Fix bug that omitted sending change twice when serving multiple queries

Bug: Issue 11467
Change-Id: I2573e29f5bd0f7672111f05dffbd099ccdac837e

java/com/google/gerrit/server/change/ChangeJson.java

diff --git a/java/com/google/gerrit/server/change/ChangeJson.java b/java/com/google/gerrit/server/change/ChangeJson.java
index a3c2e92..d50e740 100644
--- a/java/com/google/gerrit/server/change/ChangeJson.java
+++ b/java/com/google/gerrit/server/change/ChangeJson.java
@@ -418,6 +418,7 @@
       for (ChangeData cd : changes) {
         ChangeInfo i = cache.get(cd.getId());
         if (i != null) {
+          changeInfos.add(i);
           continue;
         }
         try {

javatests/com/google/gerrit/acceptance/api/change/QueryChangeIT.java

diff --git a/javatests/com/google/gerrit/acceptance/api/change/QueryChangeIT.java b/javatests/com/google/gerrit/acceptance/api/change/QueryChangeIT.java
new file mode 100644
index 0000000..76166e1
--- /dev/null
+++ b/javatests/com/google/gerrit/acceptance/api/change/QueryChangeIT.java
@@ -0,0 +1,61 @@
+// Copyright (C) 2019 The Android Open Source Project
+//
+// Licensed 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.
+
+package com.google.gerrit.acceptance.api.change;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import com.google.common.collect.ImmutableList;
+import com.google.gerrit.acceptance.AbstractDaemonTest;
+import com.google.gerrit.acceptance.NoHttpd;
+import com.google.gerrit.extensions.common.ChangeInfo;
+import com.google.gerrit.extensions.restapi.TopLevelResource;
+import com.google.gerrit.server.restapi.change.QueryChanges;
+import com.google.inject.Inject;
+import com.google.inject.Provider;
+import java.util.List;
+import org.junit.Test;
+
+@NoHttpd
+public class QueryChangeIT extends AbstractDaemonTest {
+
+  @Inject private Provider<QueryChanges> queryChangesProvider;
+
+  @Test
+  @SuppressWarnings("unchecked")
+  public void multipleQueriesInOneRequestCanContainSameChange() throws Exception {
+    String cId1 = createChange().getChangeId();
+    String cId2 = createChange().getChangeId();
+    int numericId1 = gApi.changes().id(cId1).get()._number;
+    int numericId2 = gApi.changes().id(cId2).get()._number;
+
+    gApi.changes().id(cId2).setWorkInProgress();
+
+    QueryChanges queryChanges = queryChangesProvider.get();
+
+    queryChanges.addQuery("is:open");
+    queryChanges.addQuery("is:wip");
+
+    List<List<ChangeInfo>> result =
+        (List<List<ChangeInfo>>) queryChanges.apply(TopLevelResource.INSTANCE).value();
+    assertThat(result).hasSize(2);
+    assertThat(result.get(0)).hasSize(2);
+    assertThat(result.get(1)).hasSize(1);
+
+    List<Integer> firstResultIds =
+        ImmutableList.of(result.get(0).get(0)._number, result.get(0).get(1)._number);
+    assertThat(firstResultIds).containsExactly(numericId1, numericId2);
+    assertThat(result.get(1).get(0)._number).isEqualTo(numericId2);
+  }
+}