Remove remnants of JUnit 4 rules (#1336)

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core/src/main/java/google/registry/backup/AppEngineEnvironment.java

@@ -48,7 +48,7 @@ public class AppEngineEnvironment implements Closeable {
 
   public AppEngineEnvironment(String appId) {
     isPlaceHolderNeeded = ApiProxy.getCurrentEnvironment() == null;
-    // isPlaceHolderNeeded may be true when we are invoked in a test with AppEngineRule.
+    // isPlaceHolderNeeded may be true when we are invoked in a test with AppEngineExtension.
     if (isPlaceHolderNeeded) {
       ApiProxy.setEnvironmentForCurrentThread(createAppEngineEnvironment(appId));
     }

core/src/main/java/google/registry/persistence/transaction/DummyJpaTransactionManager.java

@@ -20,11 +20,11 @@ import java.lang.reflect.Proxy;
  * A dummy implementation for {@link JpaTransactionManager} which throws exception when any of its
  * method is invoked.
  *
- * <p>This is used to initialize the {@link TransactionManagerFactory#jpaTm} when running unit
+ * <p>This is used to initialize the {@link TransactionManagerFactory#jpaTm()} when running unit
  * tests, because obviously we cannot connect to the actual Cloud SQL backend in a unit test.
  *
- * <p>If a unit test needs to access the Cloud SQL database, it must add JpaTransactionManagerRule
+ * <p>If a unit test needs to access the Cloud SQL database, it must add {@code
- * as a JUnit rule in the test class.
+ * JpaTransactionManagerExtension} as a JUnit extension in the test class.
  */
 public class DummyJpaTransactionManager {
 
@@ -37,7 +37,7 @@ public class DummyJpaTransactionManager {
             (proxy, method, args) -> {
               throw new UnsupportedOperationException(
                   "JpaTransactionManager was not initialized as the runtime is detected as"
-                      + " Unittest. Add JpaTransactionManagerRule in the unit test for"
+                      + " Unittest. Add JpaTransactionManagerExtension in the unit test for"
                       + " initialization.");
             });
   }

core/src/test/java/google/registry/batch/RelockDomainActionTest.java

@@ -86,7 +86,7 @@ public class RelockDomainActionTest {
               mock(AppEngineServiceUtils.class), clock, Duration.ZERO));
 
   @RegisterExtension
-  public final AppEngineExtension appEngineRule =
+  public final AppEngineExtension appEngineExtension =
       AppEngineExtension.builder()
           .withDatastoreAndCloudSql()
           .withTaskQueue()

core/src/test/java/google/registry/beam/common/RegistryJpaReadTest.java

@@ -40,8 +40,8 @@ import google.registry.model.registrar.Registrar;
 import google.registry.model.tld.Registry;
 import google.registry.model.transfer.ContactTransferData;
 import google.registry.persistence.transaction.CriteriaQueryBuilder;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaIntegrationTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaIntegrationTestExtension;
 import google.registry.testing.AppEngineExtension;
 import google.registry.testing.DatabaseHelper;
 import google.registry.testing.DatastoreEntityExtension;
@@ -67,7 +67,7 @@ public class RegistryJpaReadTest {
 
   @RegisterExtension
   final transient JpaIntegrationTestExtension database =
-      new JpaTestRules.Builder().withClock(fakeClock).buildIntegrationTestRule();
+      new JpaTestExtensions.Builder().withClock(fakeClock).buildIntegrationTestExtension();
 
   @RegisterExtension
   final transient TestPipelineExtension testPipeline =

core/src/test/java/google/registry/beam/common/RegistryJpaWriteTest.java

@@ -29,8 +29,8 @@ import google.registry.model.ImmutableObject;
 import google.registry.model.contact.ContactResource;
 import google.registry.model.ofy.Ofy;
 import google.registry.model.registrar.Registrar;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaIntegrationTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaIntegrationTestExtension;
 import google.registry.testing.AppEngineExtension;
 import google.registry.testing.DatabaseHelper;
 import google.registry.testing.DatastoreEntityExtension;
@@ -56,11 +56,11 @@ class RegistryJpaWriteTest implements Serializable {
   @Order(Order.DEFAULT - 1)
   final transient DatastoreEntityExtension datastore = new DatastoreEntityExtension();
 
-  @RegisterExtension final transient InjectExtension injectRule = new InjectExtension();
+  @RegisterExtension final transient InjectExtension injectExtension = new InjectExtension();
 
   @RegisterExtension
   final transient JpaIntegrationTestExtension database =
-      new JpaTestRules.Builder().withClock(fakeClock).buildIntegrationTestRule();
+      new JpaTestExtensions.Builder().withClock(fakeClock).buildIntegrationTestExtension();
 
   @RegisterExtension
   final transient TestPipelineExtension testPipeline =
@@ -71,7 +71,7 @@ class RegistryJpaWriteTest implements Serializable {
   @BeforeEach
   void beforeEach() throws Exception {
     try (BackupTestStore store = new BackupTestStore(fakeClock)) {
-      injectRule.setStaticField(Ofy.class, "clock", fakeClock);
+      injectExtension.setStaticField(Ofy.class, "clock", fakeClock);
 
       // Required for contacts created below.
       Registrar ofyRegistrar = AppEngineExtension.makeRegistrar2();

core/src/test/java/google/registry/beam/initsql/BackupTestStoreTest.java

@@ -34,8 +34,8 @@ import google.registry.model.domain.DomainBase;
 import google.registry.model.ofy.Ofy;
 import google.registry.model.tld.Registry;
 import google.registry.persistence.VKey;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaIntegrationTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaIntegrationTestExtension;
 import google.registry.testing.DatastoreEntityExtension;
 import google.registry.testing.FakeClock;
 import google.registry.testing.InjectExtension;
@@ -62,14 +62,14 @@ public class BackupTestStoreTest {
 
   @RegisterExtension
   final transient JpaIntegrationTestExtension jpaIntegrationTestExtension =
-      new JpaTestRules.Builder().buildIntegrationTestRule();
+      new JpaTestExtensions.Builder().buildIntegrationTestExtension();
 
   @RegisterExtension
   @Order(value = 1)
   final transient DatastoreEntityExtension datastoreEntityExtension =
       new DatastoreEntityExtension();
 
-  @RegisterExtension InjectExtension injectRule = new InjectExtension();
+  @RegisterExtension InjectExtension injectExtension = new InjectExtension();
 
   private FakeClock fakeClock;
   private BackupTestStore store;
@@ -83,7 +83,7 @@ public class BackupTestStoreTest {
   void beforeEach() throws Exception {
     fakeClock = new FakeClock(START_TIME);
     store = new BackupTestStore(fakeClock);
-    injectRule.setStaticField(Ofy.class, "clock", fakeClock);
+    injectExtension.setStaticField(Ofy.class, "clock", fakeClock);
 
     registry = newRegistry("tld1", "TLD1");
     store.insertOrUpdate(registry);

core/src/test/java/google/registry/beam/initsql/CommitLogTransformsTest.java

@@ -26,8 +26,8 @@ import google.registry.model.contact.ContactResource;
 import google.registry.model.domain.DomainBase;
 import google.registry.model.ofy.Ofy;
 import google.registry.model.tld.Registry;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaIntegrationTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaIntegrationTestExtension;
 import google.registry.testing.DatastoreEntityExtension;
 import google.registry.testing.FakeClock;
 import google.registry.testing.InjectExtension;
@@ -62,11 +62,11 @@ class CommitLogTransformsTest implements Serializable {
   @TempDir
   transient Path tmpDir;
 
-  @RegisterExtension final transient InjectExtension injectRule = new InjectExtension();
+  @RegisterExtension final transient InjectExtension injectExtension = new InjectExtension();
 
   @RegisterExtension
   final transient JpaIntegrationTestExtension jpaIntegrationTestExtension =
-      new JpaTestRules.Builder().withClock(fakeClock).buildIntegrationTestRule();
+      new JpaTestExtensions.Builder().withClock(fakeClock).buildIntegrationTestExtension();
 
   @RegisterExtension
   @Order(value = 1)
@@ -89,7 +89,7 @@ class CommitLogTransformsTest implements Serializable {
   @BeforeEach
   void beforeEach() throws Exception {
     store = new BackupTestStore(fakeClock);
-    injectRule.setStaticField(Ofy.class, "clock", fakeClock);
+    injectExtension.setStaticField(Ofy.class, "clock", fakeClock);
 
     registry = newRegistry("tld1", "TLD1");
     store.insertOrUpdate(registry);

core/src/test/java/google/registry/beam/initsql/DomainBaseUtilTest.java

@@ -68,14 +68,14 @@ public class DomainBaseUtilTest {
   private Key<DomainBase> domainKey;
 
   @RegisterExtension
-  AppEngineExtension appEngineRule =
+  AppEngineExtension appEngineExtension =
       AppEngineExtension.builder().withDatastoreAndCloudSql().withClock(fakeClock).build();
 
-  @RegisterExtension InjectExtension injectRule = new InjectExtension();
+  @RegisterExtension InjectExtension injectExtension = new InjectExtension();
 
   @BeforeEach
   void beforeEach() {
-    injectRule.setStaticField(Ofy.class, "clock", fakeClock);
+    injectExtension.setStaticField(Ofy.class, "clock", fakeClock);
     createTld("com");
     domainKey = Key.create(null, DomainBase.class, "4-COM");
     VKey<HostResource> hostKey =

core/src/test/java/google/registry/beam/initsql/ExportLoadingTransformsTest.java

@@ -27,8 +27,8 @@ import google.registry.model.contact.ContactResource;
 import google.registry.model.domain.DomainBase;
 import google.registry.model.ofy.Ofy;
 import google.registry.model.tld.Registry;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaIntegrationTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaIntegrationTestExtension;
 import google.registry.testing.DatastoreEntityExtension;
 import google.registry.testing.FakeClock;
 import google.registry.testing.InjectExtension;
@@ -70,11 +70,11 @@ class ExportLoadingTransformsTest implements Serializable {
   @TempDir
   transient Path tmpDir;
 
-  @RegisterExtension final transient InjectExtension injectRule = new InjectExtension();
+  @RegisterExtension final transient InjectExtension injectExtension = new InjectExtension();
 
   @RegisterExtension
   final transient JpaIntegrationTestExtension jpaIntegrationTestExtension =
-      new JpaTestRules.Builder().buildIntegrationTestRule();
+      new JpaTestExtensions.Builder().buildIntegrationTestExtension();
 
   @RegisterExtension
   @Order(value = 1)
@@ -98,7 +98,7 @@ class ExportLoadingTransformsTest implements Serializable {
   void beforeEach() throws Exception {
     fakeClock = new FakeClock(START_TIME);
     store = new BackupTestStore(fakeClock);
-    injectRule.setStaticField(Ofy.class, "clock", fakeClock);
+    injectExtension.setStaticField(Ofy.class, "clock", fakeClock);
 
     registry = newRegistry("tld1", "TLD1");
     store.insertOrUpdate(registry);

core/src/test/java/google/registry/beam/initsql/InitSqlPipelineTest.java

@@ -60,8 +60,8 @@ import google.registry.model.tld.Registry;
 import google.registry.model.transfer.DomainTransferData;
 import google.registry.model.transfer.TransferStatus;
 import google.registry.persistence.VKey;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaIntegrationTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaIntegrationTestExtension;
 import google.registry.testing.AppEngineExtension;
 import google.registry.testing.DatastoreEntityExtension;
 import google.registry.testing.FakeClock;
@@ -108,7 +108,7 @@ class InitSqlPipelineTest {
   @Order(Order.DEFAULT - 1)
   final transient DatastoreEntityExtension datastore = new DatastoreEntityExtension();
 
-  @RegisterExtension final transient InjectExtension injectRule = new InjectExtension();
+  @RegisterExtension final transient InjectExtension injectExtension = new InjectExtension();
 
   @SuppressWarnings("WeakerAccess")
   @TempDir
@@ -120,7 +120,7 @@ class InitSqlPipelineTest {
 
   @RegisterExtension
   final transient JpaIntegrationTestExtension database =
-      new JpaTestRules.Builder().withClock(fakeClock).buildIntegrationTestRule();
+      new JpaTestExtensions.Builder().withClock(fakeClock).buildIntegrationTestExtension();
 
   private File exportRootDir;
   private File exportDir;
@@ -141,7 +141,7 @@ class InitSqlPipelineTest {
   @BeforeEach
   void beforeEach() throws Exception {
     try (BackupTestStore store = new BackupTestStore(fakeClock)) {
-      injectRule.setStaticField(Ofy.class, "clock", fakeClock);
+      injectExtension.setStaticField(Ofy.class, "clock", fakeClock);
       exportRootDir = Files.createDirectory(tmpDir.resolve("exports")).toFile();
 
       persistResource(newRegistry("com", "COM"));

core/src/test/java/google/registry/beam/initsql/LoadDatastoreSnapshotTest.java

@@ -29,8 +29,8 @@ import google.registry.model.domain.DomainBase;
 import google.registry.model.eppcommon.AuthInfo.PasswordAuth;
 import google.registry.model.ofy.Ofy;
 import google.registry.model.tld.Registry;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaIntegrationTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaIntegrationTestExtension;
 import google.registry.testing.DatastoreEntityExtension;
 import google.registry.testing.FakeClock;
 import google.registry.testing.InjectExtension;
@@ -86,11 +86,11 @@ class LoadDatastoreSnapshotTest {
   @TempDir
   transient Path tmpDir;
 
-  @RegisterExtension final transient InjectExtension injectRule = new InjectExtension();
+  @RegisterExtension final transient InjectExtension injectExtension = new InjectExtension();
 
   @RegisterExtension
   final transient JpaIntegrationTestExtension jpaIntegrationTestExtension =
-      new JpaTestRules.Builder().buildIntegrationTestRule();
+      new JpaTestExtensions.Builder().buildIntegrationTestExtension();
 
   @RegisterExtension
   @Order(value = 1)
@@ -119,7 +119,7 @@ class LoadDatastoreSnapshotTest {
   void beforeEach() throws Exception {
     fakeClock = new FakeClock(START_TIME);
     try (BackupTestStore store = new BackupTestStore(fakeClock)) {
-      injectRule.setStaticField(Ofy.class, "clock", fakeClock);
+      injectExtension.setStaticField(Ofy.class, "clock", fakeClock);
 
       exportRootDir = Files.createDirectory(tmpDir.resolve("export_root")).toFile();
       commitLogsDir = Files.createDirectory(tmpDir.resolve("commit_logs")).toFile();

core/src/test/java/google/registry/beam/invoicing/InvoicingPipelineTest.java

@@ -43,8 +43,8 @@ import google.registry.model.domain.DomainHistory;
 import google.registry.model.registrar.Registrar;
 import google.registry.model.reporting.HistoryEntry;
 import google.registry.model.tld.Registry;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaIntegrationTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaIntegrationTestExtension;
 import google.registry.testing.DatastoreEntityExtension;
 import google.registry.testing.FakeClock;
 import google.registry.testing.TestDataHelper;
@@ -235,7 +235,7 @@ class InvoicingPipelineTest {
 
   @RegisterExtension
   final JpaIntegrationTestExtension database =
-      new JpaTestRules.Builder().withClock(new FakeClock()).buildIntegrationTestRule();
+      new JpaTestExtensions.Builder().withClock(new FakeClock()).buildIntegrationTestExtension();
 
   @TempDir Path tmpDir;
 

core/src/test/java/google/registry/beam/rde/RdePipelineTest.java

@@ -62,8 +62,8 @@ import google.registry.model.registrar.Registrar;
 import google.registry.model.registrar.Registrar.State;
 import google.registry.model.tld.Registry;
 import google.registry.persistence.VKey;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaIntegrationTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaIntegrationTestExtension;
 import google.registry.persistence.transaction.TransactionManagerFactory;
 import google.registry.rde.DepositFragment;
 import google.registry.rde.Ghostryde;
@@ -150,7 +150,7 @@ public class RdePipelineTest {
 
   @RegisterExtension
   final JpaIntegrationTestExtension database =
-      new JpaTestRules.Builder().withClock(clock).buildIntegrationTestRule();
+      new JpaTestExtensions.Builder().withClock(clock).buildIntegrationTestExtension();
 
   @RegisterExtension
   final TestPipelineExtension pipeline =

core/src/test/java/google/registry/beam/spec11/Spec11PipelineTest.java

@@ -47,8 +47,8 @@ import google.registry.model.registrar.Registrar;
 import google.registry.model.reporting.Spec11ThreatMatch;
 import google.registry.model.reporting.Spec11ThreatMatch.ThreatType;
 import google.registry.model.reporting.Spec11ThreatMatchDao;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaIntegrationTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaIntegrationTestExtension;
 import google.registry.testing.DatastoreEntityExtension;
 import google.registry.testing.FakeClock;
 import google.registry.testing.FakeSleeper;
@@ -126,7 +126,7 @@ class Spec11PipelineTest {
 
   @RegisterExtension
   final JpaIntegrationTestExtension database =
-      new JpaTestRules.Builder().withClock(new FakeClock()).buildIntegrationTestRule();
+      new JpaTestExtensions.Builder().withClock(new FakeClock()).buildIntegrationTestExtension();
 
   private final Spec11PipelineOptions options =
       PipelineOptionsFactory.create().as(Spec11PipelineOptions.class);

core/src/test/java/google/registry/cron/CommitLogFanoutActionTest.java

@@ -36,7 +36,7 @@ class CommitLogFanoutActionTest {
   private static final String QUEUE = "the-queue";
 
   @RegisterExtension
-  final AppEngineExtension appEngineRule =
+  final AppEngineExtension appEngineExtension =
       AppEngineExtension.builder()
           .withDatastoreAndCloudSql()
           .withTaskQueue(

core/src/test/java/google/registry/export/sheet/SyncRegistrarsSheetTest.java

@@ -81,7 +81,7 @@ public class SyncRegistrarsSheetTest {
   void beforeEach() {
     inject.setStaticField(Ofy.class, "clock", clock);
     createTld("example");
-    // Remove Registrar entities created by AppEngineRule (and RegistrarContact's, for jpa).
+    // Remove Registrar entities created by AppEngineExtension (and RegistrarContact's, for jpa).
     // We don't do this for ofy because ofy's loadAllOf() can't be called in a transaction but
     // _must_ be called in a transaction in JPA.
     if (!tm().isOfy()) {

core/src/test/java/google/registry/flows/EppControllerTest.java

@@ -67,7 +67,7 @@ import org.mockito.quality.Strictness;
 class EppControllerTest {
 
   @RegisterExtension
-  AppEngineExtension appEngineRule =
+  AppEngineExtension appEngineExtension =
       new AppEngineExtension.Builder().withDatastoreAndCloudSql().build();
 
   @Mock SessionMetadata sessionMetadata;

core/src/test/java/google/registry/flows/FlowRunnerTest.java

@@ -51,7 +51,7 @@ import org.mockito.Mockito;
 class FlowRunnerTest {
 
   @RegisterExtension
-  final AppEngineExtension appEngineRule =
+  final AppEngineExtension appEngineExtension =
       new AppEngineExtension.Builder().withDatastoreAndCloudSql().build();
 
   private final FlowRunner flowRunner = new FlowRunner();

core/src/test/java/google/registry/model/ModelUtilsTest.java

@@ -29,7 +29,7 @@ import org.junit.jupiter.api.extension.RegisterExtension;
 public class ModelUtilsTest {
 
   @RegisterExtension
-  public AppEngineExtension appEngineRule = new AppEngineExtension.Builder().build();
+  public AppEngineExtension appEngineExtension = new AppEngineExtension.Builder().build();
 
   /** Test class for reflection methods. */
   public static class TestClass extends ImmutableObject implements Buildable {

core/src/test/java/google/registry/model/ofy/CommitLogMutationTest.java

@@ -46,7 +46,7 @@ public class CommitLogMutationTest {
 
   @BeforeEach
   void before() {
-    // Initialize this late to avoid dependency on NamespaceManager prior to AppEngineRule.
+    // Initialize this late to avoid dependency on NamespaceManager prior to AppEngineExtension.
     manifestKey = CommitLogManifest.createKey(CommitLogBucket.getBucketKey(1), NOW);
     createTld("tld");
     someObject = Registry.get("tld");

core/src/test/java/google/registry/model/ofy/OfyFilterTest.java

@@ -38,7 +38,7 @@ class OfyFilterTest {
   private LocalServiceTestHelper helper;
   private ObjectifyFactory factory;
 
-  // We can't use AppEngineRule, because it triggers the precise behavior that we are testing.
+  // We can't use AppEngineExtension, because it triggers the precise behavior that we are testing.
 
   @BeforeEach
   void beforeEach() {

core/src/test/java/google/registry/model/ofy/OfyTest.java

@@ -83,7 +83,7 @@ public class OfyTest {
             .setTrid(Trid.create("client", "server"))
             .setXmlBytes("<xml></xml>".getBytes(UTF_8))
             .build();
-    // This can't be initialized earlier because namespaces need the AppEngineRule to work.
+    // This can't be initialized earlier because namespaces need the AppEngineExtension to work.
   }
 
   private void doBackupGroupRootTimestampInversionTest(Runnable runnable) {

core/src/test/java/google/registry/model/tld/label/ReservedListDaoTest.java

@@ -19,8 +19,8 @@ import static google.registry.persistence.transaction.TransactionManagerFactory.
 
 import com.google.common.collect.ImmutableMap;
 import google.registry.model.tld.label.ReservedList.ReservedListEntry;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaIntegrationWithCoverageExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaIntegrationWithCoverageExtension;
 import google.registry.testing.DatastoreEntityExtension;
 import google.registry.testing.FakeClock;
 import org.junit.jupiter.api.BeforeEach;
@@ -39,7 +39,7 @@ public class ReservedListDaoTest {
 
   @RegisterExtension
   JpaIntegrationWithCoverageExtension jpa =
-      new JpaTestRules.Builder().withClock(fakeClock).buildIntegrationWithCoverageExtension();
+      new JpaTestExtensions.Builder().withClock(fakeClock).buildIntegrationWithCoverageExtension();
 
   private ImmutableMap<String, ReservedListEntry> testReservations;
 

core/src/test/java/google/registry/model/tmch/ClaimsListDaoTest.java

@@ -18,8 +18,8 @@ import static com.google.common.truth.Truth.assertThat;
 import static org.junit.jupiter.api.Assertions.assertThrows;
 
 import com.google.common.collect.ImmutableMap;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaIntegrationWithCoverageExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaIntegrationWithCoverageExtension;
 import google.registry.testing.FakeClock;
 import javax.persistence.PersistenceException;
 import org.junit.jupiter.api.Test;
@@ -32,7 +32,7 @@ public class ClaimsListDaoTest {
 
   @RegisterExtension
   final JpaIntegrationWithCoverageExtension jpa =
-      new JpaTestRules.Builder().withClock(fakeClock).buildIntegrationWithCoverageExtension();
+      new JpaTestExtensions.Builder().withClock(fakeClock).buildIntegrationWithCoverageExtension();
 
   @Test
   void save_insertsClaimsListSuccessfully() {

core/src/test/java/google/registry/persistence/EntityCallbacksListenerTest.java

@@ -22,8 +22,8 @@ import static google.registry.testing.DatabaseHelper.insertInDb;
 
 import com.google.common.collect.ImmutableSet;
 import google.registry.model.ImmutableObject;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaUnitTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaUnitTestExtension;
 import java.lang.reflect.Method;
 import javax.persistence.Embeddable;
 import javax.persistence.Embedded;
@@ -46,7 +46,7 @@ class EntityCallbacksListenerTest {
 
   @RegisterExtension
   public final JpaUnitTestExtension jpaExtension =
-      new JpaTestRules.Builder().withEntityClass(TestEntity.class).buildUnitTestRule();
+      new JpaTestExtensions.Builder().withEntityClass(TestEntity.class).buildUnitTestExtension();
 
   @Test
   void verifyAllCallbacks_executedExpectedTimes() {

core/src/test/java/google/registry/persistence/VKeyTest.java

@@ -33,7 +33,7 @@ import org.junit.jupiter.api.extension.RegisterExtension;
 class VKeyTest {
 
   @RegisterExtension
-  final AppEngineExtension appEngineRule =
+  final AppEngineExtension appEngineExtension =
       AppEngineExtension.builder()
           .withDatastoreAndCloudSql()
           .withOfyTestEntities(TestObject.class)

core/src/test/java/google/registry/persistence/converter/AllocationTokenStatusTransitionConverterTest.java

@@ -27,8 +27,8 @@ import google.registry.model.ImmutableObject;
 import google.registry.model.common.TimedTransitionProperty;
 import google.registry.model.domain.token.AllocationToken.TokenStatus;
 import google.registry.model.domain.token.AllocationToken.TokenStatusTransition;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaUnitTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaUnitTestExtension;
 import javax.persistence.Entity;
 import javax.persistence.Id;
 import org.joda.time.DateTime;
@@ -40,9 +40,9 @@ public class AllocationTokenStatusTransitionConverterTest {
 
   @RegisterExtension
   public final JpaUnitTestExtension jpa =
-      new JpaTestRules.Builder()
+      new JpaTestExtensions.Builder()
           .withEntityClass(AllocationTokenStatusTransitionConverterTestEntity.class)
-          .buildUnitTestRule();
+          .buildUnitTestExtension();
 
   private static final ImmutableSortedMap<DateTime, TokenStatus> values =
       ImmutableSortedMap.of(

core/src/test/java/google/registry/persistence/converter/BillingCostTransitionConverterTest.java

@@ -24,8 +24,8 @@ import com.google.common.collect.ImmutableSortedMap;
 import google.registry.model.ImmutableObject;
 import google.registry.model.common.TimedTransitionProperty;
 import google.registry.model.tld.Registry.BillingCostTransition;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaUnitTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaUnitTestExtension;
 import javax.persistence.Entity;
 import javax.persistence.Id;
 import org.joda.money.Money;
@@ -38,9 +38,7 @@ public class BillingCostTransitionConverterTest {
 
   @RegisterExtension
   public final JpaUnitTestExtension jpa =
-      new JpaTestRules.Builder()
+      new JpaTestExtensions.Builder().withEntityClass(TestEntity.class).buildUnitTestExtension();
-          .withEntityClass(TestEntity.class)
-          .buildUnitTestRule();
 
   private static final ImmutableSortedMap<DateTime, Money> values =
       ImmutableSortedMap.of(

core/src/test/java/google/registry/persistence/converter/BloomFilterConverterTest.java

@@ -23,8 +23,8 @@ import com.google.common.collect.ImmutableSet;
 import com.google.common.hash.BloomFilter;
 import google.registry.model.ImmutableObject;
 import google.registry.model.replay.EntityTest.EntityForTesting;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaUnitTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaUnitTestExtension;
 import javax.persistence.Entity;
 import javax.persistence.Id;
 import org.junit.jupiter.api.Test;
@@ -35,7 +35,7 @@ class BloomFilterConverterTest {
 
   @RegisterExtension
   public final JpaUnitTestExtension jpaExtension =
-      new JpaTestRules.Builder().withEntityClass(TestEntity.class).buildUnitTestRule();
+      new JpaTestExtensions.Builder().withEntityClass(TestEntity.class).buildUnitTestExtension();
 
   @Test
   void roundTripConversion_returnsSameBloomFilter() {

core/src/test/java/google/registry/persistence/converter/CidrAddressBlockListConverterTest.java

@@ -20,8 +20,8 @@ import static google.registry.testing.DatabaseHelper.insertInDb;
 
 import com.google.common.collect.ImmutableList;
 import google.registry.model.ImmutableObject;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaUnitTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaUnitTestExtension;
 import google.registry.util.CidrAddressBlock;
 import java.util.List;
 import javax.persistence.Entity;
@@ -34,7 +34,7 @@ public class CidrAddressBlockListConverterTest {
 
   @RegisterExtension
   public final JpaUnitTestExtension jpaExtension =
-      new JpaTestRules.Builder().withEntityClass(TestEntity.class).buildUnitTestRule();
+      new JpaTestExtensions.Builder().withEntityClass(TestEntity.class).buildUnitTestExtension();
 
   @Test
   void roundTripConversion_returnsSameCidrAddressBlock() {

core/src/test/java/google/registry/persistence/converter/CreateAutoTimestampConverterTest.java

@@ -20,8 +20,8 @@ import static google.registry.testing.DatabaseHelper.insertInDb;
 import google.registry.model.CreateAutoTimestamp;
 import google.registry.model.ImmutableObject;
 import google.registry.model.replay.EntityTest.EntityForTesting;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaUnitTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaUnitTestExtension;
 import google.registry.testing.FakeClock;
 import javax.persistence.Entity;
 import javax.persistence.Id;
@@ -36,10 +36,10 @@ public class CreateAutoTimestampConverterTest {
 
   @RegisterExtension
   public final JpaUnitTestExtension jpaExtension =
-      new JpaTestRules.Builder()
+      new JpaTestExtensions.Builder()
           .withClock(fakeClock)
           .withEntityClass(TestEntity.class)
-          .buildUnitTestRule();
+          .buildUnitTestExtension();
 
   @Test
   void testTypeConversion() {

core/src/test/java/google/registry/persistence/converter/CurrencyToBillingConverterTest.java

@@ -21,8 +21,8 @@ import static google.registry.testing.DatabaseHelper.insertInDb;
 import com.google.common.collect.ImmutableMap;
 import google.registry.model.ImmutableObject;
 import google.registry.model.registrar.Registrar.BillingAccountEntry;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaUnitTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaUnitTestExtension;
 import java.util.Map;
 import javax.persistence.Entity;
 import javax.persistence.Id;
@@ -35,9 +35,7 @@ public class CurrencyToBillingConverterTest {
 
   @RegisterExtension
   public final JpaUnitTestExtension jpaExtension =
-      new JpaTestRules.Builder()
+      new JpaTestExtensions.Builder().withEntityClass(TestEntity.class).buildUnitTestExtension();
-          .withEntityClass(TestEntity.class)
-          .buildUnitTestRule();
 
   @Test
   void roundTripConversion_returnsSameCurrencyToBillingMap() {

core/src/test/java/google/registry/persistence/converter/CurrencyUnitConverterTest.java

@@ -21,8 +21,8 @@ import static org.junit.jupiter.api.Assertions.assertThrows;
 
 import google.registry.model.ImmutableObject;
 import google.registry.model.replay.EntityTest.EntityForTesting;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaUnitTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaUnitTestExtension;
 import javax.persistence.Entity;
 import javax.persistence.Id;
 import javax.persistence.PersistenceException;
@@ -35,7 +35,7 @@ public class CurrencyUnitConverterTest {
 
   @RegisterExtension
   public final JpaUnitTestExtension jpaExtension =
-      new JpaTestRules.Builder().withEntityClass(TestEntity.class).buildUnitTestRule();
+      new JpaTestExtensions.Builder().withEntityClass(TestEntity.class).buildUnitTestExtension();
 
   @Test
   void roundTripConversion() {

core/src/test/java/google/registry/persistence/converter/DatabaseMigrationScheduleTransitionConverterTest.java

@@ -24,8 +24,8 @@ import google.registry.model.ImmutableObject;
 import google.registry.model.common.DatabaseMigrationStateSchedule.MigrationState;
 import google.registry.model.common.DatabaseMigrationStateSchedule.MigrationStateTransition;
 import google.registry.model.common.TimedTransitionProperty;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaUnitTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaUnitTestExtension;
 import javax.persistence.Entity;
 import javax.persistence.Id;
 import org.joda.time.DateTime;
@@ -37,9 +37,9 @@ public class DatabaseMigrationScheduleTransitionConverterTest {
 
   @RegisterExtension
   public final JpaUnitTestExtension jpa =
-      new JpaTestRules.Builder()
+      new JpaTestExtensions.Builder()
           .withEntityClass(DatabaseMigrationScheduleTransitionConverterTestEntity.class)
-          .buildUnitTestRule();
+          .buildUnitTestExtension();
 
   private static final ImmutableSortedMap<DateTime, MigrationState> values =
       ImmutableSortedMap.of(

core/src/test/java/google/registry/persistence/converter/DateTimeConverterTest.java

@@ -19,8 +19,8 @@ import static google.registry.persistence.transaction.TransactionManagerFactory.
 import static google.registry.testing.DatabaseHelper.insertInDb;
 
 import google.registry.model.ImmutableObject;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaUnitTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaUnitTestExtension;
 import java.sql.Timestamp;
 import javax.persistence.Entity;
 import javax.persistence.Id;
@@ -34,7 +34,7 @@ public class DateTimeConverterTest {
 
   @RegisterExtension
   public final JpaUnitTestExtension jpaExtension =
-      new JpaTestRules.Builder().withEntityClass(TestEntity.class).buildUnitTestRule();
+      new JpaTestExtensions.Builder().withEntityClass(TestEntity.class).buildUnitTestExtension();
 
   private final DateTimeConverter converter = new DateTimeConverter();
 

core/src/test/java/google/registry/persistence/converter/DurationConverterTest.java

@@ -20,8 +20,8 @@ import static google.registry.testing.DatabaseHelper.insertInDb;
 
 import google.registry.model.ImmutableObject;
 import google.registry.model.replay.EntityTest.EntityForTesting;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaUnitTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaUnitTestExtension;
 import javax.persistence.Entity;
 import javax.persistence.Id;
 import org.joda.time.Duration;
@@ -34,7 +34,9 @@ public class DurationConverterTest {
 
   @RegisterExtension
   public final JpaUnitTestExtension jpaExtension =
-      new JpaTestRules.Builder().withEntityClass(DurationTestEntity.class).buildUnitTestRule();
+      new JpaTestExtensions.Builder()
+          .withEntityClass(DurationTestEntity.class)
+          .buildUnitTestExtension();
 
   private final DurationConverter converter = new DurationConverter();
 

core/src/test/java/google/registry/persistence/converter/JodaMoneyConverterTest.java

@@ -20,8 +20,8 @@ import static google.registry.testing.DatabaseHelper.insertInDb;
 import com.google.common.collect.ImmutableMap;
 import google.registry.model.ImmutableObject;
 import google.registry.model.replay.EntityTest.EntityForTesting;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaUnitTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaUnitTestExtension;
 import java.math.BigDecimal;
 import java.util.Arrays;
 import java.util.List;
@@ -64,9 +64,9 @@ public class JodaMoneyConverterTest {
 
   @RegisterExtension
   public final JpaUnitTestExtension jpaExtension =
-      new JpaTestRules.Builder()
+      new JpaTestExtensions.Builder()
           .withEntityClass(TestEntity.class, ComplexTestEntity.class)
-          .buildUnitTestRule();
+          .buildUnitTestExtension();
 
   @Test
   void roundTripConversion() {

core/src/test/java/google/registry/persistence/converter/LocalDateConverterTest.java

@@ -21,8 +21,8 @@ import static google.registry.testing.DatabaseHelper.insertInDb;
 import google.registry.model.ImmutableObject;
 import google.registry.model.replay.EntityTest;
 import google.registry.persistence.VKey;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaUnitTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaUnitTestExtension;
 import javax.persistence.Entity;
 import javax.persistence.Id;
 import org.joda.time.LocalDate;
@@ -35,9 +35,9 @@ public class LocalDateConverterTest {
 
   @RegisterExtension
   public final JpaUnitTestExtension jpaExtension =
-      new JpaTestRules.Builder()
+      new JpaTestExtensions.Builder()
           .withEntityClass(LocalDateConverterTestEntity.class)
-          .buildUnitTestRule();
+          .buildUnitTestExtension();
 
   private final LocalDate exampleDate = LocalDate.parse("2020-06-10", ISODateTimeFormat.date());
 

core/src/test/java/google/registry/persistence/converter/StatusValueSetConverterTest.java

@@ -21,8 +21,8 @@ import static google.registry.testing.DatabaseHelper.insertInDb;
 import com.google.common.collect.ImmutableSet;
 import google.registry.model.ImmutableObject;
 import google.registry.model.eppcommon.StatusValue;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaUnitTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaUnitTestExtension;
 import java.util.Set;
 import javax.persistence.Entity;
 import javax.persistence.Id;
@@ -34,7 +34,7 @@ public class StatusValueSetConverterTest {
 
   @RegisterExtension
   public final JpaUnitTestExtension jpaExtension =
-      new JpaTestRules.Builder().withEntityClass(TestEntity.class).buildUnitTestRule();
+      new JpaTestExtensions.Builder().withEntityClass(TestEntity.class).buildUnitTestExtension();
 
   @Test
   void testRoundTrip() {

core/src/test/java/google/registry/persistence/converter/StringListConverterTest.java

@@ -21,8 +21,8 @@ import static org.junit.jupiter.api.Assertions.assertThrows;
 
 import com.google.common.collect.ImmutableList;
 import google.registry.model.ImmutableObject;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaUnitTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaUnitTestExtension;
 import java.util.List;
 import javax.persistence.Entity;
 import javax.persistence.Id;
@@ -35,7 +35,7 @@ public class StringListConverterTest {
 
   @RegisterExtension
   public final JpaUnitTestExtension jpaExtension =
-      new JpaTestRules.Builder().withEntityClass(TestEntity.class).buildUnitTestRule();
+      new JpaTestExtensions.Builder().withEntityClass(TestEntity.class).buildUnitTestExtension();
 
   @Test
   void roundTripConversion_returnsSameStringList() {

core/src/test/java/google/registry/persistence/converter/StringMapConverterBaseTest.java

@@ -22,8 +22,8 @@ import static org.junit.jupiter.api.Assertions.assertThrows;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.Maps;
 import google.registry.model.ImmutableObject;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaUnitTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaUnitTestExtension;
 import java.util.Map;
 import javax.persistence.Converter;
 import javax.persistence.Entity;
@@ -37,9 +37,9 @@ public class StringMapConverterBaseTest {
 
   @RegisterExtension
   public final JpaUnitTestExtension jpaExtension =
-      new JpaTestRules.Builder()
+      new JpaTestExtensions.Builder()
           .withEntityClass(TestStringMapConverter.class, TestEntity.class)
-          .buildUnitTestRule();
+          .buildUnitTestExtension();
 
   private static final ImmutableMap<Key, Value> MAP =
       ImmutableMap.of(

core/src/test/java/google/registry/persistence/converter/StringSetConverterTest.java

@@ -20,8 +20,8 @@ import static google.registry.testing.DatabaseHelper.insertInDb;
 
 import com.google.common.collect.ImmutableSet;
 import google.registry.model.ImmutableObject;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaUnitTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaUnitTestExtension;
 import java.util.Set;
 import javax.persistence.Entity;
 import javax.persistence.Id;
@@ -33,7 +33,7 @@ public class StringSetConverterTest {
 
   @RegisterExtension
   public final JpaUnitTestExtension jpaExtension =
-      new JpaTestRules.Builder().withEntityClass(TestEntity.class).buildUnitTestRule();
+      new JpaTestExtensions.Builder().withEntityClass(TestEntity.class).buildUnitTestExtension();
 
   @Test
   void roundTripConversion_returnsSameStringList() {

core/src/test/java/google/registry/persistence/converter/StringValueEnumeratedTest.java

@@ -20,8 +20,8 @@ import static google.registry.testing.DatabaseHelper.insertInDb;
 
 import google.registry.model.ImmutableObject;
 import google.registry.model.registrar.Registrar.State;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaUnitTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaUnitTestExtension;
 import javax.persistence.Entity;
 import javax.persistence.EnumType;
 import javax.persistence.Enumerated;
@@ -34,7 +34,7 @@ public class StringValueEnumeratedTest {
 
   @RegisterExtension
   public final JpaUnitTestExtension jpaExtension =
-      new JpaTestRules.Builder().withEntityClass(TestEntity.class).buildUnitTestRule();
+      new JpaTestExtensions.Builder().withEntityClass(TestEntity.class).buildUnitTestExtension();
 
   @Test
   void roundTripConversion_returnsSameEnum() {

core/src/test/java/google/registry/persistence/converter/TimedTransitionPropertyConverterBaseTest.java

@@ -25,8 +25,8 @@ import com.google.common.collect.Maps;
 import google.registry.model.ImmutableObject;
 import google.registry.model.common.TimedTransitionProperty;
 import google.registry.model.common.TimedTransitionProperty.TimedTransition;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaUnitTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaUnitTestExtension;
 import java.util.Map;
 import javax.persistence.Converter;
 import javax.persistence.Entity;
@@ -41,9 +41,9 @@ class TimedTransitionPropertyConverterBaseTest {
 
   @RegisterExtension
   public final JpaUnitTestExtension jpa =
-      new JpaTestRules.Builder()
+      new JpaTestExtensions.Builder()
           .withEntityClass(TestTimedTransitionPropertyConverter.class, TestEntity.class)
-          .buildUnitTestRule();
+          .buildUnitTestExtension();
 
   private static final DateTime DATE_1 = DateTime.parse("2001-01-01T00:00:00.000Z");
   private static final DateTime DATE_2 = DateTime.parse("2002-01-01T00:00:00.000Z");

core/src/test/java/google/registry/persistence/converter/TldStateTransitionConverterTest.java

@@ -24,8 +24,8 @@ import google.registry.model.ImmutableObject;
 import google.registry.model.common.TimedTransitionProperty;
 import google.registry.model.tld.Registry.TldState;
 import google.registry.model.tld.Registry.TldStateTransition;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaUnitTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaUnitTestExtension;
 import javax.persistence.Entity;
 import javax.persistence.Id;
 import org.joda.time.DateTime;
@@ -37,9 +37,7 @@ class TldStateTransitionConverterTest {
 
   @RegisterExtension
   public final JpaUnitTestExtension jpa =
-      new JpaTestRules.Builder()
+      new JpaTestExtensions.Builder().withEntityClass(TestEntity.class).buildUnitTestExtension();
-          .withEntityClass(TestEntity.class)
-          .buildUnitTestRule();
 
   private static final ImmutableSortedMap<DateTime, TldState> values =
       ImmutableSortedMap.of(

core/src/test/java/google/registry/persistence/converter/ZonedDateTimeConverterTest.java

@@ -19,8 +19,8 @@ import static google.registry.persistence.transaction.TransactionManagerFactory.
 import static google.registry.testing.DatabaseHelper.insertInDb;
 
 import google.registry.model.ImmutableObject;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaUnitTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaUnitTestExtension;
 import java.sql.Timestamp;
 import java.time.Instant;
 import java.time.ZonedDateTime;
@@ -34,7 +34,7 @@ public class ZonedDateTimeConverterTest {
 
   @RegisterExtension
   public final JpaUnitTestExtension jpaExtension =
-      new JpaTestRules.Builder().withEntityClass(TestEntity.class).buildUnitTestRule();
+      new JpaTestExtensions.Builder().withEntityClass(TestEntity.class).buildUnitTestExtension();
 
   private final ZonedDateTimeConverter converter = new ZonedDateTimeConverter();
 

core/src/test/java/google/registry/persistence/transaction/CriteriaQueryBuilderTest.java

@@ -19,7 +19,7 @@ import static google.registry.persistence.transaction.TransactionManagerFactory.
 
 import com.google.common.collect.ImmutableList;
 import google.registry.model.ImmutableObject;
-import google.registry.persistence.transaction.JpaTestRules.JpaUnitTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaUnitTestExtension;
 import google.registry.testing.FakeClock;
 import java.util.List;
 import javax.persistence.Entity;
@@ -42,10 +42,10 @@ class CriteriaQueryBuilderTest {
 
   @RegisterExtension
   final JpaUnitTestExtension jpaExtension =
-      new JpaTestRules.Builder()
+      new JpaTestExtensions.Builder()
           .withClock(fakeClock)
           .withEntityClass(CriteriaQueryBuilderTestEntity.class)
-          .buildUnitTestRule();
+          .buildUnitTestExtension();
 
   @BeforeEach
   void beforeEach() {

core/src/test/java/google/registry/persistence/transaction/JpaTestExtensions.java

@@ -35,18 +35,18 @@ import org.junit.jupiter.api.extension.BeforeEachCallback;
 import org.junit.jupiter.api.extension.ExtensionContext;
 
 /**
- * Holds specialized JUnit rules that start a test database server and provide {@link
+ * Holds specialized JUnit extensions that start a test database server and provide {@link
  * JpaTransactionManager} instances.
  */
-public class JpaTestRules {
+public class JpaTestExtensions {
 
   private static final String GOLDEN_SCHEMA_SQL_PATH = "sql/schema/nomulus.golden.sql";
   private static final String HSTORE_EXTENSION_SQL_PATH =
       "sql/flyway/V14__load_extension_for_hstore.sql";
 
   /**
-   * Junit rule for integration tests with JPA framework, when the underlying database is populated
+   * JUnit extension for integration tests with JPA framework, when the underlying database is
-   * with the Nomulus Cloud SQL schema.
+   * populated with the Nomulus Cloud SQL schema.
    */
   public static class JpaIntegrationTestExtension extends JpaTransactionManagerExtension {
     private JpaIntegrationTestExtension(
@@ -83,26 +83,26 @@ public class JpaTestRules {
       implements BeforeEachCallback, AfterEachCallback {
 
     private final JpaEntityCoverageExtension jpaEntityCoverage = new JpaEntityCoverageExtension();
-    private final JpaIntegrationTestExtension integrationTestRule;
+    private final JpaIntegrationTestExtension integrationTestExtension;
 
-    JpaIntegrationWithCoverageExtension(JpaIntegrationTestExtension integrationTestRule) {
+    JpaIntegrationWithCoverageExtension(JpaIntegrationTestExtension integrationTestExtension) {
-      this.integrationTestRule = integrationTestRule;
+      this.integrationTestExtension = integrationTestExtension;
     }
 
     @Override
     public void beforeEach(ExtensionContext context) throws Exception {
-      integrationTestRule.beforeEach(context);
+      integrationTestExtension.beforeEach(context);
       jpaEntityCoverage.beforeEach(context);
     }
 
     @Override
     public void afterEach(ExtensionContext context) {
       jpaEntityCoverage.afterEach(context);
-      integrationTestRule.afterEach(context);
+      integrationTestExtension.afterEach(context);
     }
   }
 
-  /** Builder of test rules that provide {@link JpaTransactionManager}. */
+  /** Builder of test extensions that provide {@link JpaTransactionManager}. */
   public static class Builder {
 
     private String initScript;
@@ -150,7 +150,7 @@ public class JpaTestRules {
     }
 
     /** Builds a {@link JpaIntegrationTestExtension} instance. */
-    public JpaIntegrationTestExtension buildIntegrationTestRule() {
+    public JpaIntegrationTestExtension buildIntegrationTestExtension() {
       return new JpaIntegrationTestExtension(
           clock == null ? new FakeClock(DateTime.now(UTC)) : clock,
           ImmutableList.copyOf(extraEntityClasses),
@@ -163,14 +163,14 @@ public class JpaTestRules {
      */
     public JpaIntegrationWithCoverageExtension buildIntegrationWithCoverageExtension() {
       checkState(initScript == null, "Integration tests do not accept initScript");
-      return new JpaIntegrationWithCoverageExtension(buildIntegrationTestRule());
+      return new JpaIntegrationWithCoverageExtension(buildIntegrationTestExtension());
     }
 
     /**
      * Builds a {@link JpaUnitTestExtension} instance that can also be used as an extension for
      * JUnit5.
      */
-    public JpaUnitTestExtension buildUnitTestRule() {
+    public JpaUnitTestExtension buildUnitTestExtension() {
       checkState(
           !Objects.equals(GOLDEN_SCHEMA_SQL_PATH, initScript),
           "Unit tests must not depend on the Nomulus schema.");

core/src/test/java/google/registry/persistence/transaction/JpaTestExtensionsSqlLoggingTest.java

@@ -18,7 +18,7 @@ import static com.google.common.truth.Truth.assertThat;
 import static google.registry.persistence.transaction.TransactionManagerFactory.jpaTm;
 import static java.nio.charset.StandardCharsets.UTF_8;
 
-import google.registry.persistence.transaction.JpaTestRules.JpaUnitTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaUnitTestExtension;
 import java.io.ByteArrayOutputStream;
 import java.io.PrintStream;
 import java.io.UnsupportedEncodingException;
@@ -27,13 +27,13 @@ import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.RegisterExtension;
 
-/** Unit test for {@link JpaTestRules.Builder#withSqlLogging()}. */
+/** Unit test for {@link JpaTestExtensions.Builder#withSqlLogging()}. */
-class JpaTestRulesSqlLoggingTest {
+class JpaTestExtensionsSqlLoggingTest {
 
   // Entity under test: configured to log SQL statements to Stdout.
   @RegisterExtension
   JpaUnitTestExtension jpaExtension =
-      new JpaTestRules.Builder().withSqlLogging().buildUnitTestRule();
+      new JpaTestExtensions.Builder().withSqlLogging().buildUnitTestExtension();
 
   private PrintStream orgStdout;
   private ByteArrayOutputStream stdoutBuffer;

core/src/test/java/google/registry/persistence/transaction/JpaTransactionManagerExtension.java

@@ -32,8 +32,8 @@ import google.registry.persistence.HibernateSchemaExporter;
 import google.registry.persistence.NomulusPostgreSql;
 import google.registry.persistence.PersistenceModule;
 import google.registry.persistence.PersistenceXmlUtility;
-import google.registry.persistence.transaction.JpaTestRules.JpaIntegrationTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaIntegrationTestExtension;
-import google.registry.persistence.transaction.JpaTestRules.JpaUnitTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaUnitTestExtension;
 import google.registry.util.Clock;
 import java.io.File;
 import java.io.IOException;
@@ -71,8 +71,8 @@ import org.testcontainers.containers.PostgreSQLContainer;
  * <p>This class is not for direct use. Use the specialized subclasses {@link
  * JpaIntegrationTestExtension} or {@link JpaUnitTestExtension} as befits the use case.
  *
- * <p>This rule also replaces the {@link JpaTransactionManagerImpl} provided by {@link
+ * <p>This extension also replaces the {@link JpaTransactionManagerImpl} provided by {@link
- * TransactionManagerFactory} with the {@link JpaTransactionManagerImpl} generated by the rule
+ * TransactionManagerFactory} with the {@link JpaTransactionManagerImpl} generated by the extension
  * itself, so that all SQL queries will be sent to the database instance created by {@link
  * PostgreSQLContainer} to achieve test purpose.
  */
@@ -102,11 +102,11 @@ abstract class JpaTransactionManagerExtension implements BeforeEachCallback, Aft
   private static int emfEntityHash;
 
   private JpaTransactionManager cachedTm;
-  // Hash of the ORM entity names requested by this rule instance.
+  // Hash of the ORM entity names requested by this extension instance.
   private final int entityHash;
 
-  // Whether to create nomulus tables in the test db. Right now, only the JpaTestRules set this to
+  // Whether to create nomulus tables in the test db. Right now, only the JpaTestExtensions set this
-  // false.
+  // to false.
   private boolean includeNomulusSchema = true;
 
   JpaTransactionManagerExtension(

core/src/test/java/google/registry/persistence/transaction/JpaTransactionManagerExtensionTest.java

@@ -20,7 +20,7 @@ import static google.registry.testing.DatabaseHelper.insertInDb;
 import static org.junit.jupiter.api.Assertions.assertThrows;
 
 import google.registry.model.ImmutableObject;
-import google.registry.persistence.transaction.JpaTestRules.JpaUnitTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaUnitTestExtension;
 import java.util.List;
 import javax.persistence.Entity;
 import javax.persistence.Id;
@@ -32,14 +32,14 @@ import org.junit.jupiter.api.extension.RegisterExtension;
  * JUnit test for {@link JpaTransactionManagerExtension}, with {@link JpaUnitTestExtension} as
  * proxy.
  */
-public class JpaTransactionManagerRuleTest {
+public class JpaTransactionManagerExtensionTest {
 
   @RegisterExtension
   public final JpaUnitTestExtension jpaExtension =
-      new JpaTestRules.Builder().withEntityClass(TestEntity.class).buildUnitTestRule();
+      new JpaTestExtensions.Builder().withEntityClass(TestEntity.class).buildUnitTestExtension();
 
   @Test
-  void verifiesRuleWorks() {
+  void verifiesExtensionWorks() {
     assertThrows(
         PersistenceException.class,
         () ->

core/src/test/java/google/registry/persistence/transaction/JpaTransactionManagerImplTest.java

@@ -31,7 +31,7 @@ import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import google.registry.model.ImmutableObject;
 import google.registry.persistence.VKey;
-import google.registry.persistence.transaction.JpaTestRules.JpaUnitTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaUnitTestExtension;
 import google.registry.testing.DatabaseHelper;
 import google.registry.testing.FakeClock;
 import java.io.Serializable;
@@ -73,12 +73,12 @@ class JpaTransactionManagerImplTest {
 
   @RegisterExtension
   final JpaUnitTestExtension jpaExtension =
-      new JpaTestRules.Builder()
+      new JpaTestExtensions.Builder()
           .withInitScript(fileClassPath(getClass(), "test_schema.sql"))
           .withClock(fakeClock)
           .withEntityClass(
               TestEntity.class, TestCompoundIdEntity.class, TestNamedCompoundIdEntity.class)
-          .buildUnitTestRule();
+          .buildUnitTestExtension();
 
   @Test
   void transact_succeeds() {

core/src/test/java/google/registry/rdap/UpdateRegistrarRdapBaseUrlsActionTest.java

@@ -78,7 +78,7 @@ public final class UpdateRegistrarRdapBaseUrlsActionTest {
           + "\"version\":\"1.0\"}";
 
   @RegisterExtension
-  public AppEngineExtension appEngineRule =
+  public AppEngineExtension appEngineExtension =
       new AppEngineExtension.Builder().withDatastoreAndCloudSql().build();
 
   private static class TestHttpTransport extends MockHttpTransport {

core/src/test/java/google/registry/rde/RdeStagingMapperTest.java

@@ -54,14 +54,14 @@ class RdeStagingMapperTest {
       ArgumentCaptor.forClass(DepositFragment.class);
 
   @RegisterExtension
-  AppEngineExtension appEngineRule =
+  AppEngineExtension appEngineExtension =
       AppEngineExtension.builder().withDatastoreAndCloudSql().build();
 
   private RdeStagingMapper rdeStagingMapper;
 
   @BeforeEach
   void beforeEach() {
-    // Two real registrars have been created by AppEngineRule, named "New Registrar" and "The
+    // Two real registrars have been created by AppEngineExtension, named "New Registrar" and "The
     // Registrar". Create one included registrar (external_monitoring) and two excluded ones.
     Registrar monitoringRegistrar =
         persistNewRegistrar("monitoring", "monitoring", Registrar.Type.MONITORING, null);

core/src/test/java/google/registry/rde/RdeStagingReducerTest.java

@@ -64,7 +64,7 @@ import org.junit.jupiter.api.extension.RegisterExtension;
 class RdeStagingReducerTest {
 
   @RegisterExtension
-  AppEngineExtension appEngineRule =
+  AppEngineExtension appEngineExtension =
       AppEngineExtension.builder().withDatastoreAndCloudSql().withTaskQueue().build();
 
   private static final String GCS_BUCKET = "test-rde-bucket";

core/src/test/java/google/registry/reporting/icann/IcannHttpReporterTest.java

@@ -49,7 +49,7 @@ class IcannHttpReporterTest {
   private MockLowLevelHttpRequest mockRequest;
 
   @RegisterExtension
-  AppEngineExtension appEngineRule =
+  AppEngineExtension appEngineExtension =
       new AppEngineExtension.Builder().withDatastoreAndCloudSql().build();
 
   private MockHttpTransport createMockTransport(

core/src/test/java/google/registry/schema/integration/SqlIntegrationTestSuite.java

@@ -38,7 +38,7 @@ import google.registry.model.tld.label.ReservedListDaoTest;
 import google.registry.model.tmch.ClaimsListDaoTest;
 import google.registry.model.tmch.TmchCrlTest;
 import google.registry.persistence.transaction.JpaEntityCoverageExtension;
-import google.registry.persistence.transaction.JpaTestRules.JpaIntegrationWithCoverageExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaIntegrationWithCoverageExtension;
 import google.registry.schema.integration.SqlIntegrationTestSuite.AfterSuiteTest;
 import google.registry.schema.integration.SqlIntegrationTestSuite.BeforeSuiteTest;
 import google.registry.schema.registrar.RegistrarDaoTest;

core/src/test/java/google/registry/schema/registrar/RegistrarContactTest.java

@@ -23,8 +23,8 @@ import static google.registry.testing.SqlHelper.saveRegistrar;
 import com.google.common.collect.ImmutableSet;
 import google.registry.model.registrar.Registrar;
 import google.registry.model.registrar.RegistrarContact;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaIntegrationWithCoverageExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaIntegrationWithCoverageExtension;
 import google.registry.testing.DatastoreEntityExtension;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Order;
@@ -40,7 +40,7 @@ class RegistrarContactTest {
 
   @RegisterExtension
   JpaIntegrationWithCoverageExtension jpa =
-      new JpaTestRules.Builder().buildIntegrationWithCoverageExtension();
+      new JpaTestExtensions.Builder().buildIntegrationWithCoverageExtension();
 
   private Registrar testRegistrar;
 

core/src/test/java/google/registry/schema/registrar/RegistrarDaoTest.java

@@ -24,8 +24,8 @@ import com.google.common.collect.ImmutableList;
 import google.registry.model.registrar.Registrar;
 import google.registry.model.registrar.RegistrarAddress;
 import google.registry.persistence.VKey;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaIntegrationWithCoverageExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaIntegrationWithCoverageExtension;
 import google.registry.testing.DatastoreEntityExtension;
 import google.registry.testing.FakeClock;
 import org.joda.time.DateTime;
@@ -45,7 +45,7 @@ public class RegistrarDaoTest {
 
   @RegisterExtension
   JpaIntegrationWithCoverageExtension jpa =
-      new JpaTestRules.Builder().withClock(fakeClock).buildIntegrationWithCoverageExtension();
+      new JpaTestExtensions.Builder().withClock(fakeClock).buildIntegrationWithCoverageExtension();
 
   private final VKey<Registrar> registrarKey = VKey.createSql(Registrar.class, "registrarId");
 

core/src/test/java/google/registry/server/RegistryTestServerMain.java

@@ -19,7 +19,7 @@ import com.beust.jcommander.Parameter;
 import com.beust.jcommander.Parameters;
 import com.google.common.collect.ImmutableList;
 import com.google.common.net.HostAndPort;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
 import google.registry.testing.AppEngineExtension;
 import google.registry.testing.UserInfo;
 import google.registry.tools.params.HostAndPortParameter;
@@ -134,7 +134,7 @@ public final class RegistryTestServerMain {
 
     final RegistryTestServer server = new RegistryTestServer(address);
 
-    System.out.printf("%sLoading SQL fixtures and AppEngineRule...%s\n", BLUE, RESET);
+    System.out.printf("%sLoading SQL fixtures and AppEngineExtension...%s\n", BLUE, RESET);
     AppEngineExtension appEngine =
         AppEngineExtension.builder()
             .withDatastoreAndCloudSql()
@@ -148,7 +148,7 @@ public final class RegistryTestServerMain {
             .build();
     appEngine.setUp();
     AppEngineExtension.loadInitialData();
-    new JpaTestRules.Builder().buildIntegrationTestRule().beforeEach(null);
+    new JpaTestExtensions.Builder().buildIntegrationTestExtension().beforeEach(null);
     System.out.printf("%sLoading Datastore fixtures...%s\n", BLUE, RESET);
     for (Fixture fixture : fixtures) {
       fixture.load();

core/src/test/java/google/registry/testing/AppEngineExtension.java

@@ -50,10 +50,10 @@ import google.registry.model.registrar.Registrar;
 import google.registry.model.registrar.Registrar.State;
 import google.registry.model.registrar.RegistrarAddress;
 import google.registry.model.registrar.RegistrarContact;
-import google.registry.persistence.transaction.JpaTestRules;
+import google.registry.persistence.transaction.JpaTestExtensions;
-import google.registry.persistence.transaction.JpaTestRules.JpaIntegrationTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaIntegrationTestExtension;
-import google.registry.persistence.transaction.JpaTestRules.JpaIntegrationWithCoverageExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaIntegrationWithCoverageExtension;
-import google.registry.persistence.transaction.JpaTestRules.JpaUnitTestExtension;
+import google.registry.persistence.transaction.JpaTestExtensions.JpaUnitTestExtension;
 import google.registry.util.Clock;
 import java.io.ByteArrayInputStream;
 import java.io.File;
@@ -106,7 +106,8 @@ public final class AppEngineExtension implements BeforeEachCallback, AfterEachCa
   private LocalServiceTestHelper helper;
 
   /**
-   * A temporary directory for AppEngineRule's internal temp files that is different for each test.
+   * A temporary directory for AppEngineExtension's internal temp files that is different for each
+   * test.
    *
    * <p>Note that we can't use {@link TempDir} here because that only works in test classes, not
    * extensions.
@@ -117,7 +118,7 @@ public final class AppEngineExtension implements BeforeEachCallback, AfterEachCa
    * Sets up a SQL database. This is for test classes that are not a member of the {@code
    * SqlIntegrationTestSuite}.
    */
-  private JpaIntegrationTestExtension jpaIntegrationTestRule = null;
+  private JpaIntegrationTestExtension jpaIntegrationTestExtension = null;
 
   /**
    * Sets up a SQL database and records the JPA entities tested by each test class. This is for
@@ -125,7 +126,7 @@ public final class AppEngineExtension implements BeforeEachCallback, AfterEachCa
    */
   private JpaIntegrationWithCoverageExtension jpaIntegrationWithCoverageExtension = null;
 
-  private JpaUnitTestExtension jpaUnitTestRule;
+  private JpaUnitTestExtension jpaUnitTestExtension;
 
   private boolean withDatastore;
   private boolean withoutCannedData;
@@ -141,34 +142,34 @@ public final class AppEngineExtension implements BeforeEachCallback, AfterEachCa
   private String taskQueueXml;
   private UserInfo userInfo;
 
-  // Test Objectify entity classes to be used with this AppEngineRule instance.
+  // Test Objectify entity classes to be used with this AppEngineExtension instance.
   private ImmutableList<Class<?>> ofyTestEntities;
   private ImmutableList<Class<?>> jpaTestEntities;
 
   /** Builder for {@link AppEngineExtension}. */
   public static class Builder {
 
-    private AppEngineExtension rule = new AppEngineExtension();
+    private AppEngineExtension extension = new AppEngineExtension();
     private ImmutableList.Builder<Class<?>> ofyTestEntities = new ImmutableList.Builder<>();
     private ImmutableList.Builder<Class<?>> jpaTestEntities = new ImmutableList.Builder<>();
 
     /** Turn on the Datastore service and the Cloud SQL service. */
     public Builder withDatastoreAndCloudSql() {
-      rule.withDatastore = true;
+      extension.withDatastore = true;
-      rule.withCloudSql = true;
+      extension.withCloudSql = true;
       return this;
     }
 
     /** Turns on Cloud SQL only, for use by test data generators. */
     public Builder withCloudSql() {
-      rule.withCloudSql = true;
+      extension.withCloudSql = true;
-      rule.withDatastore = false;
+      extension.withDatastore = false;
       return this;
     }
 
     /** Disables insertion of canned data. */
     public Builder withoutCannedData() {
-      rule.withoutCannedData = true;
+      extension.withoutCannedData = true;
       return this;
     }
 
@@ -177,13 +178,13 @@ public final class AppEngineExtension implements BeforeEachCallback, AfterEachCa
      * members of SqlIntegrationTestSuite.
      */
     public Builder enableJpaEntityCoverageCheck(boolean enabled) {
-      rule.enableJpaEntityCoverageCheck = enabled;
+      extension.enableJpaEntityCoverageCheck = enabled;
       return this;
     }
 
     /** Turn on the use of local modules. */
     public Builder withLocalModules() {
-      rule.withLocalModules = true;
+      extension.withLocalModules = true;
       return this;
     }
 
@@ -194,25 +195,25 @@ public final class AppEngineExtension implements BeforeEachCallback, AfterEachCa
 
     /** Turn on the task queue service with a specified set of queues. */
     public Builder withTaskQueue(String taskQueueXml) {
-      rule.withTaskQueue = true;
+      extension.withTaskQueue = true;
-      rule.taskQueueXml = taskQueueXml;
+      extension.taskQueueXml = taskQueueXml;
       return this;
     }
 
     /** Turn on the URL Fetch service. */
     public Builder withUrlFetch() {
-      rule.withUrlFetch = true;
+      extension.withUrlFetch = true;
       return this;
     }
 
     public Builder withClock(Clock clock) {
-      rule.clock = clock;
+      extension.clock = clock;
       return this;
     }
 
     public Builder withUserService(UserInfo userInfo) {
-      rule.withUserService = true;
+      extension.withUserService = true;
-      rule.userInfo = userInfo;
+      extension.userInfo = userInfo;
       return this;
     }
 
@@ -236,23 +237,23 @@ public final class AppEngineExtension implements BeforeEachCallback, AfterEachCa
 
     public Builder withJpaUnitTestEntities(Class<?>... entities) {
       jpaTestEntities.add(entities);
-      rule.withJpaUnitTest = true;
+      extension.withJpaUnitTest = true;
       return this;
     }
 
     public AppEngineExtension build() {
       checkState(
-          !rule.enableJpaEntityCoverageCheck || rule.withCloudSql,
+          !extension.enableJpaEntityCoverageCheck || extension.withCloudSql,
           "withJpaEntityCoverageCheck enabled without Cloud SQL");
       checkState(
-          !rule.withJpaUnitTest || rule.withCloudSql,
+          !extension.withJpaUnitTest || extension.withCloudSql,
           "withJpaUnitTestEntities enabled without Cloud SQL");
       checkState(
-          !rule.withJpaUnitTest || !rule.enableJpaEntityCoverageCheck,
+          !extension.withJpaUnitTest || !extension.enableJpaEntityCoverageCheck,
           "withJpaUnitTestEntities cannot be set when enableJpaEntityCoverageCheck");
-      rule.ofyTestEntities = this.ofyTestEntities.build();
+      extension.ofyTestEntities = this.ofyTestEntities.build();
-      rule.jpaTestEntities = this.jpaTestEntities.build();
+      extension.jpaTestEntities = this.jpaTestEntities.build();
-      return rule;
+      return extension;
     }
   }
 
@@ -366,8 +367,8 @@ public final class AppEngineExtension implements BeforeEachCallback, AfterEachCa
     checkArgumentNotNull(context, "The ExtensionContext must not be null");
     setUp();
     if (withCloudSql) {
-      JpaTestRules.Builder builder =
+      JpaTestExtensions.Builder builder =
-          new JpaTestRules.Builder().withEntityClass(jpaTestEntities.toArray(new Class[0]));
+          new JpaTestExtensions.Builder().withEntityClass(jpaTestEntities.toArray(new Class[0]));
       if (clock != null) {
         builder.withClock(clock);
       }
@@ -375,11 +376,11 @@ public final class AppEngineExtension implements BeforeEachCallback, AfterEachCa
         jpaIntegrationWithCoverageExtension = builder.buildIntegrationWithCoverageExtension();
         jpaIntegrationWithCoverageExtension.beforeEach(context);
       } else if (withJpaUnitTest) {
-        jpaUnitTestRule = builder.buildUnitTestRule();
+        jpaUnitTestExtension = builder.buildUnitTestExtension();
-        jpaUnitTestRule.beforeEach(context);
+        jpaUnitTestExtension.beforeEach(context);
       } else {
-        jpaIntegrationTestRule = builder.buildIntegrationTestRule();
+        jpaIntegrationTestExtension = builder.buildIntegrationTestExtension();
-        jpaIntegrationTestRule.beforeEach(context);
+        jpaIntegrationTestExtension.beforeEach(context);
       }
     }
     if (isWithDatastoreAndCloudSql()) {
@@ -491,9 +492,9 @@ public final class AppEngineExtension implements BeforeEachCallback, AfterEachCa
         if (enableJpaEntityCoverageCheck) {
           jpaIntegrationWithCoverageExtension.afterEach(context);
         } else if (withJpaUnitTest) {
-          jpaUnitTestRule.afterEach(context);
+          jpaUnitTestExtension.afterEach(context);
         } else {
-          jpaIntegrationTestRule.afterEach(context);
+          jpaIntegrationTestExtension.afterEach(context);
         }
       }
       tearDown();

core/src/test/java/google/registry/testing/AppEngineExtensionTest.java

@@ -123,7 +123,7 @@ class AppEngineExtensionTest {
 
   @Test
   void testRegisterOfyEntities_duplicateEntitiesWithSameName_fails() throws Exception {
-    AppEngineExtension appEngineRule =
+    AppEngineExtension appEngineExtension =
         AppEngineExtension.builder()
             .withDatastoreAndCloudSql()
             .withOfyTestEntities(google.registry.testing.TestObject.class, TestObject.class)
@@ -131,7 +131,7 @@ class AppEngineExtensionTest {
     // Thrown before JPA is set up, therefore no need to call afterEach.
     IllegalStateException thrown =
         assertThrows(
-            IllegalStateException.class, () -> appEngineRule.beforeEach(context.getContext()));
+            IllegalStateException.class, () -> appEngineExtension.beforeEach(context.getContext()));
     assertThat(thrown)
         .hasMessageThat()
         .isEqualTo(
@@ -167,7 +167,7 @@ class AppEngineExtensionTest {
               .collect(entriesToImmutableMap());
       assertWithMessage(
               "Conflicting Ofy kinds found. Tests will break if they are registered with "
-                  + " AppEngineRule in the same test executor.")
+                  + " AppEngineExtension in the same test executor.")
           .that(conflictingKinds)
           .isEmpty();
     }

core/src/test/java/google/registry/testing/DualDatabaseTestInvocationContextProvider.java

@@ -115,9 +115,9 @@ class DualDatabaseTestInvocationContextProvider implements TestTemplateInvocatio
                 appEngineExtensionFields.size()));
       }
       appEngineExtensionFields.get(0).setAccessible(true);
-      AppEngineExtension appEngineRule =
+      AppEngineExtension appEngineExtension =
           (AppEngineExtension) appEngineExtensionFields.get(0).get(testInstance);
-      if (!appEngineRule.isWithDatastoreAndCloudSql()) {
+      if (!appEngineExtension.isWithDatastoreAndCloudSql()) {
         throw new IllegalStateException(
             "AppEngineExtension in @DualDatabaseTest test must set withDatastoreAndCloudSql()");
       }

core/src/test/java/google/registry/testing/EppLoader.java

@@ -23,7 +23,7 @@ import google.registry.flows.EppException;
 import google.registry.model.eppinput.EppInput;
 import java.util.Map;
 
-/** Test rule that loads an Epp object from a file. */
+/** Test extension that loads an Epp object from a file. */
 public class EppLoader {
 
   private String eppXml;

core/src/test/java/google/registry/testing/FakeUserService.java

@@ -19,7 +19,7 @@ import com.google.appengine.api.users.UserService;
 import java.util.Set;
 import javax.annotation.Nullable;
 
-// TODO: Consider reconciling this with AppEngineRule.withUserService()
+// TODO: Consider reconciling this with AppEngineExtension.withUserService()
 
 /** Fake implementation of {@link UserService} for testing. */
 public class FakeUserService implements UserService {

core/src/test/java/google/registry/testing/GpgSystemCommandExtension.java

@@ -37,9 +37,9 @@ import org.junit.jupiter.api.extension.ExtensionContext;
 /**
  * GnuPG system command JUnit extension.
  *
- * <p>This rule creates a isolated environment for running the {@code gpg} command inside system
+ * <p>This extension creates a isolated environment for running the {@code gpg} command inside
- * integration tests. It reduces a lot of the boilerplate of setting up the shell environment and
+ * system integration tests. It reduces a lot of the boilerplate of setting up the shell environment
- * importing your keyrings into a temporary config folder.
+ * and importing your keyrings into a temporary config folder.
  */
 public final class GpgSystemCommandExtension implements BeforeEachCallback, AfterEachCallback {
 

core/src/test/java/google/registry/testing/InjectExtension.java

@@ -29,11 +29,11 @@ import org.junit.jupiter.api.extension.ExtensionContext;
 /**
  * JUnit extension for overriding {@code private static} fields during a test.
  *
- * <p>This rule uses reflection to change the value of a field while your test is running and then
+ * <p>This extension uses reflection to change the value of a field while your test is running and
- * restore it to its original value after it's done (even if the test fails). The injection will
+ * then restore it to its original value after it's done (even if the test fails). The injection
- * work even if the field is marked {@code private} (but not if it's {@code final}). The downside is
+ * will work even if the field is marked {@code private} (but not if it's {@code final}). The
- * that if you rename the field in the future, IDE refactoring won't be smart enough to update the
+ * downside is that if you rename the field in the future, IDE refactoring won't be smart enough to
- * injection site.
+ * update the injection site.
  *
  * <p>We encourage you to consider using {@link google.registry.util.NonFinalForTesting
  * &#064;NonFinalForTesting} to document your injected fields.

core/src/test/java/google/registry/testing/SystemPropertyExtension.java

@@ -31,8 +31,8 @@ import org.junit.jupiter.api.extension.ExtensionContext;
 /**
  * JUnit extension for overriding the values Java system properties during tests.
  *
- * <p>In most scenarios this class should be the last rule/extension to apply. In JUnit 5, apply
+ * <p>In most scenarios this class should be the last extension/extension to apply. In JUnit 5,
- * {@code @Order(value = Integer.MAX_VALUE)} to the extension.
+ * apply {@code @Order(value = Integer.MAX_VALUE)} to the extension.
  */
 public final class SystemPropertyExtension
     implements SystemPropertySetter, BeforeEachCallback, AfterEachCallback {
@@ -66,7 +66,8 @@ public final class SystemPropertyExtension
    * <p>It's safe to call this method multiple times with the same {@code key} within a single test.
    * Only the truly original property value will be restored at the end.
    *
-   * <p>This method can be called fluently when declaring the Rule field, or within a Test method.
+   * <p>This method can be called fluently when declaring the Extension field, or within a Test
+   * method.
    *
    * @see java.lang.System#setProperty(String, String)
    */

core/src/test/java/google/registry/testing/TestCacheExtension.java

@@ -29,8 +29,8 @@ import org.junit.jupiter.api.extension.ExtensionContext;
 /**
  * A JUnit extension that overloads cache expiry for tests.
  *
- * <p>This rule is necessary because many caches in the system are singleton and referenced through
+ * <p>This extension is necessary because many caches in the system are singleton and referenced
- * static fields.
+ * through static fields.
  */
 public class TestCacheExtension implements BeforeEachCallback, AfterEachCallback {
 

core/src/test/java/google/registry/tools/CreateRegistrarCommandTest.java

@@ -1705,7 +1705,7 @@ class CreateRegistrarCommandTest extends CommandTestCase<CreateRegistrarCommand>
   @TestOfyAndSql
   void testFailure_registrarNameSimilarToExisting() {
     // Note that "tHeRe GiStRaR" normalizes identically to "The Registrar", which is created by
-    // AppEngineRule.
+    // AppEngineExtension.
     IllegalArgumentException thrown =
         assertThrows(
             IllegalArgumentException.class,

core/src/test/java/google/registry/tools/DomainLockUtilsTest.java

@@ -76,7 +76,7 @@ public final class DomainLockUtilsTest {
   private DomainLockUtils domainLockUtils;
 
   @RegisterExtension
-  public final AppEngineExtension appEngineRule =
+  public final AppEngineExtension appEngineExtension =
       AppEngineExtension.builder()
           .withDatastoreAndCloudSql()
           .withClock(clock)

core/src/test/java/google/registry/tools/GetRegistrarCommandTest.java

@@ -25,13 +25,13 @@ class GetRegistrarCommandTest extends CommandTestCase<GetRegistrarCommand> {
 
   @Test
   void testSuccess() throws Exception {
-    // This registrar is created by AppEngineRule.
+    // This registrar is created by AppEngineExtension.
     runCommand("NewRegistrar");
   }
 
   @Test
   void testSuccess_multipleArguments() throws Exception {
-    // Registrars are created by AppEngineRule.
+    // Registrars are created by AppEngineExtension.
     runCommand("NewRegistrar", "TheRegistrar");
   }
 

core/src/test/java/google/registry/tools/ResaveEnvironmentEntitiesCommandTest.java

@@ -67,7 +67,7 @@ class ResaveEnvironmentEntitiesCommandTest
         loadRegistrar("TheRegistrar").getContacts();
     assertThat(savedEntities)
         .containsExactly(
-            // The Registrars and RegistrarContacts are created by AppEngineRule.
+            // The Registrars and RegistrarContacts are created by AppEngineExtension.
             loadRegistrar("TheRegistrar"),
             loadRegistrar("NewRegistrar"),
             Registry.get("tld"),

core/src/test/java/google/registry/tools/UpdateRegistrarCommandTest.java

@@ -877,7 +877,7 @@ class UpdateRegistrarCommandTest extends CommandTestCase<UpdateRegistrarCommand>
   @Test
   void testFailure_registrarNameSimilarToExisting() {
     // Note that "tHeRe GiStRaR" normalizes identically to "The Registrar", which is created by
-    // AppEngineRule.
+    // AppEngineExtension.
     assertThrows(
         IllegalArgumentException.class,
         () -> runCommand("--name tHeRe GiStRaR", "--force", "NewRegistrar"));

core/src/test/java/google/registry/ui/server/registrar/ConsoleOteSetupActionTest.java

@@ -63,7 +63,7 @@ import org.mockito.junit.jupiter.MockitoExtension;
 public final class ConsoleOteSetupActionTest {
 
   @RegisterExtension
-  public final AppEngineExtension appEngineRule =
+  public final AppEngineExtension appEngineExtension =
       AppEngineExtension.builder().withDatastoreAndCloudSql().build();
 
   @RegisterExtension

core/src/test/java/google/registry/ui/server/registrar/ConsoleRegistrarCreatorActionTest.java

@@ -66,7 +66,7 @@ import org.mockito.junit.jupiter.MockitoExtension;
 final class ConsoleRegistrarCreatorActionTest {
 
   @RegisterExtension
-  final AppEngineExtension appEngineRule =
+  final AppEngineExtension appEngineExtension =
       AppEngineExtension.builder().withDatastoreAndCloudSql().build();
 
   @RegisterExtension

core/src/test/java/google/registry/ui/server/registrar/RegistrarSettingsActionTestCase.java

@@ -104,7 +104,7 @@ public abstract class RegistrarSettingsActionTestCase {
     disallowRegistrarAccess(CLIENT_ID, "newtld");
 
     // Add a technical contact to the registrar (in addition to the default admin contact created by
-    // AppEngineRule).
+    // AppEngineExtension).
     techContact =
         getOnlyElement(loadRegistrar(CLIENT_ID).getContactsOfType(RegistrarContact.Type.TECH));
 

core/src/test/java/google/registry/ui/server/registrar/RegistryLockGetActionTest.java

@@ -58,7 +58,7 @@ final class RegistryLockGetActionTest {
   private final FakeClock fakeClock = new FakeClock();
 
   @RegisterExtension
-  final AppEngineExtension appEngineRule =
+  final AppEngineExtension appEngineExtension =
       AppEngineExtension.builder().withDatastoreAndCloudSql().withClock(fakeClock).build();
 
   private final FakeResponse response = new FakeResponse();

core/src/test/java/google/registry/ui/server/registrar/RegistryLockVerifyActionTest.java

@@ -68,7 +68,7 @@ final class RegistryLockVerifyActionTest {
   private final FakeClock fakeClock = new FakeClock();
 
   @RegisterExtension
-  final AppEngineExtension appEngineRule =
+  final AppEngineExtension appEngineExtension =
       AppEngineExtension.builder()
           .withDatastoreAndCloudSql()
           .withClock(fakeClock)

core/src/test/java/google/registry/util/RequestStatusCheckerImplTest.java

@@ -58,7 +58,7 @@ final class RequestStatusCheckerImplTest {
         });
   }
 
-  @RegisterExtension AppEngineExtension appEngineRule = AppEngineExtension.builder().build();
+  @RegisterExtension AppEngineExtension appEngineExtension = AppEngineExtension.builder().build();
 
   @BeforeEach
   void beforeEach() {

core/src/test/java/google/registry/webdriver/RegistrarConsoleScreenshotTest.java

@@ -61,8 +61,8 @@ class RegistrarConsoleScreenshotTest extends WebDriverTestCase {
               route("/registry-lock-verify", FrontendServlet.class))
           .setFilters(ObjectifyFilter.class, OfyFilter.class)
           .setFixtures(BASIC)
-          .setEmail("Marla.Singer@crr.com") // from AppEngineRule.makeRegistrarContact3
+          .setEmail("Marla.Singer@crr.com") // from AppEngineExtension.makeRegistrarContact3
-          .setGaeUserId("12345") // from AppEngineRule.makeRegistrarContact3
+          .setGaeUserId("12345") // from AppEngineExtension.makeRegistrarContact3
           .build();
 
   @RetryingTest(3)

core/src/test/java/google/registry/webdriver/TestServerExtension.java

@@ -46,15 +46,15 @@ import org.junit.jupiter.api.extension.ExtensionContext;
 /**
  * JUnit extension that sets up and tears down {@link TestServer}.
  *
- * <p><b>Warning:</b> App Engine testing environments are thread local. This rule will spawn that
+ * <p><b>Warning:</b> App Engine testing environments are thread local. This extension will spawn
- * testing environment in a separate thread from your unit tests. Therefore any modifications you
+ * that testing environment in a separate thread from your unit tests. Therefore any modifications
- * need to make to that testing environment (e.g. Datastore interactions) must be done through the
+ * you need to make to that testing environment (e.g. Datastore interactions) must be done through
- * {@link #runInAppEngineEnvironment(Callable)} method.
+ * the {@link #runInAppEngineEnvironment(Callable)} method.
  */
 public final class TestServerExtension implements BeforeEachCallback, AfterEachCallback {
 
   private final ImmutableList<Fixture> fixtures;
-  private final AppEngineExtension appEngineRule;
+  private final AppEngineExtension appEngineExtension;
   private final BlockingQueue<FutureTask<?>> jobs = new LinkedBlockingDeque<>();
   private final ImmutableMap<String, Path> runfiles;
   private final ImmutableList<Route> routes;
@@ -76,7 +76,7 @@ public final class TestServerExtension implements BeforeEachCallback, AfterEachC
     this.fixtures = fixtures;
     // We create an GAE-Admin user, and then use AuthenticatedRegistrarAccessor.bypassAdminCheck to
     // choose whether the user is an admin or not.
-    this.appEngineRule =
+    this.appEngineExtension =
         AppEngineExtension.builder()
             .withDatastoreAndCloudSql()
             .withLocalModules()
@@ -177,12 +177,12 @@ public final class TestServerExtension implements BeforeEachCallback, AfterEachC
     public void run() {
       try {
         try {
-          appEngineRule.beforeEach(context);
+          appEngineExtension.beforeEach(context);
           this.runInner();
         } catch (InterruptedException e) {
           // This is what we expect to happen.
         } finally {
-          appEngineRule.afterEach(context);
+          appEngineExtension.afterEach(context);
         }
       } catch (Throwable e) {
         throw new RuntimeException(e);
@@ -194,7 +194,7 @@ public final class TestServerExtension implements BeforeEachCallback, AfterEachC
         fixture.load();
       }
       testServer.start();
-      System.out.printf("TestServerRule is listening on: %s\n", testServer.getUrl("/"));
+      System.out.printf("TestServerExtension is listening on: %s\n", testServer.getUrl("/"));
       synchronized (TestServerExtension.this) {
         isRunning = true;
         TestServerExtension.this.notify();

networking/src/test/java/google/registry/networking/handler/NettyExtension.java

@@ -117,7 +117,7 @@ public final class NettyExtension implements AfterEachCallback {
   }
 
   void checkReady() {
-    checkState(clientChannel != null, "Must call setUpClient to finish NettyRule setup");
+    checkState(clientChannel != null, "Must call setUpClient to finish NettyExtension setup");
   }
 
   /**