RelationalScope.java
@@ -5,25 +5,18 @@ import org.eclipse.viatra.query.runtime.api.ViatraQueryEngine;
 import org.eclipse.viatra.query.runtime.api.scope.IEngineContext;
 import org.eclipse.viatra.query.runtime.api.scope.IIndexingErrorListener;
 import org.eclipse.viatra.query.runtime.api.scope.QueryScope;
-import org.eclipse.viatra.query.runtime.matchers.context.IInputKey;
-import tools.refinery.store.model.Model;
 import tools.refinery.store.query.viatra.internal.context.RelationalEngineContext;
-import tools.refinery.store.query.view.AnyRelationView;
-
-import java.util.Map;
 
 public class RelationalScope extends QueryScope {
-        private final Model model;
-        private final Map<AnyRelationView, IInputKey> relationViews;
+        private final ViatraModelQueryAdapterImpl adapter;
 
-        public RelationalScope(Model model, Map<AnyRelationView, IInputKey> relationViews) {
-                this.model = model;
-                this.relationViews = relationViews;
+        public RelationalScope(ViatraModelQueryAdapterImpl adapter) {
+                this.adapter = adapter;
         }
 
         @Override
         protected IEngineContext createEngineContext(ViatraQueryEngine engine, IIndexingErrorListener errorListener,
                                                                                                  Logger logger) {
-                return new RelationalEngineContext(model, relationViews);
+                return new RelationalEngineContext(adapter);
         }
 }
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/ViatraModelQueryAdapterImpl.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/ViatraModelQueryAdapterImpl.java
index 810d2c32..039f46fa 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/ViatraModelQueryAdapterImpl.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/ViatraModelQueryAdapterImpl.java
@@ -8,15 +8,17 @@ import org.eclipse.viatra.query.runtime.matchers.backend.IQueryBackend;
 import org.eclipse.viatra.query.runtime.matchers.backend.IQueryBackendFactory;
 import tools.refinery.store.model.Model;
 import tools.refinery.store.query.DNF;
-import tools.refinery.store.query.ModelQueryAdapter;
-import tools.refinery.store.query.ModelQueryStoreAdapter;
 import tools.refinery.store.query.ResultSet;
+import tools.refinery.store.query.viatra.ViatraModelQueryAdapter;
 
 import java.lang.invoke.MethodHandle;
 import java.lang.invoke.MethodHandles;
-import java.util.*;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
 
-public class ViatraModelQueryAdapterImpl implements ModelQueryAdapter {
+public class ViatraModelQueryAdapterImpl implements ViatraModelQueryAdapter {
         private static final String DELAY_MESSAGE_DELIVERY_FIELD_NAME = "delayMessageDelivery";
         private static final String QUERY_BACKENDS_FIELD_NAME = "queryBackends";
 
@@ -26,11 +28,12 @@ public class ViatraModelQueryAdapterImpl implements ModelQueryAdapter {
         private final MethodHandle setUpdatePropagationDelayedHandle;
         private final MethodHandle getQueryBackendsHandle;
         private final Map<DNF, ResultSet> resultSets;
+        private boolean pendingChanges;
 
         ViatraModelQueryAdapterImpl(Model model, ViatraModelQueryStoreAdapterImpl storeAdapter) {
                 this.model = model;
                 this.storeAdapter = storeAdapter;
-                var scope = new RelationalScope(model, storeAdapter.getInputKeys());
+                var scope = new RelationalScope(this);
                 queryEngine = (ViatraQueryEngineImpl) AdvancedViatraQueryEngine.createUnmanagedEngine(scope);
 
                 try {
@@ -87,7 +90,7 @@ public class ViatraModelQueryAdapterImpl implements ModelQueryAdapter {
         }
 
         @Override
-        public ModelQueryStoreAdapter getStoreAdapter() {
+        public ViatraModelQueryStoreAdapterImpl getStoreAdapter() {
                 return storeAdapter;
         }
 
@@ -101,10 +104,24 @@ public class ViatraModelQueryAdapterImpl implements ModelQueryAdapter {
         }
 
         @Override
+        public boolean hasPendingChanges() {
+                return pendingChanges;
+        }
+
+        public void markAsPending() {
+                if (!pendingChanges) {
+                        pendingChanges = true;
+                }
+        }
+
+        @Override
         public void flushChanges() {
                 if (!queryEngine.isUpdatePropagationDelayed()) {
                         throw new IllegalStateException("Trying to flush changes while changes are already being flushed");
                 }
+                if (!pendingChanges) {
+                        return;
+                }
                 setUpdatePropagationDelayed(false);
                 try {
                         for (var queryBackend : getQueryBackends()) {
@@ -113,5 +130,6 @@ public class ViatraModelQueryAdapterImpl implements ModelQueryAdapter {
                 } finally {
                         setUpdatePropagationDelayed(true);
                 }
+                pendingChanges = false;
         }
 }
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/ViatraModelQueryStoreAdapterImpl.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/ViatraModelQueryStoreAdapterImpl.java
index 69f1f146..394e407e 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/ViatraModelQueryStoreAdapterImpl.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/ViatraModelQueryStoreAdapterImpl.java
@@ -37,7 +37,7 @@ public class ViatraModelQueryStoreAdapterImpl implements ViatraModelQueryStoreAd
                 return inputKeys.keySet();
         }
 
-        Map<AnyRelationView, IInputKey> getInputKeys() {
+        public Map<AnyRelationView, IInputKey> getInputKeys() {
                 return inputKeys;
         }
 
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/context/RelationalEngineContext.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/context/RelationalEngineContext.java
index 3bad01b9..28bc69d0 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/context/RelationalEngineContext.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/context/RelationalEngineContext.java
@@ -2,19 +2,15 @@ package tools.refinery.store.query.viatra.internal.context;
 
 import org.eclipse.viatra.query.runtime.api.scope.IBaseIndex;
 import org.eclipse.viatra.query.runtime.api.scope.IEngineContext;
-import org.eclipse.viatra.query.runtime.matchers.context.IInputKey;
 import org.eclipse.viatra.query.runtime.matchers.context.IQueryRuntimeContext;
-import tools.refinery.store.model.Model;
-import tools.refinery.store.query.view.AnyRelationView;
-
-import java.util.Map;
+import tools.refinery.store.query.viatra.internal.ViatraModelQueryAdapterImpl;
 
 public class RelationalEngineContext implements IEngineContext {
         private final IBaseIndex baseIndex = new DummyBaseIndexer();
         private final RelationalRuntimeContext runtimeContext;
 
-        public RelationalEngineContext(Model model, Map< AnyRelationView, IInputKey> inputKeys) {
-                runtimeContext = new RelationalRuntimeContext(model, inputKeys);
+        public RelationalEngineContext(ViatraModelQueryAdapterImpl adapter) {
+                runtimeContext = new RelationalRuntimeContext(adapter);
         }
 
         @Override
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/context/RelationalRuntimeContext.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/context/RelationalRuntimeContext.java
index 71ab5cb4..01d20d3e 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/context/RelationalRuntimeContext.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/context/RelationalRuntimeContext.java
@@ -7,13 +7,13 @@ import org.eclipse.viatra.query.runtime.matchers.tuple.TupleMask;
 import org.eclipse.viatra.query.runtime.matchers.tuple.Tuples;
 import org.eclipse.viatra.query.runtime.matchers.util.Accuracy;
 import tools.refinery.store.model.Model;
+import tools.refinery.store.query.viatra.internal.ViatraModelQueryAdapterImpl;
 import tools.refinery.store.query.viatra.internal.pquery.RelationViewWrapper;
 import tools.refinery.store.query.viatra.internal.update.ModelUpdateListener;
 import tools.refinery.store.query.view.AnyRelationView;
 
 import java.lang.reflect.InvocationTargetException;
 import java.util.Iterator;
-import java.util.Map;
 import java.util.Optional;
 import java.util.concurrent.Callable;
 
@@ -27,10 +27,10 @@ public class RelationalRuntimeContext implements IQueryRuntimeContext {
 
         private final Model model;
 
-        RelationalRuntimeContext(Model model, Map<AnyRelationView, IInputKey> inputKeys) {
-                this.model = model;
-                metaContext = new RelationalQueryMetaContext(inputKeys);
-                modelUpdateListener = new ModelUpdateListener(model, inputKeys.keySet());
+        RelationalRuntimeContext(ViatraModelQueryAdapterImpl adapter) {
+                model = adapter.getModel();
+                metaContext = new RelationalQueryMetaContext(adapter.getStoreAdapter().getInputKeys());
+                modelUpdateListener = new ModelUpdateListener(adapter);
         }
 
         @Override
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/ModelUpdateListener.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/ModelUpdateListener.java
index 1ae3daa7..8a467066 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/ModelUpdateListener.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/ModelUpdateListener.java
@@ -3,26 +3,27 @@ package tools.refinery.store.query.viatra.internal.update;
 import org.eclipse.viatra.query.runtime.matchers.context.IInputKey;
 import org.eclipse.viatra.query.runtime.matchers.context.IQueryRuntimeContextListener;
 import org.eclipse.viatra.query.runtime.matchers.tuple.ITuple;
-import tools.refinery.store.model.Model;
+import tools.refinery.store.query.viatra.internal.ViatraModelQueryAdapterImpl;
 import tools.refinery.store.query.view.AnyRelationView;
 import tools.refinery.store.query.view.RelationView;
 
-import java.util.Collection;
 import java.util.HashMap;
 import java.util.Map;
 
 public class ModelUpdateListener {
         private final Map<AnyRelationView, RelationViewUpdateListener<?>> relationViewUpdateListeners;
 
-        public ModelUpdateListener(Model model, Collection<AnyRelationView> relationViews) {
+        public ModelUpdateListener(ViatraModelQueryAdapterImpl adapter) {
+                var relationViews = adapter.getStoreAdapter().getInputKeys().keySet();
                 relationViewUpdateListeners = new HashMap<>(relationViews.size());
                 for (var relationView : relationViews) {
-                        registerView(model, (RelationView<?>) relationView);
+                        registerView(adapter, (RelationView<?>) relationView);
                 }
         }
 
-        private <T> void registerView(Model model, RelationView<T> relationView) {
-                var listener = RelationViewUpdateListener.of(relationView);
+        private <T> void registerView(ViatraModelQueryAdapterImpl adapter, RelationView<T> relationView) {
+                var listener = RelationViewUpdateListener.of(adapter, relationView);
+                var model = adapter.getModel();
                 var interpretation = model.getInterpretation(relationView.getSymbol());
                 interpretation.addListener(listener, true);
                 relationViewUpdateListeners.put(relationView, listener);
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/RelationViewUpdateListener.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/RelationViewUpdateListener.java
index e0d44e34..bf6b4197 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/RelationViewUpdateListener.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/RelationViewUpdateListener.java
@@ -5,6 +5,7 @@ import org.eclipse.viatra.query.runtime.matchers.context.IQueryRuntimeContextLis
 import org.eclipse.viatra.query.runtime.matchers.tuple.ITuple;
 import org.eclipse.viatra.query.runtime.matchers.tuple.Tuple;
 import tools.refinery.store.model.InterpretationListener;
+import tools.refinery.store.query.viatra.internal.ViatraModelQueryAdapterImpl;
 import tools.refinery.store.query.view.RelationView;
 import tools.refinery.store.query.view.TuplePreservingRelationView;
 
@@ -12,8 +13,13 @@ import java.util.ArrayList;
 import java.util.List;
 
 public abstract class RelationViewUpdateListener<T> implements InterpretationListener<T> {
+        private final ViatraModelQueryAdapterImpl adapter;
         private final List<RelationViewFilter> filters = new ArrayList<>();
 
+        protected RelationViewUpdateListener(ViatraModelQueryAdapterImpl adapter) {
+                this.adapter = adapter;
+        }
+
         public void addFilter(IInputKey inputKey, ITuple seed, IQueryRuntimeContextListener listener) {
                 filters.add(new RelationViewFilter(inputKey, seed, listener));
         }
@@ -23,6 +29,7 @@ public abstract class RelationViewUpdateListener<T> implements InterpretationLis
         }
 
         protected void processUpdate(Tuple tuple, boolean isInsertion) {
+                adapter.markAsPending();
                 int size = filters.size();
                 // Use a for loop instead of a for-each loop to avoid <code>Iterator</code> allocation overhead.
                 //noinspection ForLoopReplaceableByForEach
@@ -31,10 +38,11 @@ public abstract class RelationViewUpdateListener<T> implements InterpretationLis
                 }
         }
 
-        public static <T> RelationViewUpdateListener<T> of(RelationView<T> relationView) {
+        public static <T> RelationViewUpdateListener<T> of(ViatraModelQueryAdapterImpl adapter,
+                                                                                                           RelationView<T> relationView) {
                 if (relationView instanceof TuplePreservingRelationView<T> tuplePreservingRelationView) {
-                        return new TuplePreservingRelationViewUpdateListener<>(tuplePreservingRelationView);
+                        return new TuplePreservingRelationViewUpdateListener<>(adapter, tuplePreservingRelationView);
                 }
-                return new TupleChangingRelationViewUpdateListener<>(relationView);
+                return new TupleChangingRelationViewUpdateListener<>(adapter, relationView);
         }
 }
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/TupleChangingRelationViewUpdateListener.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/TupleChangingRelationViewUpdateListener.java
index 0d43eac1..14142884 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/TupleChangingRelationViewUpdateListener.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/TupleChangingRelationViewUpdateListener.java
@@ -1,6 +1,7 @@
 package tools.refinery.store.query.viatra.internal.update;
 
 import org.eclipse.viatra.query.runtime.matchers.tuple.Tuples;
+import tools.refinery.store.query.viatra.internal.ViatraModelQueryAdapterImpl;
 import tools.refinery.store.query.view.RelationView;
 import tools.refinery.store.tuple.Tuple;
 
@@ -9,8 +10,9 @@ import java.util.Arrays;
 public class TupleChangingRelationViewUpdateListener<T> extends RelationViewUpdateListener<T> {
         private final RelationView<T> relationView;
 
-        TupleChangingRelationViewUpdateListener(RelationView<T> relationView) {
-                this.relationView = relationView;
+        TupleChangingRelationViewUpdateListener(ViatraModelQueryAdapterImpl adapter, RelationView<T> relationView) {
+        super(adapter);
+        this.relationView = relationView;
         }
 
         @Override
diff --git a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/TuplePreservingRelationViewUpdateListener.java b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/TuplePreservingRelationViewUpdateListener.java
index 9c3ef61c..288e018a 100644
--- a/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/TuplePreservingRelationViewUpdateListener.java
+++ b/subprojects/store-query-viatra/src/main/java/tools/refinery/store/query/viatra/internal/update/TuplePreservingRelationViewUpdateListener.java
@@ -1,14 +1,17 @@
 package tools.refinery.store.query.viatra.internal.update;
 
 import org.eclipse.viatra.query.runtime.matchers.tuple.Tuples;
+import tools.refinery.store.query.viatra.internal.ViatraModelQueryAdapterImpl;
 import tools.refinery.store.query.view.TuplePreservingRelationView;
 import tools.refinery.store.tuple.Tuple;
 
 public class TuplePreservingRelationViewUpdateListener<T> extends RelationViewUpdateListener<T> {
         private final TuplePreservingRelationView<T> view;
 
-        TuplePreservingRelationViewUpdateListener(TuplePreservingRelationView<T> view) {
-                this.view = view;
+        TuplePreservingRelationViewUpdateListener(ViatraModelQueryAdapterImpl adapter,
+                                                                                          TuplePreservingRelationView<T> view) {
+        super(adapter);
+        this.view = view;
         }
 
         @Override
diff --git a/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/QueryTransactionTest.java b/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/QueryTransactionTest.java
index 49087a8d..ec2e7647 100644
--- a/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/QueryTransactionTest.java
+++ b/subprojects/store-query-viatra/src/test/java/tools/refinery/store/query/viatra/QueryTransactionTest.java
@@ -10,7 +10,7 @@ import tools.refinery.store.query.view.KeyOnlyRelationView;
 import tools.refinery.store.representation.Symbol;
 import tools.refinery.store.tuple.Tuple;
 
-import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.*;
 
 class QueryTransactionTest {
         @Test
@@ -38,6 +38,7 @@ class QueryTransactionTest {
                 var predicateResultSet = queryEngine.getResultSet(predicate);
 
                 assertEquals(0, predicateResultSet.countResults());
+                assertFalse(queryEngine.hasPendingChanges());
 
                 personInterpretation.put(Tuple.of(0), true);
                 personInterpretation.put(Tuple.of(1), true);
@@ -46,14 +47,18 @@ class QueryTransactionTest {
                 assetInterpretation.put(Tuple.of(2), true);
 
                 assertEquals(0, predicateResultSet.countResults());
+                assertTrue(queryEngine.hasPendingChanges());
 
                 queryEngine.flushChanges();
                 assertEquals(2, predicateResultSet.countResults());
+                assertFalse(queryEngine.hasPendingChanges());
 
                 personInterpretation.put(Tuple.of(4), true);
                 assertEquals(2, predicateResultSet.countResults());
+                assertTrue(queryEngine.hasPendingChanges());
 
                 queryEngine.flushChanges();
                 assertEquals(3, predicateResultSet.countResults());
+                assertFalse(queryEngine.hasPendingChanges());
         }
 }
diff --git a/subprojects/store/src/main/java/tools/refinery/store/query/ModelQueryAdapter.java b/subprojects/store/src/main/java/tools/refinery/store/query/ModelQueryAdapter.java
index d0cdf02d..7449e39b 100644
--- a/subprojects/store/src/main/java/tools/refinery/store/query/ModelQueryAdapter.java
+++ b/subprojects/store/src/main/java/tools/refinery/store/query/ModelQueryAdapter.java
@@ -7,5 +7,7 @@ public interface ModelQueryAdapter extends ModelAdapter {
 
         ResultSet getResultSet(DNF query);
 
+        boolean hasPendingChanges();
+
         void flushChanges();
 }