diff --git a/Documentation/rest-api-changes.txt b/Documentation/rest-api-changes.txt
index 8992f86..65275bd 100644
--- a/Documentation/rest-api-changes.txt
+++ b/Documentation/rest-api-changes.txt
@@ -8253,6 +8253,7 @@
 ancestry, where the oldest ancestor is the first.
 |`contains_git_conflicts`  ||Whether any of the rebased changes has conflicts
 due to rebasing.
+|===========================
 
 [[related-change-and-commit-info]]
 === RelatedChangeAndCommitInfo
diff --git a/contrib/git-gc-preserve b/contrib/git-gc-preserve
index f3946ab..a886721 100755
--- a/contrib/git-gc-preserve
+++ b/contrib/git-gc-preserve
@@ -67,6 +67,7 @@
   test -f "$LOCKFILE" || touch "$LOCKFILE"
   exec 9> "$LOCKFILE"
   if flock -nx 9; then
+    echo -n "$$ $USERNAME@$HOSTNAME" >&9
     trap unlock EXIT
   else
     echo "$0 is already running"
diff --git a/java/com/google/gerrit/extensions/common/ChangeInfoDiffer.java b/java/com/google/gerrit/extensions/common/ChangeInfoDiffer.java
index 24182cc..51c35dc 100644
--- a/java/com/google/gerrit/extensions/common/ChangeInfoDiffer.java
+++ b/java/com/google/gerrit/extensions/common/ChangeInfoDiffer.java
@@ -150,16 +150,17 @@
   /** Returns {@code null} if nothing has been added to {@code oldCollection} */
   @Nullable
   private static ImmutableList<?> getAddedForCollection(
-      Collection<?> oldCollection, Collection<?> newCollection) {
-    ImmutableList<?> notInOldCollection = getAdditions(oldCollection, newCollection);
+      @Nullable Collection<?> oldCollection, Collection<?> newCollection) {
+    ImmutableList<?> notInOldCollection = getAdditionsForCollection(oldCollection, newCollection);
     return notInOldCollection.isEmpty() ? null : notInOldCollection;
   }
 
   @Nullable
-  private static ImmutableList<Object> getAdditions(
-      Collection<?> oldCollection, Collection<?> newCollection) {
-    if (oldCollection == null)
-      return newCollection != null ? ImmutableList.copyOf(newCollection) : null;
+  private static ImmutableList<Object> getAdditionsForCollection(
+      @Nullable Collection<?> oldCollection, Collection<?> newCollection) {
+    if (oldCollection == null) {
+      return ImmutableList.copyOf(newCollection);
+    }
 
     Map<Object, List<Object>> duplicatesMap = newCollection.stream().collect(groupingBy(v -> v));
     oldCollection.forEach(
@@ -173,7 +174,18 @@
 
   /** Returns {@code null} if nothing has been added to {@code oldMap} */
   @Nullable
-  private static ImmutableMap<Object, Object> getAddedForMap(Map<?, ?> oldMap, Map<?, ?> newMap) {
+  private static ImmutableMap<Object, Object> getAddedForMap(
+      @Nullable Map<?, ?> oldMap, Map<?, ?> newMap) {
+    ImmutableMap<Object, Object> notInOldMap = getAdditionsForMap(oldMap, newMap);
+    return notInOldMap.isEmpty() ? null : notInOldMap;
+  }
+
+  @Nullable
+  private static ImmutableMap<Object, Object> getAdditionsForMap(
+      @Nullable Map<?, ?> oldMap, Map<?, ?> newMap) {
+    if (oldMap == null) {
+      return ImmutableMap.copyOf(newMap);
+    }
     ImmutableMap.Builder<Object, Object> additionsBuilder = ImmutableMap.builder();
     for (Map.Entry<?, ?> entry : newMap.entrySet()) {
       Object added = getAdded(oldMap.get(entry.getKey()), entry.getValue());
@@ -181,8 +193,7 @@
         additionsBuilder.put(entry.getKey(), added);
       }
     }
-    ImmutableMap<Object, Object> additions = additionsBuilder.build();
-    return additions.isEmpty() ? null : additions;
+    return additionsBuilder.build();
   }
 
   private static Object get(Field field, Object obj) {
diff --git a/java/com/google/gerrit/httpd/init/WebAppInitializer.java b/java/com/google/gerrit/httpd/init/WebAppInitializer.java
index 0073ec2..df2c5cb 100644
--- a/java/com/google/gerrit/httpd/init/WebAppInitializer.java
+++ b/java/com/google/gerrit/httpd/init/WebAppInitializer.java
@@ -55,6 +55,7 @@
 import com.google.gerrit.server.account.externalids.ExternalIdCaseSensitivityMigrator;
 import com.google.gerrit.server.api.GerritApiModule;
 import com.google.gerrit.server.api.PluginApiModule;
+import com.google.gerrit.server.api.projects.ProjectQueryBuilderModule;
 import com.google.gerrit.server.audit.AuditModule;
 import com.google.gerrit.server.cache.h2.H2CacheModule;
 import com.google.gerrit.server.cache.mem.DefaultMemoryCacheModule;
@@ -308,6 +309,7 @@
     modules.add(new MimeUtil2Module());
     modules.add(cfgInjector.getInstance(GerritGlobalModule.class));
     modules.add(new GerritApiModule());
+    modules.add(new ProjectQueryBuilderModule());
     modules.add(new PluginApiModule());
     modules.add(new SearchingChangeCacheImplModule());
     modules.add(new InternalAccountDirectoryModule());
diff --git a/java/com/google/gerrit/pgm/Daemon.java b/java/com/google/gerrit/pgm/Daemon.java
index 75891fe..0342fe5 100644
--- a/java/com/google/gerrit/pgm/Daemon.java
+++ b/java/com/google/gerrit/pgm/Daemon.java
@@ -64,6 +64,7 @@
 import com.google.gerrit.server.account.externalids.ExternalIdCaseSensitivityMigrator;
 import com.google.gerrit.server.api.GerritApiModule;
 import com.google.gerrit.server.api.PluginApiModule;
+import com.google.gerrit.server.api.projects.ProjectQueryBuilderModule;
 import com.google.gerrit.server.audit.AuditModule;
 import com.google.gerrit.server.cache.h2.H2CacheModule;
 import com.google.gerrit.server.cache.mem.DefaultMemoryCacheModule;
@@ -446,6 +447,7 @@
     modules.add(new MimeUtil2Module());
     modules.add(cfgInjector.getInstance(GerritGlobalModule.class));
     modules.add(new GerritApiModule());
+    modules.add(new ProjectQueryBuilderModule());
     modules.add(new PluginApiModule());
 
     modules.add(new SearchingChangeCacheImplModule(replica));
diff --git a/java/com/google/gerrit/server/account/AccountsUpdate.java b/java/com/google/gerrit/server/account/AccountsUpdate.java
index 8d5fea4..d6ea294 100644
--- a/java/com/google/gerrit/server/account/AccountsUpdate.java
+++ b/java/com/google/gerrit/server/account/AccountsUpdate.java
@@ -202,7 +202,6 @@
   private ExternalIdNotes externalIdNotes;
 
   @AssistedInject
-  @SuppressWarnings("BindingAnnotationWithoutInject")
   AccountsUpdate(
       GitRepositoryManager repoManager,
       GitReferenceUpdated gitRefUpdated,
@@ -228,7 +227,6 @@
   }
 
   @AssistedInject
-  @SuppressWarnings("BindingAnnotationWithoutInject")
   AccountsUpdate(
       GitRepositoryManager repoManager,
       GitReferenceUpdated gitRefUpdated,
diff --git a/java/com/google/gerrit/server/api/projects/ProjectQueryBuilderModule.java b/java/com/google/gerrit/server/api/projects/ProjectQueryBuilderModule.java
new file mode 100644
index 0000000..8ed1175
--- /dev/null
+++ b/java/com/google/gerrit/server/api/projects/ProjectQueryBuilderModule.java
@@ -0,0 +1,26 @@
+// Copyright (C) 2023 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.server.api.projects;
+
+import com.google.gerrit.server.query.project.ProjectQueryBuilder;
+import com.google.gerrit.server.query.project.ProjectQueryBuilderImpl;
+import com.google.inject.AbstractModule;
+
+public class ProjectQueryBuilderModule extends AbstractModule {
+  @Override
+  protected void configure() {
+    bind(ProjectQueryBuilder.class).to(ProjectQueryBuilderImpl.class);
+  }
+}
diff --git a/java/com/google/gerrit/server/group/db/GroupsUpdate.java b/java/com/google/gerrit/server/group/db/GroupsUpdate.java
index c0c934b..87d8db1 100644
--- a/java/com/google/gerrit/server/group/db/GroupsUpdate.java
+++ b/java/com/google/gerrit/server/group/db/GroupsUpdate.java
@@ -115,7 +115,6 @@
   private final RetryHelper retryHelper;
 
   @AssistedInject
-  @SuppressWarnings("BindingAnnotationWithoutInject")
   GroupsUpdate(
       GitRepositoryManager repoManager,
       AllUsersName allUsersName,
@@ -150,7 +149,6 @@
   }
 
   @AssistedInject
-  @SuppressWarnings("BindingAnnotationWithoutInject")
   GroupsUpdate(
       GitRepositoryManager repoManager,
       AllUsersName allUsersName,
@@ -185,7 +183,6 @@
         Optional.of(currentUser));
   }
 
-  @SuppressWarnings("BindingAnnotationWithoutInject")
   private GroupsUpdate(
       GitRepositoryManager repoManager,
       AllUsersName allUsersName,
diff --git a/java/com/google/gerrit/server/project/PeriodicProjectListCacheWarmer.java b/java/com/google/gerrit/server/project/PeriodicProjectListCacheWarmer.java
index 85a3ab9..df2e1cf 100644
--- a/java/com/google/gerrit/server/project/PeriodicProjectListCacheWarmer.java
+++ b/java/com/google/gerrit/server/project/PeriodicProjectListCacheWarmer.java
@@ -92,7 +92,6 @@
   }
 
   @Override
-  @SuppressWarnings("CheckReturnValue")
   public void run() {
     logger.atFine().log("Loading project_list cache");
     cache.refreshProjectList();
diff --git a/java/com/google/gerrit/server/query/project/ProjectQueryBuilder.java b/java/com/google/gerrit/server/query/project/ProjectQueryBuilder.java
index d234546..edb12ec 100644
--- a/java/com/google/gerrit/server/query/project/ProjectQueryBuilder.java
+++ b/java/com/google/gerrit/server/query/project/ProjectQueryBuilder.java
@@ -1,4 +1,4 @@
-// Copyright (C) 2017 The Android Open Source Project
+// Copyright (C) 2023 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.
@@ -14,93 +14,21 @@
 
 package com.google.gerrit.server.query.project;
 
-import com.google.common.base.Strings;
-import com.google.common.collect.Lists;
-import com.google.common.primitives.Ints;
-import com.google.gerrit.entities.Project;
-import com.google.gerrit.extensions.client.ProjectState;
 import com.google.gerrit.index.project.ProjectData;
-import com.google.gerrit.index.query.LimitPredicate;
 import com.google.gerrit.index.query.Predicate;
-import com.google.gerrit.index.query.QueryBuilder;
 import com.google.gerrit.index.query.QueryParseException;
-import com.google.inject.Inject;
 import java.util.List;
 
-/** Parses a query string meant to be applied to project objects. */
-public class ProjectQueryBuilder extends QueryBuilder<ProjectData, ProjectQueryBuilder> {
-  public static final String FIELD_LIMIT = "limit";
+/**
+ * Provides methods required for parsing projects queries.
+ *
+ * <p>Internally (at google), this interface has a different implementation, comparing to upstream.
+ */
+public interface ProjectQueryBuilder {
+  String FIELD_LIMIT = "limit";
 
-  private static final QueryBuilder.Definition<ProjectData, ProjectQueryBuilder> mydef =
-      new QueryBuilder.Definition<>(ProjectQueryBuilder.class);
-
-  @Inject
-  ProjectQueryBuilder() {
-    super(mydef, null);
-  }
-
-  @Operator
-  public Predicate<ProjectData> name(String name) {
-    return ProjectPredicates.name(Project.nameKey(name));
-  }
-
-  @Operator
-  public Predicate<ProjectData> parent(String parentName) {
-    return ProjectPredicates.parent(Project.nameKey(parentName));
-  }
-
-  @Operator
-  public Predicate<ProjectData> inname(String namePart) {
-    if (namePart.isEmpty()) {
-      return name(namePart);
-    }
-    return ProjectPredicates.inname(namePart);
-  }
-
-  @Operator
-  public Predicate<ProjectData> description(String description) throws QueryParseException {
-    if (Strings.isNullOrEmpty(description)) {
-      throw error("description operator requires a value");
-    }
-
-    return ProjectPredicates.description(description);
-  }
-
-  @Operator
-  public Predicate<ProjectData> state(String state) throws QueryParseException {
-    if (Strings.isNullOrEmpty(state)) {
-      throw error("state operator requires a value");
-    }
-    ProjectState parsedState;
-    try {
-      parsedState = ProjectState.valueOf(state.replace('-', '_').toUpperCase());
-    } catch (IllegalArgumentException e) {
-      throw error("state operator must be either 'active' or 'read-only'", e);
-    }
-    if (parsedState == ProjectState.HIDDEN) {
-      throw error("state operator must be either 'active' or 'read-only'");
-    }
-    return ProjectPredicates.state(parsedState);
-  }
-
-  @Override
-  protected Predicate<ProjectData> defaultField(String query) throws QueryParseException {
-    // Adapt the capacity of this list when adding more default predicates.
-    List<Predicate<ProjectData>> preds = Lists.newArrayListWithCapacity(3);
-    preds.add(name(query));
-    preds.add(inname(query));
-    if (!Strings.isNullOrEmpty(query)) {
-      preds.add(description(query));
-    }
-    return Predicate.or(preds);
-  }
-
-  @Operator
-  public Predicate<ProjectData> limit(String query) throws QueryParseException {
-    Integer limit = Ints.tryParse(query);
-    if (limit == null) {
-      throw error("Invalid limit: " + query);
-    }
-    return new LimitPredicate<>(FIELD_LIMIT, limit);
-  }
+  /** See {@link com.google.gerrit.index.query.QueryBuilder#parse(String)}. */
+  Predicate<ProjectData> parse(String query) throws QueryParseException;
+  /** See {@link com.google.gerrit.index.query.QueryBuilder#parse(List<String>)}. */
+  List<Predicate<ProjectData>> parse(List<String> queries) throws QueryParseException;
 }
diff --git a/java/com/google/gerrit/server/query/project/ProjectQueryBuilderImpl.java b/java/com/google/gerrit/server/query/project/ProjectQueryBuilderImpl.java
new file mode 100644
index 0000000..f7135982
--- /dev/null
+++ b/java/com/google/gerrit/server/query/project/ProjectQueryBuilderImpl.java
@@ -0,0 +1,105 @@
+// Copyright (C) 2017 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.server.query.project;
+
+import com.google.common.base.Strings;
+import com.google.common.collect.Lists;
+import com.google.common.primitives.Ints;
+import com.google.gerrit.entities.Project;
+import com.google.gerrit.extensions.client.ProjectState;
+import com.google.gerrit.index.project.ProjectData;
+import com.google.gerrit.index.query.LimitPredicate;
+import com.google.gerrit.index.query.Predicate;
+import com.google.gerrit.index.query.QueryBuilder;
+import com.google.gerrit.index.query.QueryParseException;
+import com.google.inject.Inject;
+import java.util.List;
+
+/** Parses a query string meant to be applied to project objects. */
+public class ProjectQueryBuilderImpl extends QueryBuilder<ProjectData, ProjectQueryBuilderImpl>
+    implements ProjectQueryBuilder {
+  private static final QueryBuilder.Definition<ProjectData, ProjectQueryBuilderImpl> mydef =
+      new QueryBuilder.Definition<>(ProjectQueryBuilderImpl.class);
+
+  @Inject
+  ProjectQueryBuilderImpl() {
+    super(mydef, null);
+  }
+
+  @Operator
+  public Predicate<ProjectData> name(String name) {
+    return ProjectPredicates.name(Project.nameKey(name));
+  }
+
+  @Operator
+  public Predicate<ProjectData> parent(String parentName) {
+    return ProjectPredicates.parent(Project.nameKey(parentName));
+  }
+
+  @Operator
+  public Predicate<ProjectData> inname(String namePart) {
+    if (namePart.isEmpty()) {
+      return name(namePart);
+    }
+    return ProjectPredicates.inname(namePart);
+  }
+
+  @Operator
+  public Predicate<ProjectData> description(String description) throws QueryParseException {
+    if (Strings.isNullOrEmpty(description)) {
+      throw error("description operator requires a value");
+    }
+
+    return ProjectPredicates.description(description);
+  }
+
+  @Operator
+  public Predicate<ProjectData> state(String state) throws QueryParseException {
+    if (Strings.isNullOrEmpty(state)) {
+      throw error("state operator requires a value");
+    }
+    ProjectState parsedState;
+    try {
+      parsedState = ProjectState.valueOf(state.replace('-', '_').toUpperCase());
+    } catch (IllegalArgumentException e) {
+      throw error("state operator must be either 'active' or 'read-only'", e);
+    }
+    if (parsedState == ProjectState.HIDDEN) {
+      throw error("state operator must be either 'active' or 'read-only'");
+    }
+    return ProjectPredicates.state(parsedState);
+  }
+
+  @Override
+  protected Predicate<ProjectData> defaultField(String query) throws QueryParseException {
+    // Adapt the capacity of this list when adding more default predicates.
+    List<Predicate<ProjectData>> preds = Lists.newArrayListWithCapacity(3);
+    preds.add(name(query));
+    preds.add(inname(query));
+    if (!Strings.isNullOrEmpty(query)) {
+      preds.add(description(query));
+    }
+    return Predicate.or(preds);
+  }
+
+  @Operator
+  public Predicate<ProjectData> limit(String query) throws QueryParseException {
+    Integer limit = Ints.tryParse(query);
+    if (limit == null) {
+      throw error("Invalid limit: " + query);
+    }
+    return new LimitPredicate<>(FIELD_LIMIT, limit);
+  }
+}
diff --git a/java/com/google/gerrit/testing/InMemoryModule.java b/java/com/google/gerrit/testing/InMemoryModule.java
index aadf6d4..b828037 100644
--- a/java/com/google/gerrit/testing/InMemoryModule.java
+++ b/java/com/google/gerrit/testing/InMemoryModule.java
@@ -44,6 +44,7 @@
 import com.google.gerrit.server.account.GroupBackend;
 import com.google.gerrit.server.api.GerritApiModule;
 import com.google.gerrit.server.api.PluginApiModule;
+import com.google.gerrit.server.api.projects.ProjectQueryBuilderModule;
 import com.google.gerrit.server.audit.AuditModule;
 import com.google.gerrit.server.cache.h2.H2CacheModule;
 import com.google.gerrit.server.cache.mem.DefaultMemoryCacheModule;
@@ -191,6 +192,7 @@
     AuthConfig authConfig = cfgInjector.getInstance(AuthConfig.class);
     install(new AuthModule(authConfig));
     install(new GerritApiModule());
+    install(new ProjectQueryBuilderModule());
     factory(PluginUser.Factory.class);
     install(new PluginApiModule());
     install(new DefaultPermissionBackendModule());
diff --git a/javatests/com/google/gerrit/extensions/common/ChangeInfoDifferTest.java b/javatests/com/google/gerrit/extensions/common/ChangeInfoDifferTest.java
index 7ed236a..f45d33b 100644
--- a/javatests/com/google/gerrit/extensions/common/ChangeInfoDifferTest.java
+++ b/javatests/com/google/gerrit/extensions/common/ChangeInfoDifferTest.java
@@ -48,6 +48,7 @@
     assertThat(diff.added().messages).isNull();
     assertThat(diff.added().reviewers).isNull();
     assertThat(diff.added().hashtags).isNull();
+    assertThat(diff.added().removableLabels).isNull();
     assertThat(diff.removed()._number).isNull();
     assertThat(diff.removed().branch).isNull();
     assertThat(diff.removed().project).isNull();
@@ -56,6 +57,7 @@
     assertThat(diff.removed().messages).isNull();
     assertThat(diff.removed().reviewers).isNull();
     assertThat(diff.removed().hashtags).isNull();
+    assertThat(diff.removed().removableLabels).isNull();
   }
 
   @Test
@@ -315,6 +317,295 @@
   }
 
   @Test
+  public void getDiff_removableLabelsEmpty_returnsNullRemovableLabels() {
+    ChangeInfo oldChangeInfo = new ChangeInfo();
+    ChangeInfo newChangeInfo = new ChangeInfo();
+    oldChangeInfo.removableLabels = ImmutableMap.of();
+    newChangeInfo.removableLabels = ImmutableMap.of();
+
+    ChangeInfoDifference diff = ChangeInfoDiffer.getDifference(oldChangeInfo, newChangeInfo);
+
+    assertThat(diff.added().removableLabels).isNull();
+    assertThat(diff.removed().removableLabels).isNull();
+  }
+
+  @Test
+  public void getDiff_removableLabelsNullAndEmpty_returnsEmptyRemovableLabels() {
+    ChangeInfo oldChangeInfo = new ChangeInfo();
+    ChangeInfo newChangeInfo = new ChangeInfo();
+    newChangeInfo.removableLabels = ImmutableMap.of();
+
+    ChangeInfoDifference diff = ChangeInfoDiffer.getDifference(oldChangeInfo, newChangeInfo);
+
+    assertThat(diff.added().removableLabels).isEmpty();
+    assertThat(diff.removed().removableLabels).isNull();
+  }
+
+  @Test
+  public void getDiff_removableLabelsEmptyAndNull_returnsEmptyRemovableLabels() {
+    ChangeInfo oldChangeInfo = new ChangeInfo();
+    ChangeInfo newChangeInfo = new ChangeInfo();
+    oldChangeInfo.removableLabels = ImmutableMap.of();
+
+    ChangeInfoDifference diff = ChangeInfoDiffer.getDifference(oldChangeInfo, newChangeInfo);
+
+    assertThat(diff.added().removableLabels).isNull();
+    assertThat(diff.removed().removableLabels).isEmpty();
+  }
+
+  @Test
+  public void getDiff_removableLabelsLabelAdded() {
+    ChangeInfo oldChangeInfo = new ChangeInfo();
+    ChangeInfo newChangeInfo = new ChangeInfo();
+    AccountInfo acc1 = new AccountInfo();
+    acc1.name = "Cow";
+    AccountInfo acc2 = new AccountInfo();
+    acc2.name = "Pig";
+    AccountInfo acc3 = new AccountInfo();
+    acc3.name = "Cat";
+    AccountInfo acc4 = new AccountInfo();
+    acc4.name = "Dog";
+
+    oldChangeInfo.removableLabels =
+        ImmutableMap.of(
+            "Code-Review",
+            ImmutableMap.of("+1", ImmutableList.of(acc1), "-1", ImmutableList.of(acc2, acc3)));
+    newChangeInfo.removableLabels =
+        ImmutableMap.of(
+            "Code-Review",
+            ImmutableMap.of("+1", ImmutableList.of(acc1), "-1", ImmutableList.of(acc2, acc3)),
+            "Verified",
+            ImmutableMap.of("-1", ImmutableList.of(acc4)));
+
+    ChangeInfoDifference diff = ChangeInfoDiffer.getDifference(oldChangeInfo, newChangeInfo);
+
+    assertThat(diff.added().removableLabels)
+        .containsExactlyEntriesIn(
+            ImmutableMap.of("Verified", ImmutableMap.of("-1", ImmutableList.of(acc4))));
+    assertThat(diff.removed().removableLabels).isNull();
+  }
+
+  @Test
+  public void getDiff_removableLabelsLabelRemoved() {
+    ChangeInfo oldChangeInfo = new ChangeInfo();
+    ChangeInfo newChangeInfo = new ChangeInfo();
+    AccountInfo acc1 = new AccountInfo();
+    acc1.name = "Cow";
+    AccountInfo acc2 = new AccountInfo();
+    acc2.name = "Pig";
+    AccountInfo acc3 = new AccountInfo();
+    acc3.name = "Cat";
+    AccountInfo acc4 = new AccountInfo();
+    acc4.name = "Dog";
+
+    oldChangeInfo.removableLabels =
+        ImmutableMap.of(
+            "Code-Review",
+            ImmutableMap.of("+1", ImmutableList.of(acc1), "-1", ImmutableList.of(acc2, acc3)),
+            "Verified",
+            ImmutableMap.of("-1", ImmutableList.of(acc4)));
+    newChangeInfo.removableLabels =
+        ImmutableMap.of(
+            "Code-Review",
+            ImmutableMap.of("+1", ImmutableList.of(acc1), "-1", ImmutableList.of(acc2, acc3)));
+
+    ChangeInfoDifference diff = ChangeInfoDiffer.getDifference(oldChangeInfo, newChangeInfo);
+
+    assertThat(diff.added().removableLabels).isNull();
+    assertThat(diff.removed().removableLabels)
+        .containsExactlyEntriesIn(
+            ImmutableMap.of("Verified", ImmutableMap.of("-1", ImmutableList.of(acc4))));
+  }
+
+  @Test
+  public void getDiff_removableLabelsVoteAdded() {
+    ChangeInfo oldChangeInfo = new ChangeInfo();
+    ChangeInfo newChangeInfo = new ChangeInfo();
+    AccountInfo acc1 = new AccountInfo();
+    acc1.name = "acc1";
+    AccountInfo acc2 = new AccountInfo();
+    acc2.name = "acc2";
+    AccountInfo acc3 = new AccountInfo();
+    acc3.name = "acc3";
+
+    oldChangeInfo.removableLabels =
+        ImmutableMap.of("Code-Review", ImmutableMap.of("+1", ImmutableList.of(acc1)));
+    newChangeInfo.removableLabels =
+        ImmutableMap.of(
+            "Code-Review",
+            ImmutableMap.of("+1", ImmutableList.of(acc1), "-1", ImmutableList.of(acc2, acc3)));
+
+    ChangeInfoDifference diff = ChangeInfoDiffer.getDifference(oldChangeInfo, newChangeInfo);
+
+    assertThat(diff.added().removableLabels)
+        .containsExactlyEntriesIn(
+            ImmutableMap.of("Code-Review", ImmutableMap.of("-1", ImmutableList.of(acc2, acc3))));
+    assertThat(diff.removed().removableLabels).isNull();
+  }
+
+  @Test
+  public void getDiff_removableLabelsVoteRemoved() {
+    ChangeInfo oldChangeInfo = new ChangeInfo();
+    ChangeInfo newChangeInfo = new ChangeInfo();
+    AccountInfo acc1 = new AccountInfo();
+    acc1.name = "acc1";
+    AccountInfo acc2 = new AccountInfo();
+    acc2.name = "acc2";
+    AccountInfo acc3 = new AccountInfo();
+    acc3.name = "acc3";
+
+    oldChangeInfo.removableLabels =
+        ImmutableMap.of(
+            "Code-Review",
+            ImmutableMap.of("+1", ImmutableList.of(acc1), "-1", ImmutableList.of(acc2, acc3)));
+    newChangeInfo.removableLabels =
+        ImmutableMap.of("Code-Review", ImmutableMap.of("+1", ImmutableList.of(acc1)));
+
+    ChangeInfoDifference diff = ChangeInfoDiffer.getDifference(oldChangeInfo, newChangeInfo);
+
+    assertThat(diff.added().removableLabels).isNull();
+    assertThat(diff.removed().removableLabels)
+        .containsExactlyEntriesIn(
+            ImmutableMap.of("Code-Review", ImmutableMap.of("-1", ImmutableList.of(acc2, acc3))));
+  }
+
+  @Test
+  public void getDiff_removableLabelsAccountAdded() {
+    ChangeInfo oldChangeInfo = new ChangeInfo();
+    ChangeInfo newChangeInfo = new ChangeInfo();
+    AccountInfo acc1 = new AccountInfo();
+    acc1.name = "acc1";
+    AccountInfo acc2 = new AccountInfo();
+    acc2.name = "acc2";
+
+    oldChangeInfo.removableLabels =
+        ImmutableMap.of("Code-Review", ImmutableMap.of("+1", ImmutableList.of(acc1)));
+    newChangeInfo.removableLabels =
+        ImmutableMap.of("Code-Review", ImmutableMap.of("+1", ImmutableList.of(acc1, acc2)));
+
+    ChangeInfoDifference diff = ChangeInfoDiffer.getDifference(oldChangeInfo, newChangeInfo);
+
+    assertThat(diff.added().removableLabels)
+        .containsExactlyEntriesIn(
+            ImmutableMap.of("Code-Review", ImmutableMap.of("+1", ImmutableList.of(acc2))));
+    assertThat(diff.removed().removableLabels).isNull();
+  }
+
+  @Test
+  public void getDiff_removableLabelsAccountRemoved() {
+    ChangeInfo oldChangeInfo = new ChangeInfo();
+    ChangeInfo newChangeInfo = new ChangeInfo();
+    AccountInfo acc1 = new AccountInfo();
+    acc1.name = "acc1";
+    AccountInfo acc2 = new AccountInfo();
+    acc2.name = "acc2";
+
+    oldChangeInfo.removableLabels =
+        ImmutableMap.of("Code-Review", ImmutableMap.of("+1", ImmutableList.of(acc1)));
+    newChangeInfo.removableLabels =
+        ImmutableMap.of("Code-Review", ImmutableMap.of("+1", ImmutableList.of(acc1, acc2)));
+
+    ChangeInfoDifference diff = ChangeInfoDiffer.getDifference(oldChangeInfo, newChangeInfo);
+
+    assertThat(diff.added().removableLabels)
+        .containsExactlyEntriesIn(
+            ImmutableMap.of("Code-Review", ImmutableMap.of("+1", ImmutableList.of(acc2))));
+    assertThat(diff.removed().removableLabels).isNull();
+  }
+
+  @Test
+  public void getDiff_removableLabelsAccountChanged() {
+    ChangeInfo oldChangeInfo = new ChangeInfo();
+    ChangeInfo newChangeInfo = new ChangeInfo();
+    AccountInfo acc1 = new AccountInfo();
+    acc1.name = "acc1";
+    AccountInfo acc2 = new AccountInfo();
+    acc2.name = "acc2";
+
+    oldChangeInfo.removableLabels =
+        ImmutableMap.of("Code-Review", ImmutableMap.of("+1", ImmutableList.of(acc1)));
+    newChangeInfo.removableLabels =
+        ImmutableMap.of("Code-Review", ImmutableMap.of("+1", ImmutableList.of(acc2)));
+
+    ChangeInfoDifference diff = ChangeInfoDiffer.getDifference(oldChangeInfo, newChangeInfo);
+
+    assertThat(diff.added().removableLabels)
+        .containsExactlyEntriesIn(
+            ImmutableMap.of("Code-Review", ImmutableMap.of("+1", ImmutableList.of(acc2))));
+    assertThat(diff.removed().removableLabels)
+        .containsExactlyEntriesIn(
+            ImmutableMap.of("Code-Review", ImmutableMap.of("+1", ImmutableList.of(acc1))));
+  }
+
+  @Test
+  public void getDiff_removableLabelsScoreChanged() {
+    ChangeInfo oldChangeInfo = new ChangeInfo();
+    ChangeInfo newChangeInfo = new ChangeInfo();
+    AccountInfo acc1 = new AccountInfo();
+    acc1.name = "acc1";
+
+    oldChangeInfo.removableLabels =
+        ImmutableMap.of("Code-Review", ImmutableMap.of("+1", ImmutableList.of(acc1)));
+    newChangeInfo.removableLabels =
+        ImmutableMap.of("Code-Review", ImmutableMap.of("-1", ImmutableList.of(acc1)));
+
+    ChangeInfoDifference diff = ChangeInfoDiffer.getDifference(oldChangeInfo, newChangeInfo);
+
+    assertThat(diff.added().removableLabels)
+        .containsExactlyEntriesIn(
+            ImmutableMap.of("Code-Review", ImmutableMap.of("-1", ImmutableList.of(acc1))));
+    assertThat(diff.removed().removableLabels)
+        .containsExactlyEntriesIn(
+            ImmutableMap.of("Code-Review", ImmutableMap.of("+1", ImmutableList.of(acc1))));
+  }
+
+  @Test
+  public void getDiff_removableLabelsLabelChanged() {
+    ChangeInfo oldChangeInfo = new ChangeInfo();
+    ChangeInfo newChangeInfo = new ChangeInfo();
+    AccountInfo acc1 = new AccountInfo();
+    acc1.name = "acc1";
+
+    oldChangeInfo.removableLabels =
+        ImmutableMap.of("Code-Review", ImmutableMap.of("+1", ImmutableList.of(acc1)));
+    newChangeInfo.removableLabels =
+        ImmutableMap.of("Verified", ImmutableMap.of("+1", ImmutableList.of(acc1)));
+
+    ChangeInfoDifference diff = ChangeInfoDiffer.getDifference(oldChangeInfo, newChangeInfo);
+
+    assertThat(diff.added().removableLabels)
+        .containsExactlyEntriesIn(
+            ImmutableMap.of("Verified", ImmutableMap.of("+1", ImmutableList.of(acc1))));
+    assertThat(diff.removed().removableLabels)
+        .containsExactlyEntriesIn(
+            ImmutableMap.of("Code-Review", ImmutableMap.of("+1", ImmutableList.of(acc1))));
+  }
+
+  @Test
+  public void getDiff_removableLabelsLabelScoreAndAccountChanged() {
+    ChangeInfo oldChangeInfo = new ChangeInfo();
+    ChangeInfo newChangeInfo = new ChangeInfo();
+    AccountInfo acc1 = new AccountInfo();
+    acc1.name = "acc1";
+    AccountInfo acc2 = new AccountInfo();
+    acc2.name = "acc2";
+
+    oldChangeInfo.removableLabels =
+        ImmutableMap.of("Code-Review", ImmutableMap.of("+1", ImmutableList.of(acc1)));
+    newChangeInfo.removableLabels =
+        ImmutableMap.of("Verified", ImmutableMap.of("-1", ImmutableList.of(acc2)));
+
+    ChangeInfoDifference diff = ChangeInfoDiffer.getDifference(oldChangeInfo, newChangeInfo);
+
+    assertThat(diff.added().removableLabels)
+        .containsExactlyEntriesIn(
+            ImmutableMap.of("Verified", ImmutableMap.of("-1", ImmutableList.of(acc2))));
+    assertThat(diff.removed().removableLabels)
+        .containsExactlyEntriesIn(
+            ImmutableMap.of("Code-Review", ImmutableMap.of("+1", ImmutableList.of(acc1))));
+  }
+
+  @Test
   public void getDiff_assertCanConstructAllChangeInfoReferences() throws Exception {
     buildObjectWithFullFields(ChangeInfo.class);
   }
diff --git a/javatests/com/google/gerrit/server/query/change/AbstractQueryChangesTest.java b/javatests/com/google/gerrit/server/query/change/AbstractQueryChangesTest.java
index 8919e04..5d38c55 100644
--- a/javatests/com/google/gerrit/server/query/change/AbstractQueryChangesTest.java
+++ b/javatests/com/google/gerrit/server/query/change/AbstractQueryChangesTest.java
@@ -46,6 +46,7 @@
 import com.google.common.collect.Multimaps;
 import com.google.common.collect.Streams;
 import com.google.common.truth.ThrowableSubject;
+import com.google.errorprone.annotations.CanIgnoreReturnValue;
 import com.google.gerrit.acceptance.ExtensionRegistry;
 import com.google.gerrit.acceptance.ExtensionRegistry.Registration;
 import com.google.gerrit.acceptance.FakeSubmitRule;
@@ -109,12 +110,14 @@
 import com.google.gerrit.server.account.AuthRequest;
 import com.google.gerrit.server.account.ListGroupMembership;
 import com.google.gerrit.server.account.VersionedAccountQueries;
+import com.google.gerrit.server.account.externalids.ExternalId;
 import com.google.gerrit.server.account.externalids.ExternalIdFactory;
 import com.google.gerrit.server.change.ChangeInserter;
 import com.google.gerrit.server.change.ChangeTriplet;
 import com.google.gerrit.server.change.NotifyResolver;
 import com.google.gerrit.server.change.PatchSetInserter;
 import com.google.gerrit.server.config.AllUsersName;
+import com.google.gerrit.server.git.GitRepositoryManager;
 import com.google.gerrit.server.git.meta.MetaDataUpdate;
 import com.google.gerrit.server.group.testing.TestGroupBackend;
 import com.google.gerrit.server.index.change.ChangeField;
@@ -134,8 +137,6 @@
 import com.google.gerrit.server.util.ThreadLocalRequestContext;
 import com.google.gerrit.server.util.time.TimeUtil;
 import com.google.gerrit.testing.GerritServerTests;
-import com.google.gerrit.testing.InMemoryRepositoryManager;
-import com.google.gerrit.testing.InMemoryRepositoryManager.Repo;
 import com.google.gerrit.testing.TestChanges;
 import com.google.gerrit.testing.TestTimeUtil;
 import com.google.inject.Inject;
@@ -160,6 +161,7 @@
 import org.eclipse.jgit.lib.ObjectReader;
 import org.eclipse.jgit.lib.PersonIdent;
 import org.eclipse.jgit.lib.Ref;
+import org.eclipse.jgit.lib.Repository;
 import org.eclipse.jgit.revwalk.RevCommit;
 import org.eclipse.jgit.revwalk.RevWalk;
 import org.eclipse.jgit.util.SystemReader;
@@ -184,7 +186,7 @@
   @Inject protected ChangeIndexer indexer;
   @Inject protected ExtensionRegistry extensionRegistry;
   @Inject protected IndexConfig indexConfig;
-  @Inject protected InMemoryRepositoryManager repoManager;
+  @Inject protected GitRepositoryManager repoManager;
   @Inject protected Provider<AnonymousUser> anonymousUserProvider;
   @Inject protected Provider<InternalChangeQuery> queryProvider;
   @Inject protected ChangeNotes.Factory notesFactory;
@@ -207,11 +209,20 @@
 
   protected Injector injector;
   protected LifecycleManager lifecycle;
+
+  /**
+   * Index tests should not use username in query assert, since some backends do not use {@link
+   * ExternalId#SCHEME_USERNAME}
+   */
   protected Account.Id userId;
+
   protected CurrentUser user;
+  protected Account userAccount;
 
   private String systemTimeZone;
 
+  protected TestRepository<Repository> repo;
+
   protected abstract Injector createInjector();
 
   @Before
@@ -227,6 +238,10 @@
 
   @After
   public void cleanUp() {
+    if (repo != null) {
+      repo.close();
+      repo = null;
+    }
     lifecycle.stop();
   }
 
@@ -253,8 +268,9 @@
     return () -> requestUser;
   }
 
-  protected void resetUser() {
+  protected void resetUser() throws ConfigInvalidException, IOException {
     user = userFactory.create(userId);
+    userAccount = accounts.get(userId).get().account();
     requestContext.setContext(newRequestContext(userId));
   }
 
@@ -290,9 +306,9 @@
 
   @Test
   public void byId() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChange(repo));
-    Change change2 = insert(repo, newChange(repo));
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChange(repo));
+    Change change2 = insert("repo", newChange(repo));
 
     assertQuery("12345");
     assertQuery(change1.getId().get(), change1);
@@ -301,8 +317,8 @@
 
   @Test
   public void byKey() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change = insert(repo, newChange(repo));
+    repo = createAndOpenProject("repo");
+    Change change = insert("repo", newChange(repo));
     String key = change.getKey().get();
 
     assertQuery("I0000000000000000000000000000000000000000");
@@ -314,8 +330,8 @@
 
   @Test
   public void byTriplet() throws Exception {
-    TestRepository<Repo> repo = createProject("iabcde");
-    Change change = insert(repo, newChangeForBranch(repo, "branch"));
+    repo = createAndOpenProject("iabcde");
+    Change change = insert("iabcde", newChangeForBranch(repo, "branch"));
     String k = change.getKey().get();
 
     assertQuery("iabcde~branch~" + k, change);
@@ -337,11 +353,11 @@
 
   @Test
   public void byStatus() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     ChangeInserter ins1 = newChangeWithStatus(repo, Change.Status.NEW);
-    Change change1 = insert(repo, ins1);
+    Change change1 = insert("repo", ins1);
     ChangeInserter ins2 = newChangeWithStatus(repo, Change.Status.MERGED);
-    Change change2 = insert(repo, ins2);
+    Change change2 = insert("repo", ins2);
 
     assertQuery("status:new", change1);
     assertQuery("status:NEW", change1);
@@ -356,11 +372,11 @@
 
   @Test
   public void byStatusOr() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     ChangeInserter ins1 = newChangeWithStatus(repo, Change.Status.NEW);
-    Change change1 = insert(repo, ins1);
+    Change change1 = insert("repo", ins1);
     ChangeInserter ins2 = newChangeWithStatus(repo, Change.Status.MERGED);
-    Change change2 = insert(repo, ins2);
+    Change change2 = insert("repo", ins2);
 
     assertQuery("status:new OR status:merged", change2, change1);
     assertQuery("status:new or status:merged", change2, change1);
@@ -368,10 +384,10 @@
 
   @Test
   public void byStatusOpen() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     ChangeInserter ins1 = newChangeWithStatus(repo, Change.Status.NEW);
-    Change change1 = insert(repo, ins1);
-    insert(repo, newChangeWithStatus(repo, Change.Status.MERGED));
+    Change change1 = insert("repo", ins1);
+    insert("repo", newChangeWithStatus(repo, Change.Status.MERGED));
 
     Change[] expected = new Change[] {change1};
     assertQuery("status:open", expected);
@@ -390,12 +406,12 @@
 
   @Test
   public void byStatusClosed() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     ChangeInserter ins1 = newChangeWithStatus(repo, Change.Status.MERGED);
-    Change change1 = insert(repo, ins1);
+    Change change1 = insert("repo", ins1);
     ChangeInserter ins2 = newChangeWithStatus(repo, Change.Status.ABANDONED);
-    Change change2 = insert(repo, ins2);
-    insert(repo, newChangeWithStatus(repo, Change.Status.NEW));
+    Change change2 = insert("repo", ins2);
+    insert("repo", newChangeWithStatus(repo, Change.Status.NEW));
 
     Change[] expected = new Change[] {change2, change1};
     assertQuery("status:closed", expected);
@@ -411,12 +427,12 @@
 
   @Test
   public void byStatusAbandoned() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     ChangeInserter ins1 = newChangeWithStatus(repo, Change.Status.MERGED);
-    insert(repo, ins1);
+    insert("repo", ins1);
     ChangeInserter ins2 = newChangeWithStatus(repo, Change.Status.ABANDONED);
-    Change change1 = insert(repo, ins2);
-    insert(repo, newChangeWithStatus(repo, Change.Status.NEW));
+    Change change1 = insert("repo", ins2);
+    insert("repo", newChangeWithStatus(repo, Change.Status.NEW));
 
     assertQuery("status:abandoned", change1);
     assertQuery("status:ABANDONED", change1);
@@ -425,10 +441,10 @@
 
   @Test
   public void byStatusPrefix() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     ChangeInserter ins1 = newChangeWithStatus(repo, Change.Status.NEW);
-    Change change1 = insert(repo, ins1);
-    insert(repo, newChangeWithStatus(repo, Change.Status.MERGED));
+    Change change1 = insert("repo", ins1);
+    Change change2 = insert("repo", newChangeWithStatus(repo, Change.Status.MERGED));
 
     assertQuery("status:n", change1);
     assertQuery("status:ne", change1);
@@ -436,6 +452,7 @@
     assertQuery("status:N", change1);
     assertQuery("status:nE", change1);
     assertQuery("status:neW", change1);
+    assertQuery("status:m", change2);
     Exception thrown = assertThrows(BadRequestException.class, () -> assertQuery("status:newx"));
     assertThat(thrown).hasMessageThat().isEqualTo("Unrecognized value: newx");
     thrown = assertThrows(BadRequestException.class, () -> assertQuery("status:nx"));
@@ -444,11 +461,11 @@
 
   @Test
   public void byPrivate() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChange(repo), userId);
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChange(repo), userId);
     Account.Id user2 =
         accountManager.authenticate(authRequestFactory.createForUser("anotheruser")).getAccountId();
-    Change change2 = insert(repo, newChange(repo), user2);
+    Change change2 = insert("repo", newChange(repo), user2);
 
     // No private changes.
     assertQuery("is:open", change2, change1);
@@ -468,8 +485,8 @@
 
   @Test
   public void byWip() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChange(repo), userId);
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChange(repo), userId);
 
     assertQuery("is:open", change1);
     assertQuery("is:wip");
@@ -486,8 +503,8 @@
   @Test
   public void excludeWipChangeFromReviewersDashboards() throws Exception {
     Account.Id user1 = createAccount("user1");
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChangeWorkInProgress(repo), userId);
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChangeWorkInProgress(repo), userId);
 
     assertQuery("is:wip", change1);
     assertQuery("reviewer:" + user1);
@@ -503,8 +520,8 @@
 
   @Test
   public void byStarted() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChangeWorkInProgress(repo));
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChangeWorkInProgress(repo));
 
     assertQuery("is:started");
 
@@ -539,11 +556,11 @@
   @Test
   public void restorePendingReviewers() throws Exception {
     Project.NameKey project = Project.nameKey("repo");
-    TestRepository<Repo> repo = createProject(project.get());
+    repo = createAndOpenProject(project.get());
     ConfigInput conf = new ConfigInput();
     conf.enableReviewerByEmail = InheritableBoolean.TRUE;
     gApi.projects().name(project.get()).config(conf);
-    Change change1 = insert(repo, newChangeWorkInProgress(repo));
+    Change change1 = insert("repo", newChangeWorkInProgress(repo));
     Account.Id user1 = createAccount("user1");
     Account.Id user2 = createAccount("user2");
     String email1 = "email1@example.com";
@@ -596,9 +613,9 @@
 
   @Test
   public void byCommit() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     ChangeInserter ins = newChange(repo);
-    Change change = insert(repo, ins);
+    Change change = insert("repo", ins);
     String sha = ins.getCommitId().name();
 
     assertQuery("0000000000000000000000000000000000000000");
@@ -612,11 +629,11 @@
 
   @Test
   public void byOwner() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChange(repo), userId);
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChange(repo), userId);
     Account.Id user2 =
         accountManager.authenticate(authRequestFactory.createForUser("anotheruser")).getAccountId();
-    Change change2 = insert(repo, newChange(repo), user2);
+    Change change2 = insert("repo", newChange(repo), user2);
 
     assertQuery("is:owner", change1);
     assertQuery("owner:" + userId.get(), change1);
@@ -629,15 +646,16 @@
   @Test
   public void byUploader() throws Exception {
     assume().that(getSchema().hasField(ChangeField.UPLOADER_SPEC)).isTrue();
-    Account.Id user2 =
-        accountManager.authenticate(authRequestFactory.createForUser("anotheruser")).getAccountId();
-    CurrentUser user2CurrentUser = userFactory.create(user2);
 
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChange(repo), userId);
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChange(repo), userId);
     assertQuery("is:uploader", change1);
     assertQuery("uploader:" + userId.get(), change1);
-    change1 = newPatchSet(repo, change1, user2CurrentUser, /* message= */ Optional.empty());
+
+    Account.Id user2 = createAccount("anotheruser");
+    CurrentUser user2CurrentUser = userFactory.create(user2);
+
+    change1 = newPatchSet("repo", change1, user2CurrentUser, /* message= */ Optional.empty());
     // Uploader has changed
     assertQuery("uploader:" + userId.get());
     assertQuery("uploader:" + user2.get(), change1);
@@ -670,7 +688,7 @@
   }
 
   private void byAuthorOrCommitterExact(String searchOperator) throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    createProject("repo");
     PersonIdent johnDoe = new PersonIdent("John Doe", "john.doe@example.com");
     PersonIdent john = new PersonIdent("John", "john@example.com");
     PersonIdent doeSmith = new PersonIdent("Doe Smith", "doe_smith@example.com");
@@ -678,10 +696,10 @@
     PersonIdent myself = new PersonIdent("I Am", ua.preferredEmail());
     PersonIdent selfName = new PersonIdent("My Self", "my.self@example.com");
 
-    Change change1 = createChange(repo, johnDoe);
-    Change change2 = createChange(repo, john);
-    Change change3 = createChange(repo, doeSmith);
-    createChange(repo, selfName);
+    Change change1 = createChange("repo", johnDoe);
+    Change change2 = createChange("repo", john);
+    Change change3 = createChange("repo", doeSmith);
+    createChange("repo", selfName);
 
     // Only email address.
     assertQuery(searchOperator + "john.doe@example.com", change1);
@@ -706,19 +724,19 @@
     assertQuery(searchOperator + "self");
 
     // ':self' matches a change created with the current user's email address
-    Change change5 = createChange(repo, myself);
+    Change change5 = createChange("repo", myself);
     assertQuery(searchOperator + "me", change5);
     assertQuery(searchOperator + "self", change5);
   }
 
   private void byAuthorOrCommitterFullText(String searchOperator) throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    createProject("repo");
     PersonIdent johnDoe = new PersonIdent("John Doe", "john.doe@example.com");
     PersonIdent john = new PersonIdent("John", "john@example.com");
     PersonIdent doeSmith = new PersonIdent("Doe Smith", "doe_smith@example.com");
-    Change change1 = createChange(repo, johnDoe);
-    Change change2 = createChange(repo, john);
-    Change change3 = createChange(repo, doeSmith);
+    Change change1 = createChange("repo", johnDoe);
+    Change change2 = createChange("repo", john);
+    Change change3 = createChange("repo", doeSmith);
 
     // By exact name.
     assertQuery(searchOperator + "\"John Doe\"", change1);
@@ -739,20 +757,25 @@
     assertThat(thrown).hasMessageThat().contains("invalid value");
   }
 
-  protected Change createChange(TestRepository<Repo> repo, PersonIdent person) throws Exception {
-    RevCommit commit =
-        repo.parseBody(repo.commit().message("message").author(person).committer(person).create());
-    return insert(repo, newChangeForCommit(repo, commit), null);
+  @CanIgnoreReturnValue
+  protected Change createChange(String repoName, PersonIdent person) throws Exception {
+    try (TestRepository<Repository> repo =
+        new TestRepository<>(repoManager.openRepository(Project.nameKey(repoName)))) {
+      RevCommit commit =
+          repo.parseBody(
+              repo.commit().message("message").author(person).committer(person).create());
+      return insert("repo", newChangeForCommit(repo, commit), null);
+    }
   }
 
   @Test
   public void byOwnerIn() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChange(repo), userId);
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChange(repo), userId);
     Account.Id user2 =
         accountManager.authenticate(authRequestFactory.createForUser("anotheruser")).getAccountId();
-    Change change2 = insert(repo, newChange(repo), user2);
-    Change change3 = insert(repo, newChange(repo), user2);
+    Change change2 = insert("repo", newChange(repo), user2);
+    Change change3 = insert("repo", newChange(repo), user2);
     gApi.changes().id(change3.getId().get()).current().review(ReviewInput.approve());
     gApi.changes().id(change3.getId().get()).current().submit();
 
@@ -765,24 +788,25 @@
   @Test
   public void byUploaderIn() throws Exception {
     assume().that(getSchema().hasField(ChangeField.UPLOADER_SPEC)).isTrue();
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChange(repo), userId);
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChange(repo), userId);
+
     assertQuery("uploaderin:Administrators", change1);
 
-    Account.Id user2 =
-        accountManager.authenticate(authRequestFactory.createForUser("anotheruser")).getAccountId();
+    Account.Id user2 = createAccount("anotheruser");
     CurrentUser user2CurrentUser = userFactory.create(user2);
-    change1 = newPatchSet(repo, change1, user2CurrentUser, /* message= */ Optional.empty());
+    change1 = newPatchSet("repo", change1, user2CurrentUser, /* message= */ Optional.empty());
+
     assertQuery("uploaderin:Administrators");
     assertQuery("uploaderin:\"Registered Users\"", change1);
   }
 
   @Test
   public void byProject() throws Exception {
-    TestRepository<Repo> repo1 = createProject("repo1");
-    TestRepository<Repo> repo2 = createProject("repo2");
-    Change change1 = insert(repo1, newChange(repo1));
-    Change change2 = insert(repo2, newChange(repo2));
+    createProject("repo1");
+    createProject("repo2");
+    Change change1 = insert("repo1", newChange("repo1"));
+    Change change2 = insert("repo2", newChange("repo2"));
 
     assertQuery("project:foo");
     assertQuery("project:repo");
@@ -792,16 +816,16 @@
 
   @Test
   public void byProjectWithHidden() throws Exception {
-    TestRepository<Repo> hiddenProject = createProject("hiddenProject");
-    insert(hiddenProject, newChange(hiddenProject));
+    createProject("hiddenProject");
+    insert("hiddenProject", newChange("hiddenProject"));
     projectOperations
         .project(Project.nameKey("hiddenProject"))
         .forUpdate()
         .add(block(Permission.READ).ref("refs/*").group(REGISTERED_USERS))
         .update();
 
-    TestRepository<Repo> visibleProject = createProject("visibleProject");
-    Change visibleChange = insert(visibleProject, newChange(visibleProject));
+    createProject("visibleProject");
+    Change visibleChange = insert("visibleProject", newChange("visibleProject"));
     assertQuery("project:visibleProject", visibleChange);
     assertQuery("project:hiddenProject");
     assertQuery("project:visibleProject OR project:hiddenProject", visibleChange);
@@ -809,13 +833,13 @@
 
   @Test
   public void byParentOf() throws Exception {
-    TestRepository<Repo> repo1 = createProject("repo1");
-    RevCommit commit1 = repo1.parseBody(repo1.commit().message("message").create());
-    Change change1 = insert(repo1, newChangeForCommit(repo1, commit1));
-    RevCommit commit2 = repo1.parseBody(repo1.commit(commit1));
-    Change change2 = insert(repo1, newChangeForCommit(repo1, commit2));
-    RevCommit commit3 = repo1.parseBody(repo1.commit(commit1, commit2));
-    Change change3 = insert(repo1, newChangeForCommit(repo1, commit3));
+    repo = createAndOpenProject("repo1");
+    RevCommit commit1 = repo.parseBody(repo.commit().message("message").create());
+    Change change1 = insert("repo1", newChangeForCommit(repo, commit1));
+    RevCommit commit2 = repo.parseBody(repo.commit(commit1));
+    Change change2 = insert("repo1", newChangeForCommit(repo, commit2));
+    RevCommit commit3 = repo.parseBody(repo.commit(commit1, commit2));
+    Change change3 = insert("repo1", newChangeForCommit(repo, commit3));
 
     assertQuery("parentof:" + change1.getId().get());
     assertQuery("parentof:" + change1.getKey().get());
@@ -827,10 +851,10 @@
 
   @Test
   public void byParentProject() throws Exception {
-    TestRepository<Repo> repo1 = createProject("repo1");
-    TestRepository<Repo> repo2 = createProject("repo2", "repo1");
-    Change change1 = insert(repo1, newChange(repo1));
-    Change change2 = insert(repo2, newChange(repo2));
+    createProject("repo1");
+    createProject("repo2", "repo1");
+    Change change1 = insert("repo1", newChange("repo1"));
+    Change change2 = insert("repo2", newChange("repo2"));
 
     assertQuery("parentproject:repo1", change2, change1);
     assertQuery("parentproject:repo2", change2);
@@ -838,10 +862,10 @@
 
   @Test
   public void byProjectPrefix() throws Exception {
-    TestRepository<Repo> repo1 = createProject("repo1");
-    TestRepository<Repo> repo2 = createProject("repo2");
-    Change change1 = insert(repo1, newChange(repo1));
-    Change change2 = insert(repo2, newChange(repo2));
+    createProject("repo1");
+    createProject("repo2");
+    Change change1 = insert("repo1", newChange("repo1"));
+    Change change2 = insert("repo2", newChange("repo2"));
 
     assertQuery("projects:foo");
     assertQuery("projects:repo1", change1);
@@ -851,10 +875,10 @@
 
   @Test
   public void byRepository() throws Exception {
-    TestRepository<Repo> repo1 = createProject("repo1");
-    TestRepository<Repo> repo2 = createProject("repo2");
-    Change change1 = insert(repo1, newChange(repo1));
-    Change change2 = insert(repo2, newChange(repo2));
+    createProject("repo1");
+    createProject("repo2");
+    Change change1 = insert("repo1", newChange("repo1"));
+    Change change2 = insert("repo2", newChange("repo2"));
 
     assertQuery("repository:foo");
     assertQuery("repository:repo");
@@ -864,10 +888,10 @@
 
   @Test
   public void byParentRepository() throws Exception {
-    TestRepository<Repo> repo1 = createProject("repo1");
-    TestRepository<Repo> repo2 = createProject("repo2", "repo1");
-    Change change1 = insert(repo1, newChange(repo1));
-    Change change2 = insert(repo2, newChange(repo2));
+    createProject("repo1");
+    createProject("repo2", "repo1");
+    Change change1 = insert("repo1", newChange("repo1"));
+    Change change2 = insert("repo2", newChange("repo2"));
 
     assertQuery("parentrepository:repo1", change2, change1);
     assertQuery("parentrepository:repo2", change2);
@@ -875,10 +899,10 @@
 
   @Test
   public void byRepositoryPrefix() throws Exception {
-    TestRepository<Repo> repo1 = createProject("repo1");
-    TestRepository<Repo> repo2 = createProject("repo2");
-    Change change1 = insert(repo1, newChange(repo1));
-    Change change2 = insert(repo2, newChange(repo2));
+    createProject("repo1");
+    createProject("repo2");
+    Change change1 = insert("repo1", newChange("repo1"));
+    Change change2 = insert("repo2", newChange("repo2"));
 
     assertQuery("repositories:foo");
     assertQuery("repositories:repo1", change1);
@@ -888,10 +912,10 @@
 
   @Test
   public void byRepo() throws Exception {
-    TestRepository<Repo> repo1 = createProject("repo1");
-    TestRepository<Repo> repo2 = createProject("repo2");
-    Change change1 = insert(repo1, newChange(repo1));
-    Change change2 = insert(repo2, newChange(repo2));
+    createProject("repo1");
+    createProject("repo2");
+    Change change1 = insert("repo1", newChange("repo1"));
+    Change change2 = insert("repo2", newChange("repo2"));
 
     assertQuery("repo:foo");
     assertQuery("repo:repo");
@@ -901,10 +925,10 @@
 
   @Test
   public void byParentRepo() throws Exception {
-    TestRepository<Repo> repo1 = createProject("repo1");
-    TestRepository<Repo> repo2 = createProject("repo2", "repo1");
-    Change change1 = insert(repo1, newChange(repo1));
-    Change change2 = insert(repo2, newChange(repo2));
+    createProject("repo1");
+    createProject("repo2", "repo1");
+    Change change1 = insert("repo1", newChange("repo1"));
+    Change change2 = insert("repo2", newChange("repo2"));
 
     assertQuery("parentrepo:repo1", change2, change1);
     assertQuery("parentrepo:repo2", change2);
@@ -912,10 +936,10 @@
 
   @Test
   public void byRepoPrefix() throws Exception {
-    TestRepository<Repo> repo1 = createProject("repo1");
-    TestRepository<Repo> repo2 = createProject("repo2");
-    Change change1 = insert(repo1, newChange(repo1));
-    Change change2 = insert(repo2, newChange(repo2));
+    createProject("repo1");
+    createProject("repo2");
+    Change change1 = insert("repo1", newChange("repo1"));
+    Change change2 = insert("repo2", newChange("repo2"));
 
     assertQuery("repos:foo");
     assertQuery("repos:repo1", change1);
@@ -925,9 +949,9 @@
 
   @Test
   public void byBranchAndRef() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChangeForBranch(repo, "master"));
-    Change change2 = insert(repo, newChangeForBranch(repo, "branch"));
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChangeForBranch(repo, "master"));
+    Change change2 = insert("repo", newChangeForBranch(repo, "branch"));
 
     assertQuery("branch:foo");
     assertQuery("branch:master", change1);
@@ -944,26 +968,26 @@
   @Test
   public void byTopic() throws Exception {
 
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     ChangeInserter ins1 = newChangeWithTopic(repo, "feature1");
-    Change change1 = insert(repo, ins1);
+    Change change1 = insert("repo", ins1);
 
     ChangeInserter ins2 = newChangeWithTopic(repo, "feature2");
-    Change change2 = insert(repo, ins2);
+    Change change2 = insert("repo", ins2);
 
     ChangeInserter ins3 = newChangeWithTopic(repo, "Cherrypick-feature2");
-    Change change3 = insert(repo, ins3);
+    Change change3 = insert("repo", ins3);
 
     ChangeInserter ins4 = newChangeWithTopic(repo, "feature2-fixup");
-    Change change4 = insert(repo, ins4);
+    Change change4 = insert("repo", ins4);
 
     ChangeInserter ins5 = newChangeWithTopic(repo, "https://gerrit.local");
-    Change change5 = insert(repo, ins5);
+    Change change5 = insert("repo", ins5);
 
     ChangeInserter ins6 = newChangeWithTopic(repo, "git_gerrit_training");
-    Change change6 = insert(repo, ins6);
+    Change change6 = insert("repo", ins6);
 
-    Change change_no_topic = insert(repo, newChange(repo));
+    Change changeNoTopic = insert("repo", newChange(repo));
 
     assertQuery("intopic:foo");
     assertQuery("intopic:feature1", change1);
@@ -972,8 +996,8 @@
     assertQuery("intopic:feature2", change4, change3, change2);
     assertQuery("intopic:fixup", change4);
     assertQuery("intopic:gerrit", change6, change5);
-    assertQuery("topic:\"\"", change_no_topic);
-    assertQuery("intopic:\"\"", change_no_topic);
+    assertQuery("topic:\"\"", changeNoTopic);
+    assertQuery("intopic:\"\"", changeNoTopic);
 
     assume().that(getSchema().hasField(ChangeField.PREFIX_TOPIC)).isTrue();
     assertQuery("prefixtopic:feature", change4, change2, change1);
@@ -983,16 +1007,16 @@
 
   @Test
   public void byTopicRegex() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
 
     ChangeInserter ins1 = newChangeWithTopic(repo, "feature1");
-    Change change1 = insert(repo, ins1);
+    Change change1 = insert("repo", ins1);
 
     ChangeInserter ins2 = newChangeWithTopic(repo, "Cherrypick-feature1");
-    Change change2 = insert(repo, ins2);
+    Change change2 = insert("repo", ins2);
 
     ChangeInserter ins3 = newChangeWithTopic(repo, "feature1-fixup");
-    Change change3 = insert(repo, ins3);
+    Change change3 = insert("repo", ins3);
 
     assertQuery("intopic:^feature1.*", change3, change1);
     assertQuery("intopic:{^.*feature1$}", change2, change1);
@@ -1000,13 +1024,13 @@
 
   @Test
   public void byMessageExact() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     RevCommit commit1 = repo.parseBody(repo.commit().message("one").create());
-    Change change1 = insert(repo, newChangeForCommit(repo, commit1));
+    Change change1 = insert("repo", newChangeForCommit(repo, commit1));
     RevCommit commit2 = repo.parseBody(repo.commit().message("two").create());
-    Change change2 = insert(repo, newChangeForCommit(repo, commit2));
+    Change change2 = insert("repo", newChangeForCommit(repo, commit2));
     RevCommit commit3 = repo.parseBody(repo.commit().message("A great \"fix\" to my bug").create());
-    Change change3 = insert(repo, newChangeForCommit(repo, commit3));
+    Change change3 = insert("repo", newChangeForCommit(repo, commit3));
 
     assertQuery("message:foo");
     assertQuery("message:one", change1);
@@ -1017,16 +1041,16 @@
   @Test
   public void byMessageRegEx() throws Exception {
     assume().that(getSchema().hasField(ChangeField.COMMIT_MESSAGE_EXACT)).isTrue();
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     RevCommit commit1 = repo.parseBody(repo.commit().message("aaaabcc").create());
-    Change change1 = insert(repo, newChangeForCommit(repo, commit1));
+    Change change1 = insert("repo", newChangeForCommit(repo, commit1));
     RevCommit commit2 = repo.parseBody(repo.commit().message("aaaacc").create());
-    Change change2 = insert(repo, newChangeForCommit(repo, commit2));
+    Change change2 = insert("repo", newChangeForCommit(repo, commit2));
     RevCommit commit3 = repo.parseBody(repo.commit().message("Title\n\nHELLO WORLD").create());
-    Change change3 = insert(repo, newChangeForCommit(repo, commit3));
+    Change change3 = insert("repo", newChangeForCommit(repo, commit3));
     RevCommit commit4 =
         repo.parseBody(repo.commit().message("Title\n\nfoobar hello WORLD").create());
-    Change change4 = insert(repo, newChangeForCommit(repo, commit4));
+    Change change4 = insert("repo", newChangeForCommit(repo, commit4));
 
     assertQuery("message:\"^aaaa(b|c)*\"", change2, change1);
     assertQuery("message:\"^aaaa(c)*c.*\"", change2);
@@ -1038,7 +1062,7 @@
   @Test
   public void bySubject() throws Exception {
     assume().that(getSchema().hasField(ChangeField.SUBJECT_SPEC)).isTrue();
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     RevCommit commit1 =
         repo.parseBody(
             repo.commit()
@@ -1047,7 +1071,7 @@
                         + "Message body\n\n"
                         + "Change-Id: I986c6a013dd5b3a2e8a0271c04deac2c9752b920")
                 .create());
-    Change change1 = insert(repo, newChangeForCommit(repo, commit1));
+    Change change1 = insert("repo", newChangeForCommit(repo, commit1));
     RevCommit commit2 =
         repo.parseBody(
             repo.commit()
@@ -1056,7 +1080,7 @@
                         + "Message body for another commit\n\n"
                         + "Change-Id: I986c6a013dd5b3a2e8a0271c04deac2c9752b921")
                 .create());
-    Change change2 = insert(repo, newChangeForCommit(repo, commit2));
+    Change change2 = insert("repo", newChangeForCommit(repo, commit2));
     RevCommit commit3 =
         repo.parseBody(
             repo.commit()
@@ -1065,7 +1089,7 @@
                         + "Last message body\n\n"
                         + "Change-Id: I986c6a013dd5b3a2e8a0271c04deac2c9752b921")
                 .create());
-    Change change3 = insert(repo, newChangeForCommit(repo, commit3));
+    Change change3 = insert("repo", newChangeForCommit(repo, commit3));
 
     assertQuery("subject:First", change1);
     assertQuery("subject:Second", change2);
@@ -1075,7 +1099,7 @@
     assertQuery("subject:body");
     change1 =
         newPatchSet(
-            repo,
+            "repo",
             change1,
             user,
             Optional.of("Rework of commit with test subject\n\n" + "Message body\n\n"));
@@ -1087,7 +1111,7 @@
   @Test
   public void bySubjectPrefix() throws Exception {
     assume().that(getSchema().hasField(ChangeField.PREFIX_SUBJECT_SPEC)).isTrue();
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     RevCommit commit1 =
         repo.parseBody(
             repo.commit()
@@ -1096,7 +1120,7 @@
                         + "Message body\n\n"
                         + "Change-Id: I986c6a013dd5b3a2e8a0271c04deac2c9752b920")
                 .create());
-    Change change1 = insert(repo, newChangeForCommit(repo, commit1));
+    Change change1 = insert("repo", newChangeForCommit(repo, commit1));
     RevCommit commit2 =
         repo.parseBody(
             repo.commit()
@@ -1105,7 +1129,7 @@
                         + "Message body for another commit\n\n"
                         + "Change-Id: I986c6a013dd5b3a2e8a0271c04deac2c9752b921")
                 .create());
-    Change change2 = insert(repo, newChangeForCommit(repo, commit2));
+    Change change2 = insert("repo", newChangeForCommit(repo, commit2));
     RevCommit commit3 =
         repo.parseBody(
             repo.commit()
@@ -1114,7 +1138,7 @@
                         + "Last message body\n\n"
                         + "Change-Id: I986c6a013dd5b3a2e8a0271c04deac2c9752b921")
                 .create());
-    Change change3 = insert(repo, newChangeForCommit(repo, commit3));
+    Change change3 = insert("repo", newChangeForCommit(repo, commit3));
 
     assertQuery("prefixsubject:\"[FOO\"", change3, change1);
     assertQuery("prefixsubject:\"[BAR\"", change2);
@@ -1124,7 +1148,7 @@
     assertQuery("prefixsubject:FOO");
     change1 =
         newPatchSet(
-            repo,
+            "repo",
             change1,
             user,
             Optional.of("[BAR123] Rework of commit with test subject\n\n" + "Message body\n\n"));
@@ -1134,11 +1158,11 @@
 
   @Test
   public void fullTextWithNumbers() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     RevCommit commit1 = repo.parseBody(repo.commit().message("12345 67890").create());
-    Change change1 = insert(repo, newChangeForCommit(repo, commit1));
+    Change change1 = insert("repo", newChangeForCommit(repo, commit1));
     RevCommit commit2 = repo.parseBody(repo.commit().message("12346 67891").create());
-    Change change2 = insert(repo, newChangeForCommit(repo, commit2));
+    Change change2 = insert("repo", newChangeForCommit(repo, commit2));
 
     assertQuery("message:1234");
     assertQuery("message:12345", change1);
@@ -1147,13 +1171,13 @@
 
   @Test
   public void fullTextMultipleTerms() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     RevCommit commit1 = repo.parseBody(repo.commit().message("Signed-off: owner").create());
-    Change change1 = insert(repo, newChangeForCommit(repo, commit1));
+    Change change1 = insert("repo", newChangeForCommit(repo, commit1));
     RevCommit commit2 = repo.parseBody(repo.commit().message("Signed by owner").create());
-    Change change2 = insert(repo, newChangeForCommit(repo, commit2));
+    Change change2 = insert("repo", newChangeForCommit(repo, commit2));
     RevCommit commit3 = repo.parseBody(repo.commit().message("This change is off").create());
-    Change change3 = insert(repo, newChangeForCommit(repo, commit3));
+    Change change3 = insert("repo", newChangeForCommit(repo, commit3));
 
     assertQuery("message:\"Signed-off: owner\"", change1);
     assertQuery("message:\"Signed\"", change2, change1);
@@ -1162,11 +1186,11 @@
 
   @Test
   public void byMessageMixedCase() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     RevCommit commit1 = repo.parseBody(repo.commit().message("Hello gerrit").create());
-    Change change1 = insert(repo, newChangeForCommit(repo, commit1));
+    Change change1 = insert("repo", newChangeForCommit(repo, commit1));
     RevCommit commit2 = repo.parseBody(repo.commit().message("Hello Gerrit").create());
-    Change change2 = insert(repo, newChangeForCommit(repo, commit2));
+    Change change2 = insert("repo", newChangeForCommit(repo, commit2));
 
     assertQuery("message:gerrit", change2, change1);
     assertQuery("message:Gerrit", change2, change1);
@@ -1174,16 +1198,16 @@
 
   @Test
   public void byMessageSubstring() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     RevCommit commit1 = repo.parseBody(repo.commit().message("https://gerrit.local").create());
-    Change change1 = insert(repo, newChangeForCommit(repo, commit1));
+    Change change1 = insert("repo", newChangeForCommit(repo, commit1));
     assertQuery("message:gerrit", change1);
   }
 
   @Test
   public void byLabel() throws Exception {
-    accountManager.authenticate(authRequestFactory.createForUser("anotheruser"));
-    TestRepository<Repo> repo = createProject("repo");
+    Account.Id anotherUser = createAccount("anotheruser");
+    repo = createAndOpenProject("repo");
     ChangeInserter ins = newChange(repo);
     ChangeInserter ins2 = newChange(repo);
     ChangeInserter ins3 = newChange(repo);
@@ -1191,24 +1215,24 @@
     ChangeInserter ins5 = newChange(repo);
     ChangeInserter ins6 = newChange(repo);
 
-    Change reviewMinus2Change = insert(repo, ins);
+    Change reviewMinus2Change = insert("repo", ins);
     gApi.changes().id(reviewMinus2Change.getId().get()).current().review(ReviewInput.reject());
 
-    Change reviewMinus1Change = insert(repo, ins2);
+    Change reviewMinus1Change = insert("repo", ins2);
     gApi.changes().id(reviewMinus1Change.getId().get()).current().review(ReviewInput.dislike());
 
-    Change noLabelChange = insert(repo, ins3);
+    Change noLabelChange = insert("repo", ins3);
 
-    Change reviewPlus1Change = insert(repo, ins4);
+    Change reviewPlus1Change = insert("repo", ins4);
     gApi.changes().id(reviewPlus1Change.getId().get()).current().review(ReviewInput.recommend());
 
-    Change reviewTwoPlus1Change = insert(repo, ins5);
+    Change reviewTwoPlus1Change = insert("repo", ins5);
     gApi.changes().id(reviewTwoPlus1Change.getId().get()).current().review(ReviewInput.recommend());
     requestContext.setContext(newRequestContext(createAccount("user1")));
     gApi.changes().id(reviewTwoPlus1Change.getId().get()).current().review(ReviewInput.recommend());
     requestContext.setContext(newRequestContext(userId));
 
-    Change reviewPlus2Change = insert(repo, ins6);
+    Change reviewPlus2Change = insert("repo", ins6);
     gApi.changes().id(reviewPlus2Change.getId().get()).current().review(ReviewInput.approve());
 
     Map<String, Short> m =
@@ -1272,9 +1296,15 @@
     assertQuery("label:Code-Review<=-2", reviewMinus2Change);
     assertQuery("label:Code-Review<-2");
 
-    assertQuery("label:Code-Review=+1,anotheruser");
-    assertQuery("label:Code-Review=+1,user", reviewTwoPlus1Change, reviewPlus1Change);
-    assertQuery("label:Code-Review=+1,user=user", reviewTwoPlus1Change, reviewPlus1Change);
+    assertQuery("label:Code-Review=+1," + anotherUser);
+    assertQuery(
+        String.format("label:Code-Review=+1,%s", userAccount.preferredEmail()),
+        reviewTwoPlus1Change,
+        reviewPlus1Change);
+    assertQuery(
+        String.format("label:Code-Review=+1,user=%s", userAccount.preferredEmail()),
+        reviewTwoPlus1Change,
+        reviewPlus1Change);
     assertQuery("label:Code-Review=+1,Administrators", reviewTwoPlus1Change, reviewPlus1Change);
     assertQuery(
         "label:Code-Review=+1,group=Administrators", reviewTwoPlus1Change, reviewPlus1Change);
@@ -1341,9 +1371,8 @@
 
   @Test
   public void byLabelMulti() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Project.NameKey project =
-        Project.nameKey(repo.getRepository().getDescription().getRepositoryName());
+    Project.NameKey project = Project.nameKey("repo");
+    repo = createAndOpenProject(project.get());
 
     LabelType verified =
         label(LabelId.VERIFIED, value(1, "Passes"), value(0, "No score"), value(-1, "Failed"));
@@ -1370,25 +1399,25 @@
     ChangeInserter ins5 = newChange(repo);
 
     // CR+1
-    Change reviewCRplus1 = insert(repo, ins);
+    Change reviewCRplus1 = insert(project.get(), ins);
     gApi.changes().id(reviewCRplus1.getId().get()).current().review(ReviewInput.recommend());
 
     // CR+2
-    Change reviewCRplus2 = insert(repo, ins2);
+    Change reviewCRplus2 = insert(project.get(), ins2);
     gApi.changes().id(reviewCRplus2.getId().get()).current().review(ReviewInput.approve());
 
     // CR+1 VR+1
-    Change reviewCRplus1VRplus1 = insert(repo, ins3);
+    Change reviewCRplus1VRplus1 = insert(project.get(), ins3);
     gApi.changes().id(reviewCRplus1VRplus1.getId().get()).current().review(ReviewInput.recommend());
     gApi.changes().id(reviewCRplus1VRplus1.getId().get()).current().review(reviewVerified);
 
     // CR+2 VR+1
-    Change reviewCRplus2VRplus1 = insert(repo, ins4);
+    Change reviewCRplus2VRplus1 = insert(project.get(), ins4);
     gApi.changes().id(reviewCRplus2VRplus1.getId().get()).current().review(ReviewInput.approve());
     gApi.changes().id(reviewCRplus2VRplus1.getId().get()).current().review(reviewVerified);
 
     // VR+1
-    Change reviewVRplus1 = insert(repo, ins5);
+    Change reviewVRplus1 = insert(project.get(), ins5);
     gApi.changes().id(reviewVRplus1.getId().get()).current().review(reviewVerified);
 
     assertQuery("label:Code-Review=+1", reviewCRplus1VRplus1, reviewCRplus1);
@@ -1407,28 +1436,28 @@
 
   @Test
   public void byLabelNotOwner() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     ChangeInserter ins = newChange(repo);
     Account.Id user1 = createAccount("user1");
 
-    Change reviewPlus1Change = insert(repo, ins);
+    Change reviewPlus1Change = insert("repo", ins);
 
     // post a review with user1
     requestContext.setContext(newRequestContext(user1));
     gApi.changes().id(reviewPlus1Change.getId().get()).current().review(ReviewInput.recommend());
 
-    assertQuery("label:Code-Review=+1,user=user1", reviewPlus1Change);
+    assertQuery("label:Code-Review=+1,user=" + user1, reviewPlus1Change);
     assertQuery("label:Code-Review=+1,owner");
   }
 
   @Test
   public void byLabelNonUploader() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     ChangeInserter ins = newChange(repo);
     Account.Id user1 = createAccount("user1");
 
     // create a change with "user"
-    Change reviewPlus1Change = insert(repo, ins);
+    Change reviewPlus1Change = insert("repo", ins);
 
     // add a +1 vote with "user". Query doesn't match since voter is the uploader.
     gApi.changes().id(reviewPlus1Change.getId().get()).current().review(ReviewInput.recommend());
@@ -1467,8 +1496,8 @@
   @Test
   public void byLabelGroup() throws Exception {
     Account.Id user1 = createAccount("user1");
-    createAccount("user2");
-    TestRepository<Repo> repo = createProject("repo");
+    Account.Id user2 = createAccount("user2");
+    repo = createAndOpenProject("repo");
 
     // create group and add users
     String g1 = createGroup("group1", "Administrators");
@@ -1477,7 +1506,7 @@
     gApi.groups().id(g2).addMembers("user2");
 
     // create a change
-    Change change1 = insert(repo, newChange(repo), user1);
+    Change change1 = insert("repo", newChange(repo), user1);
 
     // post a review with user1
     requestContext.setContext(newRequestContext(user1));
@@ -1490,8 +1519,8 @@
     requestContext.setContext(newRequestContext(userId));
     assertQuery("label:Code-Review=+1,group1", change1);
     assertQuery("label:Code-Review=+1,group=group1", change1);
-    assertQuery("label:Code-Review=+1,user=user1", change1);
-    assertQuery("label:Code-Review=+1,user=user2");
+    assertQuery("label:Code-Review=+1,user=" + user1, change1);
+    assertQuery("label:Code-Review=+1,user=" + user2);
     assertQuery("label:Code-Review=+1,group=group2");
   }
 
@@ -1499,7 +1528,7 @@
   public void byLabelExternalGroup() throws Exception {
     Account.Id user1 = createAccount("user1");
     Account.Id user2 = createAccount("user2");
-    TestRepository<InMemoryRepositoryManager.Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
 
     // create group and add users
     AccountGroup.UUID external_group1 = AccountGroup.uuid("testbackend:group1");
@@ -1511,8 +1540,8 @@
     testGroupBackend.setMembershipsOf(
         user2, new ListGroupMembership(ImmutableList.of(external_group2)));
 
-    Change change1 = insert(repo, newChange(repo), user1);
-    Change change2 = insert(repo, newChange(repo), user1);
+    Change change1 = insert("repo", newChange(repo), user1);
+    Change change2 = insert("repo", newChange(repo), user1);
 
     // post a review with user1 and other_user
     requestContext.setContext(newRequestContext(user1));
@@ -1528,18 +1557,18 @@
 
     assertQuery("label:Code-Review=+1," + external_group1.get(), change1);
     assertQuery("label:Code-Review=+1,group=" + external_group1.get(), change1);
-    assertQuery("label:Code-Review=+1,user=user1", change1);
-    assertQuery("label:Code-Review=+1,user=user2");
+    assertQuery("label:Code-Review=+1,user=" + user1, change1);
+    assertQuery("label:Code-Review=+1,user=" + user2);
     assertQuery("label:Code-Review=+1,group=" + external_group2.get());
   }
 
   @Test
   public void limit() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     Change last = null;
     int n = 5;
     for (int i = 0; i < n; i++) {
-      last = insert(repo, newChange(repo));
+      last = insert("repo", newChange(repo));
     }
 
     for (int i = 1; i <= n + 2; i++) {
@@ -1564,10 +1593,10 @@
 
   @Test
   public void start() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     List<Change> changes = new ArrayList<>();
     for (int i = 0; i < 2; i++) {
-      changes.add(insert(repo, newChange(repo)));
+      changes.add(insert("repo", newChange(repo)));
     }
 
     assertQuery("status:new", changes.get(1), changes.get(0));
@@ -1584,10 +1613,10 @@
 
   @Test
   public void startWithLimit() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     List<Change> changes = new ArrayList<>();
     for (int i = 0; i < 3; i++) {
-      changes.add(insert(repo, newChange(repo)));
+      changes.add(insert("repo", newChange(repo)));
     }
 
     assertQuery("status:new limit:2", changes.get(2), changes.get(1));
@@ -1598,8 +1627,8 @@
 
   @Test
   public void maxPages() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change = insert(repo, newChange(repo));
+    repo = createAndOpenProject("repo");
+    Change change = insert("repo", newChange(repo));
 
     QueryRequest query = newQuery("status:new").withLimit(10);
     assertQuery(query, change);
@@ -1614,12 +1643,12 @@
   @Test
   public void updateOrder() throws Exception {
     resetTimeWithClockStep(2, MINUTES);
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     List<ChangeInserter> inserters = new ArrayList<>();
     List<Change> changes = new ArrayList<>();
     for (int i = 0; i < 5; i++) {
       inserters.add(newChange(repo));
-      changes.add(insert(repo, inserters.get(i)));
+      changes.add(insert("repo", inserters.get(i)));
     }
 
     for (int i : ImmutableList.of(2, 0, 1, 4, 3)) {
@@ -1641,10 +1670,10 @@
   @Test
   public void updatedOrder() throws Exception {
     resetTimeWithClockStep(1, SECONDS);
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     ChangeInserter ins1 = newChange(repo);
-    Change change1 = insert(repo, ins1);
-    Change change2 = insert(repo, newChange(repo));
+    Change change1 = insert("repo", ins1);
+    Change change2 = insert("repo", newChange(repo));
 
     assertThat(lastUpdatedMs(change1)).isLessThan(lastUpdatedMs(change2));
     assertQuery("status:new", change2, change1);
@@ -1662,12 +1691,12 @@
 
   @Test
   public void filterOutMoreThanOnePageOfResults() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change = insert(repo, newChange(repo), userId);
+    repo = createAndOpenProject("repo");
+    Change change = insert("repo", newChange(repo), userId);
     Account.Id user2 =
         accountManager.authenticate(authRequestFactory.createForUser("anotheruser")).getAccountId();
     for (int i = 0; i < 5; i++) {
-      insert(repo, newChange(repo), user2);
+      insert("repo", newChange(repo), user2);
     }
 
     assertQuery("status:new ownerin:Administrators", change);
@@ -1676,11 +1705,11 @@
 
   @Test
   public void filterOutAllResults() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     Account.Id user2 =
         accountManager.authenticate(authRequestFactory.createForUser("anotheruser")).getAccountId();
     for (int i = 0; i < 5; i++) {
-      insert(repo, newChange(repo), user2);
+      insert("repo", newChange(repo), user2);
     }
 
     assertQuery("status:new ownerin:Administrators");
@@ -1689,8 +1718,8 @@
 
   @Test
   public void byFileExact() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change = insert(repo, newChangeWithFiles(repo, "dir/file1", "dir/file2"));
+    repo = createAndOpenProject("repo");
+    Change change = insert("repo", newChangeWithFiles(repo, "dir/file1", "dir/file2"));
 
     assertQuery("file:file");
     assertQuery("file:dir", change);
@@ -1702,8 +1731,8 @@
 
   @Test
   public void byFileRegex() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change = insert(repo, newChangeWithFiles(repo, "dir/file1", "dir/file2"));
+    repo = createAndOpenProject("repo");
+    Change change = insert("repo", newChangeWithFiles(repo, "dir/file1", "dir/file2"));
 
     assertQuery("file:.*file.*");
     assertQuery("file:^file.*"); // Whole path only.
@@ -1712,8 +1741,8 @@
 
   @Test
   public void byPathExact() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change = insert(repo, newChangeWithFiles(repo, "dir/file1", "dir/file2"));
+    repo = createAndOpenProject("repo");
+    Change change = insert("repo", newChangeWithFiles(repo, "dir/file1", "dir/file2"));
 
     assertQuery("path:file");
     assertQuery("path:dir");
@@ -1725,8 +1754,8 @@
 
   @Test
   public void byPathRegex() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change = insert(repo, newChangeWithFiles(repo, "dir/file1", "dir/file2"));
+    repo = createAndOpenProject("repo");
+    Change change = insert("repo", newChangeWithFiles(repo, "dir/file1", "dir/file2"));
 
     assertQuery("path:.*file.*");
     assertQuery("path:^dir.file.*", change);
@@ -1734,12 +1763,12 @@
 
   @Test
   public void byExtension() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChangeWithFiles(repo, "foo.h", "foo.cc"));
-    Change change2 = insert(repo, newChangeWithFiles(repo, "bar.H", "bar.CC"));
-    Change change3 = insert(repo, newChangeWithFiles(repo, "dir/baz.h", "dir/baz.cc"));
-    Change change4 = insert(repo, newChangeWithFiles(repo, "Quux.java", "foo"));
-    Change change5 = insert(repo, newChangeWithFiles(repo, "foo"));
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChangeWithFiles(repo, "foo.h", "foo.cc"));
+    Change change2 = insert("repo", newChangeWithFiles(repo, "bar.H", "bar.CC"));
+    Change change3 = insert("repo", newChangeWithFiles(repo, "dir/baz.h", "dir/baz.cc"));
+    Change change4 = insert("repo", newChangeWithFiles(repo, "Quux.java", "foo"));
+    Change change5 = insert("repo", newChangeWithFiles(repo, "foo"));
 
     assertQuery("extension:java", change4);
     assertQuery("ext:java", change4);
@@ -1755,14 +1784,14 @@
 
   @Test
   public void byOnlyExtensions() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChangeWithFiles(repo, "foo.h", "foo.cc", "bar.cc"));
-    Change change2 = insert(repo, newChangeWithFiles(repo, "bar.H", "bar.CC", "foo.H"));
-    Change change3 = insert(repo, newChangeWithFiles(repo, "foo.CC", "bar.cc"));
-    Change change4 = insert(repo, newChangeWithFiles(repo, "dir/baz.h", "dir/baz.cc"));
-    Change change5 = insert(repo, newChangeWithFiles(repo, "Quux.java"));
-    Change change6 = insert(repo, newChangeWithFiles(repo, "foo.txt", "foo"));
-    Change change7 = insert(repo, newChangeWithFiles(repo, "foo"));
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChangeWithFiles(repo, "foo.h", "foo.cc", "bar.cc"));
+    Change change2 = insert("repo", newChangeWithFiles(repo, "bar.H", "bar.CC", "foo.H"));
+    Change change3 = insert("repo", newChangeWithFiles(repo, "foo.CC", "bar.cc"));
+    Change change4 = insert("repo", newChangeWithFiles(repo, "dir/baz.h", "dir/baz.cc"));
+    Change change5 = insert("repo", newChangeWithFiles(repo, "Quux.java"));
+    Change change6 = insert("repo", newChangeWithFiles(repo, "foo.txt", "foo"));
+    Change change7 = insert("repo", newChangeWithFiles(repo, "foo"));
 
     // case doesn't matter
     assertQuery("onlyextensions:cc,h", change4, change2, change1);
@@ -1802,23 +1831,23 @@
 
   @Test
   public void byFooter() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     RevCommit commit1 = repo.parseBody(repo.commit().message("Test\n\nfoo: bar").create());
-    Change change1 = insert(repo, newChangeForCommit(repo, commit1));
+    Change change1 = insert("repo", newChangeForCommit(repo, commit1));
     RevCommit commit2 = repo.parseBody(repo.commit().message("Test\n\nfoo: baz").create());
-    Change change2 = insert(repo, newChangeForCommit(repo, commit2));
+    Change change2 = insert("repo", newChangeForCommit(repo, commit2));
     RevCommit commit3 = repo.parseBody(repo.commit().message("Test\n\nfoo: bar\nfoo:baz").create());
-    Change change3 = insert(repo, newChangeForCommit(repo, commit3));
+    Change change3 = insert("repo", newChangeForCommit(repo, commit3));
     RevCommit commit4 = repo.parseBody(repo.commit().message("Test\n\nfoo: bar=baz").create());
-    Change change4 = insert(repo, newChangeForCommit(repo, commit4));
+    Change change4 = insert("repo", newChangeForCommit(repo, commit4));
 
     // create a changes with lines that look like footers, but which are not
     RevCommit commit5 =
         repo.parseBody(
             repo.commit().message("Test\n\nfoo: bar\n\nfoo=bar").insertChangeId().create());
-    Change change5 = insert(repo, newChangeForCommit(repo, commit5));
+    Change change5 = insert("repo", newChangeForCommit(repo, commit5));
     RevCommit commit6 = repo.parseBody(repo.commit().message("Test\n\na=b: c").create());
-    insert(repo, newChangeForCommit(repo, commit6));
+    insert("repo", newChangeForCommit(repo, commit6));
 
     // matching by 'key=value' works
     assertQuery("footer:foo=bar", change3, change1);
@@ -1852,15 +1881,15 @@
   @Test
   public void byFooterName() throws Exception {
     assume().that(getSchema().hasField(ChangeField.FOOTER_NAME)).isTrue();
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     RevCommit commit1 = repo.parseBody(repo.commit().message("Test\n\nfoo: bar").create());
-    Change change1 = insert(repo, newChangeForCommit(repo, commit1));
+    Change change1 = insert("repo", newChangeForCommit(repo, commit1));
     RevCommit commit2 = repo.parseBody(repo.commit().message("Test\n\nBaR: baz").create());
-    Change change2 = insert(repo, newChangeForCommit(repo, commit2));
+    Change change2 = insert("repo", newChangeForCommit(repo, commit2));
 
     // create a changes with lines that look like footers, but which are not
     RevCommit commit6 = repo.parseBody(repo.commit().message("Test\n\na=b: c").create());
-    insert(repo, newChangeForCommit(repo, commit6));
+    insert("repo", newChangeForCommit(repo, commit6));
 
     // matching by 'key=value' works
     assertQuery("hasfooter:foo", change1);
@@ -1872,14 +1901,14 @@
 
   @Test
   public void byDirectory() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChangeWithFiles(repo, "src/foo.h", "src/foo.cc"));
-    Change change2 = insert(repo, newChangeWithFiles(repo, "src/java/foo.java", "src/js/bar.js"));
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChangeWithFiles(repo, "src/foo.h", "src/foo.cc"));
+    Change change2 = insert("repo", newChangeWithFiles(repo, "src/java/foo.java", "src/js/bar.js"));
     Change change3 =
-        insert(repo, newChangeWithFiles(repo, "documentation/training/slides/README.txt"));
-    Change change4 = insert(repo, newChangeWithFiles(repo, "a.txt"));
-    Change change5 = insert(repo, newChangeWithFiles(repo, "a/b/c/d/e/foo.txt"));
-    Change change6 = insert(repo, newChangeWithFiles(repo, "all/caps/DIRECTORY/file.txt"));
+        insert("repo", newChangeWithFiles(repo, "documentation/training/slides/README.txt"));
+    Change change4 = insert("repo", newChangeWithFiles(repo, "a.txt"));
+    Change change5 = insert("repo", newChangeWithFiles(repo, "a/b/c/d/e/foo.txt"));
+    Change change6 = insert("repo", newChangeWithFiles(repo, "all/caps/DIRECTORY/file.txt"));
 
     // matching by directory prefix works
     assertQuery("directory:src", change2, change1);
@@ -1940,10 +1969,10 @@
 
   @Test
   public void byDirectoryRegex() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChangeWithFiles(repo, "src/java/foo.java", "src/js/bar.js"));
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChangeWithFiles(repo, "src/java/foo.java", "src/js/bar.js"));
     Change change2 =
-        insert(repo, newChangeWithFiles(repo, "documentation/training/slides/README.txt"));
+        insert("repo", newChangeWithFiles(repo, "documentation/training/slides/README.txt"));
 
     // match by regexp
     assertQuery("directory:^.*va.*", change1);
@@ -1953,9 +1982,9 @@
 
   @Test
   public void byComment() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     ChangeInserter ins = newChange(repo);
-    Change change = insert(repo, ins);
+    Change change = insert("repo", ins);
 
     ReviewInput input = new ReviewInput();
     input.message = "toplevel";
@@ -1983,11 +2012,11 @@
   public void byAge() throws Exception {
     long thirtyHoursInMs = MILLISECONDS.convert(30, HOURS);
     resetTimeWithClockStep(thirtyHoursInMs, MILLISECONDS);
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     long startMs = TestTimeUtil.START.toEpochMilli();
-    Change change1 = insert(repo, newChange(repo), null, Instant.ofEpochMilli(startMs));
+    Change change1 = insert("repo", newChange(repo), null, Instant.ofEpochMilli(startMs));
     Change change2 =
-        insert(repo, newChange(repo), null, Instant.ofEpochMilli(startMs + thirtyHoursInMs));
+        insert("repo", newChange(repo), null, Instant.ofEpochMilli(startMs + thirtyHoursInMs));
 
     // Stop time so age queries use the same endpoint.
     TestTimeUtil.setClockStep(0, MILLISECONDS);
@@ -2024,11 +2053,11 @@
   public void byBeforeUntil() throws Exception {
     long thirtyHoursInMs = MILLISECONDS.convert(30, HOURS);
     resetTimeWithClockStep(thirtyHoursInMs, MILLISECONDS);
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     long startMs = TestTimeUtil.START.toEpochMilli();
-    Change change1 = insert(repo, newChange(repo), null, Instant.ofEpochMilli(startMs));
+    Change change1 = insert("repo", newChange(repo), null, Instant.ofEpochMilli(startMs));
     Change change2 =
-        insert(repo, newChange(repo), null, Instant.ofEpochMilli(startMs + thirtyHoursInMs));
+        insert("repo", newChange(repo), null, Instant.ofEpochMilli(startMs + thirtyHoursInMs));
     TestTimeUtil.setClockStep(0, MILLISECONDS);
 
     // Change1 was last updated on 2009-09-30 21:00:00 -0000
@@ -2076,11 +2105,11 @@
   public void byAfterSince() throws Exception {
     long thirtyHoursInMs = MILLISECONDS.convert(30, HOURS);
     resetTimeWithClockStep(thirtyHoursInMs, MILLISECONDS);
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     long startMs = TestTimeUtil.START.toEpochMilli();
-    Change change1 = insert(repo, newChange(repo), null, Instant.ofEpochMilli(startMs));
+    Change change1 = insert("repo", newChange(repo), null, Instant.ofEpochMilli(startMs));
     Change change2 =
-        insert(repo, newChange(repo), null, Instant.ofEpochMilli(startMs + thirtyHoursInMs));
+        insert("repo", newChange(repo), null, Instant.ofEpochMilli(startMs + thirtyHoursInMs));
     TestTimeUtil.setClockStep(0, MILLISECONDS);
 
     // Change1 was last updated on 2009-09-30 21:00:00 -0000
@@ -2120,12 +2149,12 @@
 
     // Stop the clock, will set time to specific test values.
     resetTimeWithClockStep(0, MILLISECONDS);
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     long startMs = TestTimeUtil.START.toEpochMilli();
     TestTimeUtil.setClock(new Timestamp(startMs));
-    Change change1 = insert(repo, newChange(repo));
-    Change change2 = insert(repo, newChange(repo));
-    Change change3 = insert(repo, newChange(repo));
+    Change change1 = insert("repo", newChange(repo));
+    Change change2 = insert("repo", newChange(repo));
+    Change change3 = insert("repo", newChange(repo));
 
     TestTimeUtil.setClock(new Timestamp(startMs + thirtyHoursInMs));
     submit(change3);
@@ -2180,12 +2209,12 @@
 
     // Stop the clock, will set time to specific test values.
     resetTimeWithClockStep(0, MILLISECONDS);
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     long startMs = TestTimeUtil.START.toEpochMilli();
     TestTimeUtil.setClock(new Timestamp(startMs));
-    Change change1 = insert(repo, newChange(repo));
-    Change change2 = insert(repo, newChange(repo));
-    Change change3 = insert(repo, newChange(repo));
+    Change change1 = insert("repo", newChange(repo));
+    Change change2 = insert("repo", newChange(repo));
+    Change change3 = insert("repo", newChange(repo));
     assertThat(TimeUtil.nowMs()).isEqualTo(startMs);
 
     TestTimeUtil.setClock(new Timestamp(startMs + thirtyHoursInMs));
@@ -2250,13 +2279,13 @@
 
     // Stop the clock, will set time to specific test values.
     resetTimeWithClockStep(0, MILLISECONDS);
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     long startMs = TestTimeUtil.START.toEpochMilli();
     TestTimeUtil.setClock(new Timestamp(startMs));
 
-    Change change1 = insert(repo, newChange(repo));
-    Change change2 = insert(repo, newChange(repo));
-    Change change3 = insert(repo, newChange(repo));
+    Change change1 = insert("repo", newChange(repo));
+    Change change2 = insert("repo", newChange(repo));
+    Change change3 = insert("repo", newChange(repo));
 
     TestTimeUtil.setClock(new Timestamp(startMs + thirtyHoursInMs));
     submit(change2);
@@ -2283,15 +2312,15 @@
 
   @Test
   public void bySize() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
 
     // added = 3, deleted = 0, delta = 3
     RevCommit commit1 = repo.parseBody(repo.commit().add("file1", "foo\n\foo\nfoo").create());
     // added = 0, deleted = 2, delta = 2
     RevCommit commit2 = repo.parseBody(repo.commit().parent(commit1).add("file1", "foo").create());
 
-    Change change1 = insert(repo, newChangeForCommit(repo, commit1));
-    Change change2 = insert(repo, newChangeForCommit(repo, commit2));
+    Change change1 = insert("repo", newChangeForCommit(repo, commit1));
+    Change change2 = insert("repo", newChangeForCommit(repo, commit2));
 
     assertQuery("added:>4");
     assertQuery("-added:<=4");
@@ -2339,9 +2368,9 @@
   }
 
   private List<Change> setUpHashtagChanges() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChange(repo));
-    Change change2 = insert(repo, newChange(repo));
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChange(repo));
+    Change change2 = insert("repo", newChange(repo));
 
     addHashtags(change1.getId(), "foo", "aaa-bbb-ccc");
     addHashtags(change2.getId(), "foo", "bar", "a tag", "ACamelCaseTag");
@@ -2388,10 +2417,10 @@
 
   @Test
   public void byHashtagRegex() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChange(repo));
-    Change change2 = insert(repo, newChange(repo));
-    Change change3 = insert(repo, newChange(repo));
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChange(repo));
+    Change change2 = insert("repo", newChange(repo));
+    Change change3 = insert("repo", newChange(repo));
     addHashtags(change1.getId(), "feature1");
     addHashtags(change1.getId(), "trending");
     addHashtags(change2.getId(), "Cherrypick-feature1");
@@ -2404,27 +2433,27 @@
 
   @Test
   public void byDefault() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
 
-    Change change1 = insert(repo, newChange(repo));
+    Change change1 = insert("repo", newChange(repo));
 
     RevCommit commit2 = repo.parseBody(repo.commit().message("foosubject").create());
-    Change change2 = insert(repo, newChangeForCommit(repo, commit2));
+    Change change2 = insert("repo", newChangeForCommit(repo, commit2));
 
     RevCommit commit3 = repo.parseBody(repo.commit().add("Foo.java", "foo contents").create());
-    Change change3 = insert(repo, newChangeForCommit(repo, commit3));
+    Change change3 = insert("repo", newChangeForCommit(repo, commit3));
 
     ChangeInserter ins4 = newChange(repo);
-    Change change4 = insert(repo, ins4);
+    Change change4 = insert("repo", ins4);
     ReviewInput ri4 = new ReviewInput();
     ri4.message = "toplevel";
     ri4.labels = ImmutableMap.of("Code-Review", (short) 1);
     gApi.changes().id(change4.getId().get()).current().review(ri4);
 
     ChangeInserter ins5 = newChangeWithTopic(repo, "feature5");
-    Change change5 = insert(repo, ins5);
+    Change change5 = insert("repo", ins5);
 
-    Change change6 = insert(repo, newChangeForBranch(repo, "branch6"));
+    Change change6 = insert("repo", newChangeForBranch(repo, "branch6"));
 
     assertQuery(change1.getId().get(), change1);
     assertQuery(ChangeTriplet.format(change1), change1);
@@ -2445,18 +2474,18 @@
 
   @Test
   public void byDefaultWithCommitPrefix() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     RevCommit commit = repo.parseBody(repo.commit().message("message").create());
-    Change change = insert(repo, newChangeForCommit(repo, commit));
+    Change change = insert("repo", newChangeForCommit(repo, commit));
 
     assertQuery(commit.getId().getName().substring(0, 6), change);
   }
 
   @Test
   public void visible() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChange(repo));
-    Change change2 = insert(repo, newChangePrivate(repo));
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChange(repo));
+    Change change2 = insert("repo", newChangePrivate(repo));
 
     String q = "project:repo";
 
@@ -2510,8 +2539,8 @@
 
     // Switch to user3
     requestContext.setContext(newRequestContext(user3));
-    Change change3 = insert(repo, newChange(repo), user3);
-    Change change4 = insert(repo, newChangePrivate(repo), user3);
+    Change change3 = insert("repo", newChange(repo), user3);
+    Change change4 = insert("repo", newChangePrivate(repo), user3);
 
     // User3 can see both their changes and the first user's change
     assertQuery(q + " visibleto:" + user3.get(), change4, change3, change1);
@@ -2551,9 +2580,9 @@
 
   @Test
   public void visibleToSelf() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChange(repo));
-    Change change2 = insert(repo, newChange(repo));
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChange(repo));
+    Change change2 = insert("repo", newChange(repo));
 
     gApi.changes().id(change2.getChangeId()).setPrivate(true, "private");
 
@@ -2569,16 +2598,12 @@
 
   @Test
   public void byCommentBy() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChange(repo));
-    Change change2 = insert(repo, newChange(repo));
 
-    int user2 =
-        accountManager
-            .authenticate(authRequestFactory.createForUser("anotheruser"))
-            .getAccountId()
-            .get();
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChange(repo));
+    Change change2 = insert("repo", newChange(repo));
 
+    Account.Id user2 = createAccount("anotheruser");
     ReviewInput input = new ReviewInput();
     input.message = "toplevel";
     ReviewInput.CommentInput comment = new ReviewInput.CommentInput();
@@ -2599,8 +2624,8 @@
   public void bySubmitRuleResult() throws Exception {
     try (Registration registration =
         extensionRegistry.newRegistration().add(new FakeSubmitRule())) {
-      TestRepository<Repo> repo = createProject("repo");
-      Change change = insert(repo, newChange(repo));
+      repo = createAndOpenProject("repo");
+      Change change = insert("repo", newChange(repo));
       // The fake submit rule exports its ruleName as "FakeSubmitRule"
       assertQuery("rule:FakeSubmitRule");
 
@@ -2619,17 +2644,17 @@
   public void byNonExistingSubmitRule_returnsEmpty() throws Exception {
     try (Registration registration =
         extensionRegistry.newRegistration().add(new FakeSubmitRule())) {
-      TestRepository<Repo> repo = createProject("repo");
-      insert(repo, newChange(repo));
+      repo = createAndOpenProject("repo");
+      insert("repo", newChange(repo));
       assertQuery("rule:non-existent-rule");
     }
   }
 
   @Test
   public void byHasDraft() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChange(repo));
-    Change change2 = insert(repo, newChange(repo));
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChange(repo));
+    Change change2 = insert("repo", newChange(repo));
 
     assertQuery("has:draft");
 
@@ -2661,8 +2686,8 @@
    */
   public void byHasDraftExcludesZombieDrafts() throws Exception {
     Project.NameKey project = Project.nameKey("repo");
-    TestRepository<Repo> repo = createProject(project.get());
-    Change change = insert(repo, newChange(repo));
+    repo = createAndOpenProject(project.get());
+    Change change = insert("repo", newChange(repo));
     Change.Id id = change.getId();
 
     DraftInput in = new DraftInput();
@@ -2674,7 +2699,7 @@
     assertQuery("has:draft", change);
     assertQuery("commentby:" + userId);
 
-    try (TestRepository<Repo> allUsers =
+    try (TestRepository<Repository> allUsers =
         new TestRepository<>(repoManager.openRepository(allUsersName))) {
       Ref draftsRef = allUsers.getRepository().exactRef(RefNames.refsDraftComments(id, userId));
       assertThat(draftsRef).isNotNull();
@@ -2698,15 +2723,15 @@
 
   @Test
   public void byHasDraftWithManyDrafts() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     Change[] changesWithDrafts = new Change[30];
 
     // unrelated change not shown in the result.
-    insert(repo, newChange(repo));
+    insert("repo", newChange(repo));
 
     for (int i = 0; i < changesWithDrafts.length; i++) {
       // put the changes in reverse order since this is the order we receive them from the index.
-      changesWithDrafts[changesWithDrafts.length - 1 - i] = insert(repo, newChange(repo));
+      changesWithDrafts[changesWithDrafts.length - 1 - i] = insert("repo", newChange(repo));
       DraftInput in = new DraftInput();
       in.line = 1;
       in.message = "nit: trailing whitespace";
@@ -2726,10 +2751,10 @@
 
   @Test
   public void byStarredBy() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChange(repo));
-    Change change2 = insert(repo, newChange(repo));
-    insert(repo, newChange(repo));
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChange(repo));
+    Change change2 = insert("repo", newChange(repo));
+    insert("repo", newChange(repo));
 
     gApi.accounts().self().starChange(change1.getId().toString());
     gApi.accounts().self().starChange(change2.getId().toString());
@@ -2745,8 +2770,8 @@
 
   @Test
   public void byStar() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChangeWithStatus(repo, Change.Status.MERGED));
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChangeWithStatus(repo, Change.Status.MERGED));
 
     Account.Id user2 =
         accountManager.authenticate(authRequestFactory.createForUser("anotheruser")).getAccountId();
@@ -2761,11 +2786,11 @@
 
   @Test
   public void byStarWithManyStars() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     Change[] changesWithDrafts = new Change[30];
     for (int i = 0; i < changesWithDrafts.length; i++) {
       // put the changes in reverse order since this is the order we receive them from the index.
-      changesWithDrafts[changesWithDrafts.length - 1 - i] = insert(repo, newChange(repo));
+      changesWithDrafts[changesWithDrafts.length - 1 - i] = insert("repo", newChange(repo));
 
       // star the change
       gApi.accounts()
@@ -2779,12 +2804,12 @@
 
   @Test
   public void byFrom() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChange(repo));
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChange(repo));
 
     Account.Id user2 =
         accountManager.authenticate(authRequestFactory.createForUser("anotheruser")).getAccountId();
-    Change change2 = insert(repo, newChange(repo), user2);
+    Change change2 = insert("repo", newChange(repo), user2);
 
     ReviewInput input = new ReviewInput();
     input.message = "toplevel";
@@ -2800,7 +2825,7 @@
 
   @Test
   public void conflicts() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     RevCommit commit1 =
         repo.parseBody(
             repo.commit()
@@ -2812,10 +2837,10 @@
     RevCommit commit3 =
         repo.parseBody(repo.commit().add("dir/file2", "contents2 different").create());
     RevCommit commit4 = repo.parseBody(repo.commit().add("file4", "contents4").create());
-    Change change1 = insert(repo, newChangeForCommit(repo, commit1));
-    Change change2 = insert(repo, newChangeForCommit(repo, commit2));
-    Change change3 = insert(repo, newChangeForCommit(repo, commit3));
-    Change change4 = insert(repo, newChangeForCommit(repo, commit4));
+    Change change1 = insert("repo", newChangeForCommit(repo, commit1));
+    Change change2 = insert("repo", newChangeForCommit(repo, commit2));
+    Change change3 = insert("repo", newChangeForCommit(repo, commit3));
+    Change change4 = insert("repo", newChangeForCommit(repo, commit4));
 
     assertQuery("conflicts:" + change1.getId().get(), change3);
     assertQuery("conflicts:" + change2.getId().get());
@@ -2828,11 +2853,12 @@
       name = "change.mergeabilityComputationBehavior",
       value = "API_REF_UPDATED_AND_CHANGE_REINDEX")
   public void mergeable() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    assume().that(getSchema().hasField(ChangeField.MERGEABLE_SPEC)).isTrue();
+    repo = createAndOpenProject("repo");
     RevCommit commit1 = repo.parseBody(repo.commit().add("file1", "contents1").create());
     RevCommit commit2 = repo.parseBody(repo.commit().add("file1", "contents2").create());
-    Change change1 = insert(repo, newChangeForCommit(repo, commit1));
-    Change change2 = insert(repo, newChangeForCommit(repo, commit2));
+    Change change1 = insert("repo", newChangeForCommit(repo, commit1));
+    Change change2 = insert("repo", newChangeForCommit(repo, commit2));
 
     assertQuery("conflicts:" + change1.getId().get(), change2);
     assertQuery("conflicts:" + change2.getId().get(), change1);
@@ -2856,9 +2882,9 @@
   @Test
   public void cherrypick() throws Exception {
     assume().that(getSchema().hasField(ChangeField.CHERRY_PICK_SPEC)).isTrue();
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChange(repo));
-    Change change2 = insert(repo, newCherryPickChange(repo, "foo", change1.currentPatchSetId()));
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChange(repo));
+    Change change2 = insert("repo", newCherryPickChange(repo, "foo", change1.currentPatchSetId()));
 
     assertQuery("is:cherrypick", change2);
     assertQuery("-is:cherrypick", change1);
@@ -2867,14 +2893,14 @@
   @Test
   public void merge() throws Exception {
     assume().that(getSchema().hasField(ChangeField.MERGE_SPEC)).isTrue();
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     RevCommit commit1 = repo.parseBody(repo.commit().add("file1", "contents1").create());
     RevCommit commit2 = repo.parseBody(repo.commit().add("file1", "contents2").create());
     RevCommit commit3 =
         repo.parseBody(repo.commit().parent(commit2).add("file1", "contents3").create());
-    Change change1 = insert(repo, newChangeForCommit(repo, commit1));
-    Change change2 = insert(repo, newChangeForCommit(repo, commit2));
-    Change change3 = insert(repo, newChangeForCommit(repo, commit3));
+    Change change1 = insert("repo", newChangeForCommit(repo, commit1));
+    Change change2 = insert("repo", newChangeForCommit(repo, commit2));
+    Change change3 = insert("repo", newChangeForCommit(repo, commit3));
     RevCommit mergeCommit =
         repo.branch("master")
             .commit()
@@ -2883,7 +2909,7 @@
             .parent(commit3)
             .insertChangeId()
             .create();
-    Change mergeChange = insert(repo, newChangeForCommit(repo, mergeCommit));
+    Change mergeChange = insert("repo", newChangeForCommit(repo, mergeCommit));
 
     assertQuery("status:open is:merge", mergeChange);
     assertQuery("status:open -is:merge", change3, change2, change1);
@@ -2893,10 +2919,10 @@
   @Test
   public void reviewedBy() throws Exception {
     resetTimeWithClockStep(2, MINUTES);
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChange(repo));
-    Change change2 = insert(repo, newChange(repo));
-    Change change3 = insert(repo, newChange(repo));
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChange(repo));
+    Change change2 = insert("repo", newChange(repo));
+    Change change3 = insert("repo", newChange(repo));
 
     gApi.changes().id(change1.getId().get()).current().review(new ReviewInput().message("comment"));
 
@@ -2907,7 +2933,7 @@
     gApi.changes().id(change2.getId().get()).current().review(new ReviewInput().message("comment"));
 
     PatchSet.Id ps3_1 = change3.currentPatchSetId();
-    change3 = newPatchSet(repo, change3, user, /* message= */ Optional.empty());
+    change3 = newPatchSet("repo", change3, user, /* message= */ Optional.empty());
     assertThat(change3.currentPatchSetId()).isNotEqualTo(ps3_1);
     // Response to previous patch set still counts as reviewing.
     gApi.changes()
@@ -2934,11 +2960,11 @@
   @Test
   public void reviewerAndCc() throws Exception {
     Account.Id user1 = createAccount("user1");
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChange(repo));
-    Change change2 = insert(repo, newChange(repo));
-    Change change3 = insert(repo, newChange(repo));
-    insert(repo, newChange(repo));
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChange(repo));
+    Change change2 = insert("repo", newChange(repo));
+    Change change3 = insert("repo", newChange(repo));
+    insert("repo", newChange(repo));
 
     ReviewerInput rin = new ReviewerInput();
     rin.reviewer = user1.toString();
@@ -2965,11 +2991,11 @@
 
   @Test
   public void byReviewed() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     Account.Id otherUser =
         accountManager.authenticate(authRequestFactory.createForUser("anotheruser")).getAccountId();
-    Change change1 = insert(repo, newChange(repo));
-    Change change2 = insert(repo, newChange(repo));
+    Change change1 = insert("repo", newChange(repo));
+    Change change2 = insert("repo", newChange(repo));
 
     assertQuery("is:reviewed");
     assertQuery("status:reviewed");
@@ -2993,11 +3019,11 @@
         accountManager.authenticate(authRequestFactory.createForUser("user2")).getAccountId();
     Account.Id user3 =
         accountManager.authenticate(authRequestFactory.createForUser("user3")).getAccountId();
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
 
-    Change change1 = insert(repo, newChange(repo));
-    Change change2 = insert(repo, newChange(repo));
-    Change change3 = insert(repo, newChange(repo));
+    Change change1 = insert("repo", newChange(repo));
+    Change change2 = insert("repo", newChange(repo));
+    Change change3 = insert("repo", newChange(repo));
 
     ReviewerInput rin = new ReviewerInput();
     rin.reviewer = user1.toString();
@@ -3037,7 +3063,7 @@
   @Test
   public void reviewerAndCcByEmail() throws Exception {
     Project.NameKey project = Project.nameKey("repo");
-    TestRepository<Repo> repo = createProject(project.get());
+    repo = createAndOpenProject(project.get());
     ConfigInput conf = new ConfigInput();
     conf.enableReviewerByEmail = InheritableBoolean.TRUE;
     gApi.projects().name(project.get()).config(conf);
@@ -3045,9 +3071,9 @@
     String userByEmail = "un.registered@reviewer.com";
     String userByEmailWithName = "John Doe <" + userByEmail + ">";
 
-    Change change1 = insert(repo, newChange(repo));
-    Change change2 = insert(repo, newChange(repo));
-    insert(repo, newChange(repo));
+    Change change1 = insert("repo", newChange(repo));
+    Change change2 = insert("repo", newChange(repo));
+    insert("repo", newChange(repo));
 
     ReviewerInput rin = new ReviewerInput();
     rin.reviewer = userByEmailWithName;
@@ -3070,16 +3096,16 @@
   @Test
   public void reviewerAndCcByEmailWithQueryForDifferentUser() throws Exception {
     Project.NameKey project = Project.nameKey("repo");
-    TestRepository<Repo> repo = createProject(project.get());
+    repo = createAndOpenProject(project.get());
     ConfigInput conf = new ConfigInput();
     conf.enableReviewerByEmail = InheritableBoolean.TRUE;
     gApi.projects().name(project.get()).config(conf);
 
     String userByEmail = "John Doe <un.registered@reviewer.com>";
 
-    Change change1 = insert(repo, newChange(repo));
-    Change change2 = insert(repo, newChange(repo));
-    insert(repo, newChange(repo));
+    Change change1 = insert("repo", newChange(repo));
+    Change change2 = insert("repo", newChange(repo));
+    insert("repo", newChange(repo));
 
     ReviewerInput rin = new ReviewerInput();
     rin.reviewer = userByEmail;
@@ -3098,9 +3124,9 @@
   @Test
   public void submitRecords() throws Exception {
     Account.Id user1 = createAccount("user1");
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChange(repo));
-    Change change2 = insert(repo, newChange(repo));
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChange(repo));
+    Change change2 = insert("repo", newChange(repo));
 
     gApi.changes().id(change1.getId().get()).current().review(ReviewInput.approve());
     requestContext.setContext(newRequestContext(user1));
@@ -3111,7 +3137,7 @@
     assertQuery("-is:submittable", change2);
 
     assertQuery("label:CodE-RevieW=ok", change1);
-    assertQuery("label:CodE-RevieW=ok,user=user", change1);
+    assertQuery("label:CodE-RevieW=ok,user=" + userAccount.preferredEmail(), change1);
     assertQuery("label:CodE-RevieW=ok,Administrators", change1);
     assertQuery("label:CodE-RevieW=ok,group=Administrators", change1);
     assertQuery("label:CodE-RevieW=ok,owner", change1);
@@ -3130,10 +3156,10 @@
   public void hasEdit() throws Exception {
     Account.Id user1 = createAccount("user1");
     Account.Id user2 = createAccount("user2");
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChange(repo));
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChange(repo));
     String changeId1 = change1.getKey().get();
-    Change change2 = insert(repo, newChange(repo));
+    Change change2 = insert("repo", newChange(repo));
     String changeId2 = change2.getKey().get();
 
     requestContext.setContext(newRequestContext(user1));
@@ -3154,10 +3180,10 @@
 
   @Test
   public void byUnresolved() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChange(repo));
-    Change change2 = insert(repo, newChange(repo));
-    Change change3 = insert(repo, newChange(repo));
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChange(repo));
+    Change change2 = insert("repo", newChange(repo));
+    Change change3 = insert("repo", newChange(repo));
 
     // Change1 has one resolved comment (unresolvedcount = 0)
     // Change2 has one unresolved comment (unresolvedcount = 1)
@@ -3185,13 +3211,13 @@
 
   @Test
   public void byCommitsOnBranchNotMerged() throws Exception {
-    TestRepository<Repo> tr = createProject("repo");
-    testByCommitsOnBranchNotMerged(tr, ImmutableSet.of());
+    createProject("repo");
+    testByCommitsOnBranchNotMerged("repo", ImmutableSet.of());
   }
 
   @Test
   public void byCommitsOnBranchNotMergedSkipsMissingChanges() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     ObjectId missing =
         repo.branch(PatchSet.id(Change.id(987654), 1).toRefName())
             .commit()
@@ -3199,41 +3225,45 @@
             .insertChangeId()
             .create()
             .copy();
-    testByCommitsOnBranchNotMerged(repo, ImmutableSet.of(missing));
+    testByCommitsOnBranchNotMerged("repo", ImmutableSet.of(missing));
   }
 
-  private void testByCommitsOnBranchNotMerged(TestRepository<Repo> repo, Collection<ObjectId> extra)
+  private void testByCommitsOnBranchNotMerged(String repo, Collection<ObjectId> extra)
       throws Exception {
     int n = 10;
     List<String> shas = new ArrayList<>(n + extra.size());
     extra.forEach(i -> shas.add(i.name()));
     List<Integer> expectedIds = new ArrayList<>(n);
     BranchNameKey dest = null;
-    for (int i = 0; i < n; i++) {
-      ChangeInserter ins = newChange(repo);
-      insert(repo, ins);
-      if (dest == null) {
-        dest = ins.getChange().getDest();
+    try (TestRepository<Repository> repository =
+        new TestRepository<>(repoManager.openRepository(Project.nameKey(repo)))) {
+      for (int i = 0; i < n; i++) {
+        ChangeInserter ins = newChange(repository);
+        insert("repo", ins);
+        if (dest == null) {
+          dest = ins.getChange().getDest();
+        }
+        shas.add(ins.getCommitId().name());
+        expectedIds.add(ins.getChange().getId().get());
       }
-      shas.add(ins.getCommitId().name());
-      expectedIds.add(ins.getChange().getId().get());
     }
-
-    for (int i = 1; i <= 11; i++) {
-      Iterable<ChangeData> cds =
-          queryProvider.get().byCommitsOnBranchNotMerged(repo.getRepository(), dest, shas, i);
-      Iterable<Integer> ids = FluentIterable.from(cds).transform(in -> in.getId().get());
-      String name = "limit " + i;
-      assertWithMessage(name).that(ids).hasSize(n);
-      assertWithMessage(name).that(ids).containsExactlyElementsIn(expectedIds);
+    try (Repository repository = repoManager.openRepository(Project.nameKey(repo))) {
+      for (int i = 1; i <= 11; i++) {
+        Iterable<ChangeData> cds =
+            queryProvider.get().byCommitsOnBranchNotMerged(repository, dest, shas, i);
+        Iterable<Integer> ids = FluentIterable.from(cds).transform(in -> in.getId().get());
+        String name = "limit " + i;
+        assertWithMessage(name).that(ids).hasSize(n);
+        assertWithMessage(name).that(ids).containsExactlyElementsIn(expectedIds);
+      }
     }
   }
 
   @Test
   public void reindexIfStale() throws Exception {
     Project.NameKey project = Project.nameKey("repo");
-    TestRepository<Repo> repo = createProject(project.get());
-    Change change = insert(repo, newChange(repo));
+    repo = createAndOpenProject(project.get());
+    Change change = insert("repo", newChange(repo));
     String changeId = change.getKey().get();
 
     Account.Id anotherUser = createAccount("another-user");
@@ -3256,14 +3286,14 @@
 
   @Test
   public void watched() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    ChangeInserter ins1 = newChangeWithStatus(repo, Change.Status.NEW);
-    Change change1 = insert(repo, ins1);
+    createProject("repo");
+    ChangeInserter ins1 = newChangeWithStatus("repo", Change.Status.NEW);
+    Change change1 = insert("repo", ins1);
 
-    TestRepository<Repo> repo2 = createProject("repo2");
+    createProject("repo2");
 
-    ChangeInserter ins2 = newChangeWithStatus(repo2, Change.Status.NEW);
-    insert(repo2, ins2);
+    ChangeInserter ins2 = newChangeWithStatus("repo2", Change.Status.NEW);
+    insert("repo2", ins2);
 
     assertQuery("is:watched");
 
@@ -3283,17 +3313,17 @@
 
   @Test
   public void trackingid() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     RevCommit commit1 =
         repo.parseBody(repo.commit().message("Change one\n\nBug:QUERY123").create());
-    Change change1 = insert(repo, newChangeForCommit(repo, commit1));
+    Change change1 = insert("repo", newChangeForCommit(repo, commit1));
     RevCommit commit2 =
         repo.parseBody(repo.commit().message("Change two\n\nIssue: Issue 16038\n").create());
-    Change change2 = insert(repo, newChangeForCommit(repo, commit2));
+    Change change2 = insert("repo", newChangeForCommit(repo, commit2));
 
     RevCommit commit3 =
         repo.parseBody(repo.commit().message("Change two\n\nGoogle-Bug-Id: b/16039\n").create());
-    Change change3 = insert(repo, newChangeForCommit(repo, commit3));
+    Change change3 = insert("repo", newChangeForCommit(repo, commit3));
 
     assertQuery("tr:QUERY123", change1);
     assertQuery("bug:QUERY123", change1);
@@ -3319,9 +3349,9 @@
 
   @Test
   public void revertOf() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     // Create two commits and revert second commit (initial commit can't be reverted)
-    Change initial = insert(repo, newChange(repo));
+    Change initial = insert("repo", newChange(repo));
     gApi.changes().id(initial.getChangeId()).current().review(ReviewInput.approve());
     gApi.changes().id(initial.getChangeId()).current().submit();
 
@@ -3336,10 +3366,10 @@
 
   @Test
   public void submissionId() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change = insert(repo, newChange(repo));
+    repo = createAndOpenProject("repo");
+    Change change = insert("repo", newChange(repo));
     // create irrelevant change
-    insert(repo, newChange(repo));
+    insert("repo", newChange(repo));
     gApi.changes().id(change.getChangeId()).current().review(ReviewInput.approve());
     gApi.changes().id(change.getChangeId()).current().submit();
     String submissionId = gApi.changes().id(change.getChangeId()).get().submissionId;
@@ -3409,9 +3439,9 @@
       return this;
     }
 
-    DashboardChangeState create(TestRepository<Repo> repo) throws Exception {
+    DashboardChangeState create(TestRepository<Repository> repo) throws Exception {
       requestContext.setContext(newRequestContext(ownerId));
-      Change change = insert(repo, newChange(repo), ownerId);
+      Change change = insert("repo", newChange(repo), ownerId);
       id = change.getId();
       ChangeApi cApi = gApi.changes().id(change.getChangeId());
       if (assigneeId != null) {
@@ -3479,7 +3509,7 @@
 
   @Test
   public void dashboardHasUnpublishedDrafts() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     Account.Id otherAccountId = createAccount("other");
     DashboardChangeState hasUnpublishedDraft =
         new DashboardChangeState(otherAccountId).draftCommentBy(user.getAccountId()).create(repo);
@@ -3497,7 +3527,7 @@
 
   @Test
   public void dashboardAssignedReviews() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     Account.Id otherAccountId = createAccount("other");
     DashboardChangeState otherOpenWip =
         new DashboardChangeState(otherAccountId).wip().assignTo(user.getAccountId()).create(repo);
@@ -3519,12 +3549,12 @@
     // Viewing another user's dashboard.
     requestContext.setContext(newRequestContext(otherAccountId));
     assertDashboardQuery(
-        user.getUserName().get(), IndexPreloadingUtil.DASHBOARD_ASSIGNED_QUERY, otherOpenWip);
+        userId.toString(), IndexPreloadingUtil.DASHBOARD_ASSIGNED_QUERY, otherOpenWip);
   }
 
   @Test
   public void dashboardWorkInProgressReviews() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     DashboardChangeState ownedOpenWip =
         new DashboardChangeState(user.getAccountId()).wip().create(repo);
 
@@ -3539,7 +3569,7 @@
 
   @Test
   public void dashboardOutgoingReviews() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     Account.Id otherAccountId = createAccount("other");
     DashboardChangeState ownedOpenReviewable =
         new DashboardChangeState(user.getAccountId()).create(repo);
@@ -3554,14 +3584,12 @@
     // Viewing another user's dashboard.
     requestContext.setContext(newRequestContext(otherAccountId));
     assertDashboardQuery(
-        user.getUserName().get(),
-        IndexPreloadingUtil.DASHBOARD_OUTGOING_QUERY,
-        ownedOpenReviewable);
+        userId.toString(), IndexPreloadingUtil.DASHBOARD_OUTGOING_QUERY, ownedOpenReviewable);
   }
 
   @Test
   public void dashboardIncomingReviews() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     Account.Id otherAccountId = createAccount("other");
     DashboardChangeState reviewingReviewable =
         new DashboardChangeState(otherAccountId).addReviewer(user.getAccountId()).create(repo);
@@ -3587,7 +3615,7 @@
     // Viewing another user's dashboard.
     requestContext.setContext(newRequestContext(otherAccountId));
     assertDashboardQuery(
-        user.getUserName().get(),
+        userId.toString(),
         IndexPreloadingUtil.DASHBOARD_INCOMING_QUERY,
         assignedReviewable,
         reviewingReviewable);
@@ -3595,7 +3623,7 @@
 
   @Test
   public void dashboardRecentlyClosedReviews() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     Account.Id otherAccountId = createAccount("other");
     DashboardChangeState mergedOwned =
         new DashboardChangeState(user.getAccountId()).mergeBy(user.getAccountId()).create(repo);
@@ -3658,7 +3686,7 @@
     // Viewing another user's dashboard.
     requestContext.setContext(newRequestContext(otherAccountId));
     assertDashboardQuery(
-        user.getUserName().get(),
+        userId.toString(),
         IndexPreloadingUtil.DASHBOARD_RECENTLY_CLOSED_QUERY,
         abandonedAssignedWip,
         abandonedAssigned,
@@ -3674,9 +3702,9 @@
   public void attentionSetIndexed() throws Exception {
     assume().that(getSchema().hasField(ChangeField.ATTENTION_SET_USERS)).isTrue();
     assume().that(getSchema().hasField(ChangeField.ATTENTION_SET_USERS_COUNT)).isTrue();
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChange(repo));
-    Change change2 = insert(repo, newChange(repo));
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChange(repo));
+    Change change2 = insert("repo", newChange(repo));
 
     AttentionSetInput input = new AttentionSetInput(userId.toString(), "some reason");
     gApi.changes().id(change1.getChangeId()).addToAttentionSet(input);
@@ -3685,7 +3713,7 @@
     assertQuery("-is:attention", change2);
     assertQuery("has:attention", change1);
     assertQuery("-has:attention", change2);
-    assertQuery("attention:" + user.getUserName().get(), change1);
+    assertQuery("attention:" + userAccount.preferredEmail(), change1);
     assertQuery("-attention:" + userId.toString(), change2);
 
     gApi.changes()
@@ -3698,8 +3726,8 @@
   @Test
   public void attentionSetStored() throws Exception {
     assume().that(getSchema().hasField(ChangeField.ATTENTION_SET_USERS)).isTrue();
-    TestRepository<Repo> repo = createProject("repo");
-    Change change = insert(repo, newChange(repo));
+    repo = createAndOpenProject("repo");
+    Change change = insert("repo", newChange(repo));
 
     AttentionSetInput input = new AttentionSetInput(userId.toString(), "reason 1");
     gApi.changes().id(change.getChangeId()).addToAttentionSet(input);
@@ -3727,29 +3755,29 @@
 
   @Test
   public void assignee() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChange(repo));
-    Change change2 = insert(repo, newChange(repo));
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChange(repo));
+    Change change2 = insert("repo", newChange(repo));
 
     AssigneeInput input = new AssigneeInput();
-    input.assignee = user.getUserName().get();
+    input.assignee = user.getAccountId().toString();
     gApi.changes().id(change1.getChangeId()).setAssignee(input);
 
     assertQuery("is:assigned", change1);
     assertQuery("-is:assigned", change2);
     assertQuery("is:unassigned", change2);
     assertQuery("-is:unassigned", change1);
-    assertQuery("assignee:" + user.getUserName().get(), change1);
-    assertQuery("-assignee:" + user.getUserName().get(), change2);
+    assertQuery("assignee:" + user.getAccountId(), change1);
+    assertQuery("-assignee:" + user.getAccountId(), change2);
   }
 
   @GerritConfig(name = "accounts.visibility", value = "NONE")
   @Test
   public void userDestination() throws Exception {
-    TestRepository<Repo> repo1 = createProject("repo1");
-    Change change1 = insert(repo1, newChange(repo1));
-    TestRepository<Repo> repo2 = createProject("repo2");
-    Change change2 = insert(repo2, newChange(repo2));
+    createProject("repo1");
+    Change change1 = insert("repo1", newChange("repo1"));
+    createProject("repo2");
+    Change change2 = insert("repo2", newChange("repo2"));
 
     assertThatQueryException("destination:foo")
         .hasMessageThat()
@@ -3763,7 +3791,7 @@
     String destination4 = "refs/heads/master\trepo3";
     String destination5 = "refs/heads/other\trepo1";
 
-    try (TestRepository<Repo> allUsers =
+    try (TestRepository<Repository> allUsers =
         new TestRepository<>(repoManager.openRepository(allUsersName))) {
       String refsUsers = RefNames.refsUsers(userId);
       allUsers.branch(refsUsers).commit().add("destinations/destination1", destination1).create();
@@ -3814,26 +3842,25 @@
     assertThatQueryException("destination:destination3,user=" + anotherUserId)
         .hasMessageThat()
         .isEqualTo("Unknown named destination: destination3");
-    assertThatQueryException("destination:destination3,user=test")
+    assertThatQueryException("destination:destination3,user=non-existent")
         .hasMessageThat()
-        .isEqualTo("Account 'test' not found");
+        .isEqualTo("Account 'non-existent' not found");
 
     requestContext.setContext(newRequestContext(anotherUserId));
-    // account 1000000 is not visible to 'anotheruser' as they are not an admin
+    // account userId is not visible to 'anotheruser' as they are not an admin
     assertThatQueryException("destination:destination3,user=" + userId)
         .hasMessageThat()
-        .isEqualTo("Account '1000000' not found");
+        .isEqualTo(String.format("Account '%s' not found", userId));
   }
 
   @GerritConfig(name = "accounts.visibility", value = "NONE")
   @Test
   public void userQuery() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChange(repo));
-    Change change2 = insert(repo, newChangeForBranch(repo, "stable"));
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChange(repo));
+    Change change2 = insert("repo", newChangeForBranch(repo, "stable"));
 
-    Account.Id anotherUserId =
-        accountManager.authenticate(authRequestFactory.createForUser("anotheruser")).getAccountId();
+    Account.Id anotherUserId = createAccount("anotheruser");
     String queryListText =
         "query1\tproject:repo\n"
             + "query2\tproject:repo status:open\n"
@@ -3845,7 +3872,7 @@
             + "query7\tproject:repo branch:stable\n"
             + "query8\tproject:repo branch:other";
 
-    try (TestRepository<Repo> allUsers =
+    try (TestRepository<Repository> allUsers =
             new TestRepository<>(repoManager.openRepository(allUsersName));
         MetaDataUpdate md = metaDataUpdateFactory.create(allUsersName);
         MetaDataUpdate anotherMd = metaDataUpdateFactory.create(allUsersName)) {
@@ -3859,19 +3886,20 @@
       anotherQueries.commit(anotherMd);
     }
 
+    assertThat(gApi.accounts().self().get()._accountId).isEqualTo(userId.get());
     assertThatQueryException("query:foo").hasMessageThat().isEqualTo("Unknown named query: foo");
     assertThatQueryException("query:query1,user=" + anotherUserId)
         .hasMessageThat()
         .isEqualTo("Unknown named query: query1");
-    assertThatQueryException("query:query1,user=test")
+    assertThatQueryException("query:query1,user=non-existent")
         .hasMessageThat()
-        .isEqualTo("Account 'test' not found");
+        .isEqualTo("Account 'non-existent' not found");
 
     requestContext.setContext(newRequestContext(anotherUserId));
     // account 1000000 is not visible to 'anotheruser' as they are not an admin
     assertThatQueryException("query:query1,user=" + userId)
         .hasMessageThat()
-        .isEqualTo("Account '1000000' not found");
+        .isEqualTo(String.format("Account '%s' not found", userId));
     requestContext.setContext(newRequestContext(userId));
 
     assertQuery("query:query1", change2, change1);
@@ -3890,16 +3918,16 @@
 
   @Test
   public void byOwnerInvalidQuery() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    insert(repo, newChange(repo), userId);
+    repo = createAndOpenProject("repo");
+    insert("repo", newChange(repo), userId);
     String nameEmail = user.asIdentifiedUser().getNameEmail();
     assertQuery("owner: \"" + nameEmail + "\"\\");
   }
 
   @Test
   public void byDeletedChange() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change = insert(repo, newChange(repo));
+    repo = createAndOpenProject("repo");
+    Change change = insert("repo", newChange(repo));
 
     String query = "change:" + change.getId();
     assertQuery(query, change);
@@ -3910,8 +3938,8 @@
 
   @Test
   public void byUrlEncodedProject() throws Exception {
-    TestRepository<Repo> repo = createProject("repo+foo");
-    Change change = insert(repo, newChange(repo));
+    repo = createAndOpenProject("repo+foo");
+    Change change = insert("repo+foo", newChange(repo));
     assertQuery("project:repo+foo", change);
   }
 
@@ -3944,9 +3972,9 @@
   @Test
   public void isPureRevert() throws Exception {
     assume().that(getSchema().hasField(ChangeField.IS_PURE_REVERT_SPEC)).isTrue();
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     // Create two commits and revert second commit (initial commit can't be reverted)
-    Change initial = insert(repo, newChange(repo));
+    Change initial = insert("repo", newChange(repo));
     gApi.changes().id(initial.getChangeId()).current().review(ReviewInput.approve());
     gApi.changes().id(initial.getChangeId()).current().submit();
 
@@ -3990,8 +4018,8 @@
     Account.Id user2 =
         accountManager.authenticate(authRequestFactory.createForUser("anotheruser")).getAccountId();
 
-    TestRepository<Repo> repo = createProject("repo");
-    Change change = insert(repo, newChange(repo));
+    repo = createAndOpenProject("repo");
+    Change change = insert("repo", newChange(repo));
     gApi.changes().id(change.getId().get()).addReviewer(user2.toString());
 
     RequestContext adminContext = requestContext.setContext(newRequestContext(user2));
@@ -4006,8 +4034,8 @@
 
   @Test
   public void none() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change = insert(repo, newChange(repo));
+    repo = createAndOpenProject("repo");
+    Change change = insert("repo", newChange(repo));
 
     assertQuery(ChangeIndexPredicate.none());
 
@@ -4027,9 +4055,10 @@
   @Test
   @GerritConfig(name = "change.mergeabilityComputationBehavior", value = "NEVER")
   public void mergeableFailsWhenNotIndexed() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    assume().that(getSchema().hasField(ChangeField.MERGE_SPEC)).isTrue();
+    repo = createAndOpenProject("repo");
     RevCommit commit1 = repo.parseBody(repo.commit().add("file1", "contents1").create());
-    insert(repo, newChangeForCommit(repo, commit1));
+    insert("repo", newChangeForCommit(repo, commit1));
 
     Throwable thrown = assertThrows(Throwable.class, () -> assertQuery("status:open is:mergeable"));
     assertThat(thrown.getCause()).isInstanceOf(QueryParseException.class);
@@ -4038,16 +4067,12 @@
         .contains("'is:mergeable' operator is not supported by server");
   }
 
-  protected ChangeInserter newChange(TestRepository<Repo> repo) throws Exception {
-    return newChange(repo, null, null, null, null, null, false, false);
-  }
-
-  protected ChangeInserter newChangeForCommit(TestRepository<Repo> repo, RevCommit commit)
+  protected ChangeInserter newChangeForCommit(TestRepository<Repository> repo, RevCommit commit)
       throws Exception {
     return newChange(repo, commit, null, null, null, null, false, false);
   }
 
-  protected ChangeInserter newChangeWithFiles(TestRepository<Repo> repo, String... paths)
+  protected ChangeInserter newChangeWithFiles(TestRepository<Repository> repo, String... paths)
       throws Exception {
     TestRepository<?>.CommitBuilder b = repo.commit().message("Change with files");
     for (String path : paths) {
@@ -4056,36 +4081,67 @@
     return newChangeForCommit(repo, repo.parseBody(b.create()));
   }
 
-  protected ChangeInserter newChangeForBranch(TestRepository<Repo> repo, String branch)
+  protected ChangeInserter newChangeForBranch(TestRepository<Repository> repo, String branch)
       throws Exception {
     return newChange(repo, null, branch, null, null, null, false, false);
   }
 
-  protected ChangeInserter newChangeWithStatus(TestRepository<Repo> repo, Change.Status status)
-      throws Exception {
+  protected ChangeInserter newChangeWithStatus(
+      TestRepository<Repository> repo, Change.Status status) throws Exception {
     return newChange(repo, null, null, status, null, null, false, false);
   }
 
-  protected ChangeInserter newChangeWithTopic(TestRepository<Repo> repo, String topic)
+  protected ChangeInserter newChangeWithStatus(String repoName, Change.Status status)
+      throws Exception {
+    return newChange(repoName, null, null, status, null, null, false, false);
+  }
+
+  protected ChangeInserter newChangeWithTopic(TestRepository<Repository> repo, String topic)
       throws Exception {
     return newChange(repo, null, null, null, topic, null, false, false);
   }
 
-  protected ChangeInserter newChangeWorkInProgress(TestRepository<Repo> repo) throws Exception {
+  protected ChangeInserter newChangeWorkInProgress(TestRepository<Repository> repo)
+      throws Exception {
     return newChange(repo, null, null, null, null, null, true, false);
   }
 
-  protected ChangeInserter newChangePrivate(TestRepository<Repo> repo) throws Exception {
+  protected ChangeInserter newChangePrivate(TestRepository<Repository> repo) throws Exception {
     return newChange(repo, null, null, null, null, null, false, true);
   }
 
   protected ChangeInserter newCherryPickChange(
-      TestRepository<Repo> repo, String branch, PatchSet.Id cherryPickOf) throws Exception {
+      TestRepository<Repository> repo, String branch, PatchSet.Id cherryPickOf) throws Exception {
     return newChange(repo, null, branch, null, null, cherryPickOf, false, true);
   }
 
+  protected ChangeInserter newChange(String repoName) throws Exception {
+    return newChange(repoName, null, null, null, null, null, false, false);
+  }
+
   protected ChangeInserter newChange(
-      TestRepository<Repo> repo,
+      String repoName,
+      @Nullable RevCommit commit,
+      @Nullable String branch,
+      @Nullable Change.Status status,
+      @Nullable String topic,
+      @Nullable PatchSet.Id cherryPickOf,
+      boolean workInProgress,
+      boolean isPrivate)
+      throws Exception {
+    try (TestRepository<Repository> repo =
+        new TestRepository<>(repoManager.openRepository(Project.nameKey(repoName)))) {
+      return newChange(
+          repo, commit, branch, status, topic, cherryPickOf, workInProgress, isPrivate);
+    }
+  }
+
+  protected ChangeInserter newChange(TestRepository<Repository> repo) throws Exception {
+    return newChange(repo, null, null, null, null, null, false, false);
+  }
+
+  protected ChangeInserter newChange(
+      TestRepository<Repository> repo,
       @Nullable RevCommit commit,
       @Nullable String branch,
       @Nullable Change.Status status,
@@ -4095,7 +4151,7 @@
       boolean isPrivate)
       throws Exception {
     if (commit == null) {
-      commit = repo.parseBody(repo.commit().message("message").create());
+      commit = repo.parseBody(repo.commit().message("initial message").create());
     }
 
     branch = MoreObjects.firstNonNull(branch, "refs/heads/master");
@@ -4104,32 +4160,32 @@
     }
 
     Change.Id id = Change.id(seq.nextChangeId());
-    ChangeInserter ins =
-        changeFactory
-            .create(id, commit, branch)
-            .setValidate(false)
-            .setStatus(status)
-            .setTopic(topic)
-            .setWorkInProgress(workInProgress)
-            .setPrivate(isPrivate)
-            .setCherryPickOf(cherryPickOf);
-    return ins;
+    return changeFactory
+        .create(id, commit, branch)
+        .setValidate(false)
+        .setStatus(status)
+        .setTopic(topic)
+        .setWorkInProgress(workInProgress)
+        .setPrivate(isPrivate)
+        .setCherryPickOf(cherryPickOf);
   }
 
-  protected Change insert(TestRepository<Repo> repo, ChangeInserter ins) throws Exception {
-    return insert(repo, ins, null, TimeUtil.now());
-  }
-
-  protected Change insert(TestRepository<Repo> repo, ChangeInserter ins, @Nullable Account.Id owner)
+  @CanIgnoreReturnValue
+  protected Change insert(String repoName, ChangeInserter ins, @Nullable Account.Id owner)
       throws Exception {
-    return insert(repo, ins, owner, TimeUtil.now());
+    return insert(repoName, ins, owner, TimeUtil.now());
   }
 
+  @CanIgnoreReturnValue
+  protected Change insert(String repoName, ChangeInserter ins) throws Exception {
+    return insert(repoName, ins, null, TimeUtil.now());
+  }
+
+  @CanIgnoreReturnValue
   protected Change insert(
-      TestRepository<Repo> repo, ChangeInserter ins, @Nullable Account.Id owner, Instant createdOn)
+      String repoName, ChangeInserter ins, @Nullable Account.Id owner, Instant createdOn)
       throws Exception {
-    Project.NameKey project =
-        Project.nameKey(repo.getRepository().getDescription().getRepositoryName());
+    Project.NameKey project = Project.nameKey(repoName);
     Account.Id ownerId = owner != null ? owner : userId;
     IdentifiedUser user = userFactory.create(ownerId);
     try (BatchUpdate bu = updateFactory.create(project, user, createdOn)) {
@@ -4140,34 +4196,36 @@
   }
 
   protected Change newPatchSet(
-      TestRepository<Repo> repo, Change c, CurrentUser user, Optional<String> message)
-      throws Exception {
-    // Add a new file so the patch set is not a trivial rebase, to avoid default
-    // Code-Review label copying.
-    int n = c.currentPatchSetId().get() + 1;
-    RevCommit commit =
-        repo.parseBody(
-            repo.commit()
-                .message(message.orElse("message"))
-                .add("file" + n, "contents " + n)
-                .create());
+      String repoName, Change c, CurrentUser user, Optional<String> message) throws Exception {
+    try (TestRepository<Repository> repo =
+        new TestRepository<>(repoManager.openRepository(Project.nameKey(repoName)))) {
+      // Add a new file so the patch set is not a trivial rebase, to avoid default
+      // Code-Review label copying.
+      int n = c.currentPatchSetId().get() + 1;
+      RevCommit commit =
+          repo.parseBody(
+              repo.commit()
+                  .message(message.orElse("updated message"))
+                  .add("file" + n, "contents " + n)
+                  .create());
 
-    PatchSetInserter inserter =
-        patchSetFactory
-            .create(changeNotesFactory.createChecked(c), PatchSet.id(c.getId(), n), commit)
-            .setFireRevisionCreated(false)
-            .setValidate(false);
-    try (BatchUpdate bu = updateFactory.create(c.getProject(), user, TimeUtil.now());
-        ObjectInserter oi = repo.getRepository().newObjectInserter();
-        ObjectReader reader = oi.newReader();
-        RevWalk rw = new RevWalk(reader)) {
-      bu.setRepository(repo.getRepository(), rw, oi);
-      bu.setNotify(NotifyResolver.Result.none());
-      bu.addOp(c.getId(), inserter);
-      bu.execute();
+      PatchSetInserter inserter =
+          patchSetFactory
+              .create(changeNotesFactory.createChecked(c), PatchSet.id(c.getId(), n), commit)
+              .setFireRevisionCreated(false)
+              .setValidate(false);
+      try (BatchUpdate bu = updateFactory.create(c.getProject(), user, TimeUtil.now());
+          ObjectInserter oi = repo.getRepository().newObjectInserter();
+          ObjectReader reader = oi.newReader();
+          RevWalk rw = new RevWalk(reader)) {
+        bu.setRepository(repo.getRepository(), rw, oi);
+        bu.setNotify(NotifyResolver.Result.none());
+        bu.addOp(c.getId(), inserter);
+        bu.execute();
+      }
+
+      return inserter.getChange();
     }
-
-    return inserter.getChange();
   }
 
   protected ThrowableSubject assertThatQueryException(Object query) throws Exception {
@@ -4192,17 +4250,27 @@
     }
   }
 
-  protected TestRepository<Repo> createProject(String name) throws Exception {
-    gApi.projects().create(name).get();
+  @CanIgnoreReturnValue
+  protected TestRepository<Repository> createAndOpenProject(String name) throws Exception {
+    createProject(name);
     return new TestRepository<>(repoManager.openRepository(Project.nameKey(name)));
   }
 
-  protected TestRepository<Repo> createProject(String name, String parent) throws Exception {
+  protected TestRepository<Repository> createAndOpenProject(String name, String parent)
+      throws Exception {
+    createProject(name, parent);
+    return new TestRepository<>(repoManager.openRepository(Project.nameKey(name)));
+  }
+
+  protected void createProject(String name) throws Exception {
+    gApi.projects().create(name).get();
+  }
+
+  protected void createProject(String name, String parent) throws Exception {
     ProjectInput input = new ProjectInput();
     input.name = name;
     input.parent = parent;
     gApi.projects().create(input).get();
-    return new TestRepository<>(repoManager.openRepository(Project.nameKey(name)));
   }
 
   protected QueryRequest newQuery(Object query) {
diff --git a/javatests/com/google/gerrit/server/query/change/FakeQueryChangesTest.java b/javatests/com/google/gerrit/server/query/change/FakeQueryChangesTest.java
index fe60119..6b17bb6 100644
--- a/javatests/com/google/gerrit/server/query/change/FakeQueryChangesTest.java
+++ b/javatests/com/google/gerrit/server/query/change/FakeQueryChangesTest.java
@@ -27,14 +27,13 @@
 import com.google.gerrit.server.config.AllProjectsName;
 import com.google.gerrit.server.index.change.ChangeIndexCollection;
 import com.google.gerrit.testing.InMemoryModule;
-import com.google.gerrit.testing.InMemoryRepositoryManager;
-import com.google.gerrit.testing.InMemoryRepositoryManager.Repo;
 import com.google.inject.Guice;
 import com.google.inject.Inject;
 import com.google.inject.Injector;
 import java.util.List;
 import org.eclipse.jgit.junit.TestRepository;
 import org.eclipse.jgit.lib.Config;
+import org.eclipse.jgit.lib.Repository;
 import org.junit.Test;
 
 /**
@@ -58,19 +57,21 @@
   @UseClockStep
   public void stopQueryIfNoMoreResults() throws Exception {
     // create 2 visible changes
-    TestRepository<InMemoryRepositoryManager.Repo> testRepo = createProject("repo");
-    insert(testRepo, newChange(testRepo));
-    insert(testRepo, newChange(testRepo));
+    try (TestRepository<Repository> testRepo = createAndOpenProject("repo")) {
+      insert("repo", newChange(testRepo));
+      insert("repo", newChange(testRepo));
+    }
 
     // create 2 invisible changes
-    TestRepository<Repo> hiddenProject = createProject("hiddenProject");
-    insert(hiddenProject, newChange(hiddenProject));
-    insert(hiddenProject, newChange(hiddenProject));
-    projectOperations
-        .project(Project.nameKey("hiddenProject"))
-        .forUpdate()
-        .add(block(Permission.READ).ref("refs/*").group(REGISTERED_USERS))
-        .update();
+    try (TestRepository<Repository> hiddenProject = createAndOpenProject("hiddenProject")) {
+      insert("hiddenProject", newChange(hiddenProject));
+      insert("hiddenProject", newChange(hiddenProject));
+      projectOperations
+          .project(Project.nameKey("hiddenProject"))
+          .forUpdate()
+          .add(block(Permission.READ).ref("refs/*").group(REGISTERED_USERS))
+          .update();
+    }
 
     AbstractFakeIndex<?, ?, ?> idx =
         (AbstractFakeIndex<?, ?, ?>) changeIndexCollection.getSearchIndex();
@@ -83,12 +84,13 @@
   @Test
   @UseClockStep
   public void noLimitQueryPaginates() throws Exception {
-    TestRepository<InMemoryRepositoryManager.Repo> testRepo = createProject("repo");
-    // create 4 changes
-    insert(testRepo, newChange(testRepo));
-    insert(testRepo, newChange(testRepo));
-    insert(testRepo, newChange(testRepo));
-    insert(testRepo, newChange(testRepo));
+    try (TestRepository<Repository> testRepo = createAndOpenProject("repo")) {
+      // create 4 changes
+      insert("repo", newChange(testRepo));
+      insert("repo", newChange(testRepo));
+      insert("repo", newChange(testRepo));
+      insert("repo", newChange(testRepo));
+    }
 
     // Set queryLimit to 2
     projectOperations
@@ -111,11 +113,12 @@
   @UseClockStep
   public void internalQueriesPaginate() throws Exception {
     // create 4 changes
-    TestRepository<InMemoryRepositoryManager.Repo> testRepo = createProject("repo");
-    insert(testRepo, newChange(testRepo));
-    insert(testRepo, newChange(testRepo));
-    insert(testRepo, newChange(testRepo));
-    insert(testRepo, newChange(testRepo));
+    try (TestRepository<Repository> testRepo = createAndOpenProject("repo")) {
+      insert("repo", newChange(testRepo));
+      insert("repo", newChange(testRepo));
+      insert("repo", newChange(testRepo));
+      insert("repo", newChange(testRepo));
+    }
 
     // Set queryLimit to 2
     projectOperations
diff --git a/javatests/com/google/gerrit/server/query/change/LuceneQueryChangesTest.java b/javatests/com/google/gerrit/server/query/change/LuceneQueryChangesTest.java
index 9717bfb..5cae012 100644
--- a/javatests/com/google/gerrit/server/query/change/LuceneQueryChangesTest.java
+++ b/javatests/com/google/gerrit/server/query/change/LuceneQueryChangesTest.java
@@ -24,11 +24,9 @@
 import com.google.gerrit.extensions.restapi.BadRequestException;
 import com.google.gerrit.server.config.AllProjectsName;
 import com.google.gerrit.testing.InMemoryModule;
-import com.google.gerrit.testing.InMemoryRepositoryManager.Repo;
 import com.google.inject.Guice;
 import com.google.inject.Inject;
 import com.google.inject.Injector;
-import org.eclipse.jgit.junit.TestRepository;
 import org.eclipse.jgit.lib.Config;
 import org.eclipse.jgit.revwalk.RevCommit;
 import org.junit.Test;
@@ -45,11 +43,11 @@
 
   @Test
   public void fullTextWithSpecialChars() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
     RevCommit commit1 = repo.parseBody(repo.commit().message("foo_bar_foo").create());
-    Change change1 = insert(repo, newChangeForCommit(repo, commit1));
+    Change change1 = insert("repo", newChangeForCommit(repo, commit1));
     RevCommit commit2 = repo.parseBody(repo.commit().message("one.two.three").create());
-    Change change2 = insert(repo, newChangeForCommit(repo, commit2));
+    Change change2 = insert("repo", newChangeForCommit(repo, commit2));
 
     assertQuery("message:foo_ba");
     assertQuery("message:bar", change1);
@@ -63,8 +61,8 @@
   @Test
   @Override
   public void byOwnerInvalidQuery() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
-    Change change1 = insert(repo, newChange(repo), userId);
+    repo = createAndOpenProject("repo");
+    Change change1 = insert("repo", newChange(repo), userId);
     String nameEmail = user.asIdentifiedUser().getNameEmail();
 
     BadRequestException thrown =
@@ -76,17 +74,17 @@
 
   @Test
   public void openAndClosedChanges() throws Exception {
-    TestRepository<Repo> repo = createProject("repo");
+    repo = createAndOpenProject("repo");
 
     // create 3 closed changes
-    Change change1 = insert(repo, newChangeWithStatus(repo, Change.Status.MERGED));
-    Change change2 = insert(repo, newChangeWithStatus(repo, Change.Status.MERGED));
-    Change change3 = insert(repo, newChangeWithStatus(repo, Change.Status.MERGED));
+    Change change1 = insert("repo", newChangeWithStatus(repo, Change.Status.MERGED));
+    Change change2 = insert("repo", newChangeWithStatus(repo, Change.Status.MERGED));
+    Change change3 = insert("repo", newChangeWithStatus(repo, Change.Status.MERGED));
 
     // create 3 new changes
-    Change change4 = insert(repo, newChangeWithStatus(repo, Change.Status.NEW));
-    Change change5 = insert(repo, newChangeWithStatus(repo, Change.Status.NEW));
-    Change change6 = insert(repo, newChangeWithStatus(repo, Change.Status.NEW));
+    Change change4 = insert("repo", newChangeWithStatus(repo, Change.Status.NEW));
+    Change change5 = insert("repo", newChangeWithStatus(repo, Change.Status.NEW));
+    Change change6 = insert("repo", newChangeWithStatus(repo, Change.Status.NEW));
 
     // Set queryLimit to 1
     projectOperations
diff --git a/polygerrit-ui/app/elements/shared/gr-formatted-text/gr-formatted-text.ts b/polygerrit-ui/app/elements/shared/gr-formatted-text/gr-formatted-text.ts
index c8663e6..627ea27 100644
--- a/polygerrit-ui/app/elements/shared/gr-formatted-text/gr-formatted-text.ts
+++ b/polygerrit-ui/app/elements/shared/gr-formatted-text/gr-formatted-text.ts
@@ -198,7 +198,16 @@
     text = htmlEscape(text).toString();
     // Unescape block quotes '>'. This is slightly dangerous as '>' can be used
     // in HTML fragments, but it is insufficient on it's own.
-    text = text.replace(/(^|\n)&gt;/g, '$1>');
+    for (;;) {
+      const newText = text.replace(
+        /(^|\n)((?:\s{0,3}&gt;)*\s{0,3})&gt;/g,
+        '$1$2>'
+      );
+      if (newText === text) {
+        break;
+      }
+      text = newText;
+    }
 
     return text;
   }
diff --git a/polygerrit-ui/app/elements/shared/gr-formatted-text/gr-formatted-text_test.ts b/polygerrit-ui/app/elements/shared/gr-formatted-text/gr-formatted-text_test.ts
index 9acca0f..3881c62 100644
--- a/polygerrit-ui/app/elements/shared/gr-formatted-text/gr-formatted-text_test.ts
+++ b/polygerrit-ui/app/elements/shared/gr-formatted-text/gr-formatted-text_test.ts
@@ -593,5 +593,27 @@
         `
       );
     });
+
+    test('renders nested block quotes', async () => {
+      element.content = '> > > block quote';
+      await element.updateComplete;
+
+      assert.shadowDom.equal(
+        element,
+        /* HTML */ `
+          <marked-element>
+            <div slot="markdown-html" class="markdown-html">
+              <blockquote>
+                <blockquote>
+                  <blockquote>
+                    <p>block quote</p>
+                  </blockquote>
+                </blockquote>
+              </blockquote>
+            </div>
+          </marked-element>
+        `
+      );
+    });
   });
 });
diff --git a/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-section.ts b/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-section.ts
index 1c09372..28e83ae 100644
--- a/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-section.ts
+++ b/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-section.ts
@@ -16,7 +16,11 @@
   DiffPreferencesInfo,
 } from '../../../api/diff';
 import {GrDiffGroup, GrDiffGroupType} from '../gr-diff/gr-diff-group';
-import {countLines, diffClasses} from '../gr-diff/gr-diff-utils';
+import {
+  countLines,
+  diffClasses,
+  getResponsiveMode,
+} from '../gr-diff/gr-diff-utils';
 import {GrDiffRow} from './gr-diff-row';
 import '../gr-context-controls/gr-context-controls-section';
 import '../gr-context-controls/gr-context-controls';
@@ -71,6 +75,7 @@
     if (this.group.ignoredWhitespaceOnly) extras.push('ignoredWhitespaceOnly');
 
     const pairs = this.getLinePairs();
+    const responsiveMode = getResponsiveMode(this.diffPrefs, this.renderPrefs);
     const body = html`
       <tbody class=${diffClasses(...extras)}>
         ${this.renderContextControls()} ${this.renderMoveControls()}
@@ -86,6 +91,7 @@
               .lineLength=${this.diffPrefs?.line_length ?? 80}
               .tabSize=${this.diffPrefs?.tab_size ?? 2}
               .unifiedDiff=${this.isUnifiedDiff()}
+              .responsiveMode=${responsiveMode}
             >
             </gr-diff-row>
           `;
diff --git a/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-text.ts b/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-text.ts
index f7cc7e5..c1b13ac 100644
--- a/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-text.ts
+++ b/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-text.ts
@@ -115,7 +115,7 @@
     }
     const piece = html`<span
       class=${diffClasses('tab')}
-      style=${styleMap({'tab-size': `${this.tabSize}`})}
+      style=${styleMap({'tab-size': `${tabSize}`})}
       >${TAB}</span
     >`;
     this.pieces.push(piece);
diff --git a/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-text_test.ts b/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-text_test.ts
index 8f0503a..a0e7840 100644
--- a/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-text_test.ts
+++ b/polygerrit-ui/app/embed/diff/gr-diff-builder/gr-diff-text_test.ts
@@ -75,18 +75,25 @@
 
     test('tab wrapper style', async () => {
       element.lineLimit = 100;
-      element.text = '\t';
-      await element.updateComplete;
-      for (const size of [1, 3, 8, 55]) {
-        element.tabSize = size;
-        await element.updateComplete;
-        await check(
-          '\t',
-          /* HTML */ `
-            <span class="gr-diff tab" style="tab-size: ${size};"> </span>
-          `
-        );
-      }
+      element.tabSize = 4;
+      await check(
+        '\t',
+        /* HTML */ '<span class="gr-diff tab" style="tab-size:4;"></span>'
+      );
+      await check(
+        'abc\t',
+        /* HTML */ 'abc<span class="gr-diff tab" style="tab-size:1;"></span>'
+      );
+
+      element.tabSize = 8;
+      await check(
+        '\t',
+        /* HTML */ '<span class="gr-diff tab" style="tab-size:8;"></span>'
+      );
+      await check(
+        'abc\t',
+        /* HTML */ 'abc<span class="gr-diff tab" style="tab-size:5;"></span>'
+      );
     });
 
     test('tab wrapper insertion', async () => {
diff --git a/polygerrit-ui/app/embed/diff/gr-diff/gr-diff-utils.ts b/polygerrit-ui/app/embed/diff/gr-diff/gr-diff-utils.ts
index f583c2e..3392951 100644
--- a/polygerrit-ui/app/embed/diff/gr-diff/gr-diff-utils.ts
+++ b/polygerrit-ui/app/embed/diff/gr-diff/gr-diff-utils.ts
@@ -49,14 +49,14 @@
 }
 
 export function getResponsiveMode(
-  prefs: DiffPreferencesInfo,
+  prefs?: DiffPreferencesInfo,
   renderPrefs?: RenderPreferences
 ): DiffResponsiveMode {
   if (renderPrefs?.responsive_mode) {
     return renderPrefs.responsive_mode;
   }
   // Backwards compatibility to the line_wrapping param.
-  if (prefs.line_wrapping) {
+  if (prefs?.line_wrapping) {
     return 'FULL_RESPONSIVE';
   }
   return 'NONE';