--- /dev/null
+package org.apache.lucene.search;
+
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import org.apache.lucene.index.IndexReader;
+import org.apache.lucene.util.DocIdBitSet;
+import java.util.BitSet;
+
+public class MockFilter extends Filter {
+ private boolean wasCalled;
+
+ @Override
+ public DocIdSet getDocIdSet(IndexReader reader) {
+ wasCalled = true;
+ return new DocIdBitSet(new BitSet());
+ }
+
+ public void clear() {
+ wasCalled = false;
+ }
+
+ public boolean wasCalled() {
+ return wasCalled;
+ }
+}