Upgrade most of remaining tests from JUnit 4 to JUnit 5 (#708)

core/src/test/java/google/registry/beam/BeamUtilsTest.java

@@ -22,14 +22,11 @@ import org.apache.avro.Schema;
 import org.apache.avro.generic.GenericData;
 import org.apache.avro.generic.GenericRecord;
 import org.apache.beam.sdk.io.gcp.bigquery.SchemaAndRecord;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 
 /** Unit tests for {@link BeamUtils} */
-@RunWith(JUnit4.class)
-public class BeamUtilsTest {
+class BeamUtilsTest {
 
   private static final String GENERIC_SCHEMA =
       "{\"name\": \"AnObject\", "
@@ -41,8 +38,8 @@ public class BeamUtilsTest {
 
   private SchemaAndRecord schemaAndRecord;
 
-  @Before
-  public void initializeRecord() {
+  @BeforeEach
+  void beforeEach() {
     // Create a record with a given JSON schema.
     GenericRecord record = new GenericData.Record(new Schema.Parser().parse(GENERIC_SCHEMA));
     record.put("aString", "hello world");
@@ -51,26 +48,26 @@ public class BeamUtilsTest {
   }
 
   @Test
-  public void testExtractField_fieldExists_returnsExpectedStringValues() {
+  void testExtractField_fieldExists_returnsExpectedStringValues() {
     assertThat(BeamUtils.extractField(schemaAndRecord.getRecord(), "aString"))
         .isEqualTo("hello world");
     assertThat(BeamUtils.extractField(schemaAndRecord.getRecord(), "aFloat")).isEqualTo("2.54");
   }
 
   @Test
-  public void testExtractField_fieldDoesntExist_returnsNull() {
+  void testExtractField_fieldDoesntExist_returnsNull() {
     schemaAndRecord.getRecord().put("aFloat", null);
     assertThat(BeamUtils.extractField(schemaAndRecord.getRecord(), "aFloat")).isEqualTo("null");
     assertThat(BeamUtils.extractField(schemaAndRecord.getRecord(), "missing")).isEqualTo("null");
   }
 
   @Test
-  public void testCheckFieldsNotNull_noExceptionIfAllPresent() {
+  void testCheckFieldsNotNull_noExceptionIfAllPresent() {
     BeamUtils.checkFieldsNotNull(ImmutableList.of("aString", "aFloat"), schemaAndRecord);
   }
 
   @Test
-  public void testCheckFieldsNotNull_fieldMissing_throwsException() {
+  void testCheckFieldsNotNull_fieldMissing_throwsException() {
     IllegalStateException expected =
         assertThrows(
             IllegalStateException.class,

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

@@ -55,6 +55,7 @@ import org.junit.runners.JUnit4;
 // a wrapper.
 @RunWith(JUnit4.class)
 public class CommitLogTransformsTest implements Serializable {
+
   private static final DateTime START_TIME = DateTime.parse("2000-01-01T00:00:00.0Z");
 
   @Rule public final transient TemporaryFolder temporaryFolder = new TemporaryFolder();

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

@@ -29,14 +29,11 @@ import org.apache.avro.Schema;
 import org.apache.avro.generic.GenericData;
 import org.apache.avro.generic.GenericRecord;
 import org.apache.beam.sdk.io.gcp.bigquery.SchemaAndRecord;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 
 /** Unit tests for {@link BillingEvent} */
-@RunWith(JUnit4.class)
-public class BillingEventTest {
+class BillingEventTest {
 
   private static final String BILLING_EVENT_SCHEMA =
       "{\"name\": \"BillingEvent\", "
@@ -60,8 +57,8 @@ public class BillingEventTest {
 
   private SchemaAndRecord schemaAndRecord;
 
-  @Before
-  public void initializeRecord() {
+  @BeforeEach
+  void beforeEach() {
     // Create a record with a given JSON schema.
     schemaAndRecord = new SchemaAndRecord(createRecord(), null);
   }
@@ -86,7 +83,7 @@ public class BillingEventTest {
   }
 
   @Test
-  public void testParseBillingEventFromRecord_success() {
+  void testParseBillingEventFromRecord_success() {
     BillingEvent event = BillingEvent.parseFromRecord(schemaAndRecord);
     assertThat(event.id()).isEqualTo(1);
     assertThat(event.billingTime())
@@ -107,7 +104,7 @@ public class BillingEventTest {
   }
 
   @Test
-  public void testParseBillingEventFromRecord_sunriseCreate_reducedPrice_success() {
+  void testParseBillingEventFromRecord_sunriseCreate_reducedPrice_success() {
     schemaAndRecord.getRecord().put("flags", "SUNRISE");
     BillingEvent event = BillingEvent.parseFromRecord(schemaAndRecord);
     assertThat(event.amount()).isEqualTo(17.43);
@@ -115,7 +112,7 @@ public class BillingEventTest {
   }
 
   @Test
-  public void testParseBillingEventFromRecord_anchorTenant_zeroPrice_success() {
+  void testParseBillingEventFromRecord_anchorTenant_zeroPrice_success() {
     schemaAndRecord.getRecord().put("flags", "SUNRISE ANCHOR_TENANT");
     BillingEvent event = BillingEvent.parseFromRecord(schemaAndRecord);
     assertThat(event.amount()).isZero();
@@ -123,13 +120,13 @@ public class BillingEventTest {
   }
 
   @Test
-  public void testParseBillingEventFromRecord_nullValue_throwsException() {
+  void testParseBillingEventFromRecord_nullValue_throwsException() {
     schemaAndRecord.getRecord().put("tld", null);
     assertThrows(IllegalStateException.class, () -> BillingEvent.parseFromRecord(schemaAndRecord));
   }
 
   @Test
-  public void testConvertBillingEvent_toCsv() {
+  void testConvertBillingEvent_toCsv() {
     BillingEvent event = BillingEvent.parseFromRecord(schemaAndRecord);
     assertThat(event.toCsv())
         .isEqualTo(
@@ -138,7 +135,7 @@ public class BillingEventTest {
   }
 
   @Test
-  public void testConvertBillingEvent_nonNullPoNumber_toCsv() {
+  void testConvertBillingEvent_nonNullPoNumber_toCsv() {
     GenericRecord record = createRecord();
     record.put("poNumber", "905610");
     BillingEvent event = BillingEvent.parseFromRecord(new SchemaAndRecord(record, null));
@@ -149,13 +146,13 @@ public class BillingEventTest {
   }
 
   @Test
-  public void testGenerateBillingEventFilename() {
+  void testGenerateBillingEventFilename() {
     BillingEvent event = BillingEvent.parseFromRecord(schemaAndRecord);
     assertThat(event.toFilename("2017-10")).isEqualTo("invoice_details_2017-10_myRegistrar_test");
   }
 
   @Test
-  public void testGetInvoiceGroupingKey_fromBillingEvent() {
+  void testGetInvoiceGroupingKey_fromBillingEvent() {
     BillingEvent event = BillingEvent.parseFromRecord(schemaAndRecord);
     InvoiceGroupingKey invoiceKey = event.getInvoiceGroupingKey();
     assertThat(invoiceKey.startDate()).isEqualTo("2017-10-01");
@@ -169,7 +166,7 @@ public class BillingEventTest {
   }
 
   @Test
-  public void test_nonNullPoNumber() {
+  void test_nonNullPoNumber() {
     GenericRecord record = createRecord();
     record.put("poNumber", "905610");
     BillingEvent event = BillingEvent.parseFromRecord(new SchemaAndRecord(record, null));
@@ -179,7 +176,7 @@ public class BillingEventTest {
   }
 
   @Test
-  public void testConvertInvoiceGroupingKey_toCsv() {
+  void testConvertInvoiceGroupingKey_toCsv() {
     BillingEvent event = BillingEvent.parseFromRecord(schemaAndRecord);
     InvoiceGroupingKey invoiceKey = event.getInvoiceGroupingKey();
     assertThat(invoiceKey.toCsv(3L))
@@ -189,7 +186,7 @@ public class BillingEventTest {
   }
 
   @Test
-  public void testInvoiceGroupingKeyCoder_deterministicSerialization() throws IOException {
+  void testInvoiceGroupingKeyCoder_deterministicSerialization() throws IOException {
     InvoiceGroupingKey invoiceKey =
         BillingEvent.parseFromRecord(schemaAndRecord).getInvoiceGroupingKey();
     InvoiceGroupingKeyCoder coder = new InvoiceGroupingKeyCoder();
@@ -200,7 +197,7 @@ public class BillingEventTest {
   }
 
   @Test
-  public void testGetDetailReportHeader() {
+  void testGetDetailReportHeader() {
     assertThat(BillingEvent.getHeader())
         .isEqualTo(
             "id,billingTime,eventTime,registrarId,billingId,poNumber,tld,action,"
@@ -208,7 +205,7 @@ public class BillingEventTest {
   }
 
   @Test
-  public void testGetOverallInvoiceHeader() {
+  void testGetOverallInvoiceHeader() {
     assertThat(InvoiceGroupingKey.invoiceHeader())
         .isEqualTo("StartDate,EndDate,ProductAccountKey,Amount,AmountCurrency,BillingProductCode,"
             + "SalesChannel,LineItemType,UsageGroupingKey,Quantity,Description,UnitPrice,"

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

@@ -25,16 +25,13 @@ import org.apache.beam.sdk.io.FileBasedSink;
 import org.apache.beam.sdk.options.ValueProvider;
 import org.apache.beam.sdk.options.ValueProvider.StaticValueProvider;
 import org.apache.beam.sdk.transforms.SerializableFunction;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
 
 /** Unit tests for {@link InvoicingUtils}. */
-@RunWith(JUnit4.class)
-public class InvoicingUtilsTest {
+class InvoicingUtilsTest {
 
   @Test
-  public void testDestinationFunction_generatesProperFileParams() {
+  void testDestinationFunction_generatesProperFileParams() {
     SerializableFunction<BillingEvent, Params> destinationFunction =
         InvoicingUtils.makeDestinationFunction("my/directory", StaticValueProvider.of("2017-10"));
 
@@ -53,7 +50,7 @@ public class InvoicingUtilsTest {
   }
 
   @Test
-  public void testEmptyDestinationParams() {
+  void testEmptyDestinationParams() {
     assertThat(InvoicingUtils.makeEmptyDestinationParams("my/directory"))
         .isEqualTo(
             new Params()
@@ -63,7 +60,7 @@ public class InvoicingUtilsTest {
 
   /** Asserts that the instantiated sql template matches a golden expected file. */
   @Test
-  public void testMakeQueryProvider() {
+  void testMakeQueryProvider() {
     ValueProvider<String> queryProvider =
         InvoicingUtils.makeQueryProvider(StaticValueProvider.of("2017-10"), "my-project-id");
     assertThat(queryProvider.get()).isEqualTo(loadFile("billing_events_test.sql"));

core/src/test/java/google/registry/bigquery/BigqueryConnectionTest.java

@@ -1,31 +0,0 @@
-// Copyright 2017 The Nomulus Authors. All Rights Reserved.
-//
-// 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 google.registry.bigquery;
-
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
-
-/** Unit tests for {@link BigqueryConnection}. */
-@RunWith(JUnit4.class)
-public class BigqueryConnectionTest {
-
-  @Test
-  public void testNothing() {
-    // Placeholder test class for now.
-    // TODO(b/16569089): figure out a good way for testing our Bigquery usage overall - maybe unit
-    // tests here, maybe end-to-end testing.
-  }
-}

core/src/test/java/google/registry/bigquery/BigqueryUtilsTest.java

@@ -27,20 +27,18 @@ import com.google.api.services.bigquery.model.JobReference;
 import java.util.concurrent.TimeUnit;
 import org.joda.time.DateTime;
 import org.joda.time.DateTimeZone;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
 
 /** Unit tests for {@link BigqueryUtils}. */
-@RunWith(JUnit4.class)
-public class BigqueryUtilsTest {
+class BigqueryUtilsTest {
+
   private static final DateTime DATE_0 = DateTime.parse("2014-07-17T20:35:42Z");
   private static final DateTime DATE_1 = DateTime.parse("2014-07-17T20:35:42.1Z");
   private static final DateTime DATE_2 = DateTime.parse("2014-07-17T20:35:42.12Z");
   private static final DateTime DATE_3 = DateTime.parse("2014-07-17T20:35:42.123Z");
 
   @Test
-  public void test_toBigqueryTimestampString() {
+  void test_toBigqueryTimestampString() {
     assertThat(toBigqueryTimestampString(START_OF_TIME)).isEqualTo("1970-01-01 00:00:00.000");
     assertThat(toBigqueryTimestampString(DATE_0)).isEqualTo("2014-07-17 20:35:42.000");
     assertThat(toBigqueryTimestampString(DATE_1)).isEqualTo("2014-07-17 20:35:42.100");
@@ -50,7 +48,7 @@ public class BigqueryUtilsTest {
   }
 
   @Test
-  public void test_toBigqueryTimestampString_convertsToUtc() {
+  void test_toBigqueryTimestampString_convertsToUtc() {
     assertThat(toBigqueryTimestampString(START_OF_TIME.withZone(DateTimeZone.forOffsetHours(5))))
         .isEqualTo("1970-01-01 00:00:00.000");
     assertThat(toBigqueryTimestampString(DateTime.parse("1970-01-01T00:00:00-0500")))
@@ -58,13 +56,13 @@ public class BigqueryUtilsTest {
   }
 
   @Test
-  public void test_fromBigqueryTimestampString_startAndEndOfTime() {
+  void test_fromBigqueryTimestampString_startAndEndOfTime() {
     assertThat(fromBigqueryTimestampString("1970-01-01 00:00:00 UTC")).isEqualTo(START_OF_TIME);
     assertThat(fromBigqueryTimestampString("294247-01-10 04:00:54.775 UTC")).isEqualTo(END_OF_TIME);
   }
 
   @Test
-  public void test_fromBigqueryTimestampString_trailingZerosOkay() {
+  void test_fromBigqueryTimestampString_trailingZerosOkay() {
     assertThat(fromBigqueryTimestampString("2014-07-17 20:35:42 UTC")).isEqualTo(DATE_0);
     assertThat(fromBigqueryTimestampString("2014-07-17 20:35:42.0 UTC")).isEqualTo(DATE_0);
     assertThat(fromBigqueryTimestampString("2014-07-17 20:35:42.00 UTC")).isEqualTo(DATE_0);
@@ -78,27 +76,27 @@ public class BigqueryUtilsTest {
   }
 
   @Test
-  public void testFailure_fromBigqueryTimestampString_nonUtcTimeZone() {
+  void testFailure_fromBigqueryTimestampString_nonUtcTimeZone() {
     assertThrows(
         IllegalArgumentException.class,
         () -> fromBigqueryTimestampString("2014-01-01 01:01:01 +05:00"));
   }
 
   @Test
-  public void testFailure_fromBigqueryTimestampString_noTimeZone() {
+  void testFailure_fromBigqueryTimestampString_noTimeZone() {
     assertThrows(
         IllegalArgumentException.class, () -> fromBigqueryTimestampString("2014-01-01 01:01:01"));
   }
 
   @Test
-  public void testFailure_fromBigqueryTimestampString_tooManyMillisecondDigits() {
+  void testFailure_fromBigqueryTimestampString_tooManyMillisecondDigits() {
     assertThrows(
         IllegalArgumentException.class,
         () -> fromBigqueryTimestampString("2014-01-01 01:01:01.1234 UTC"));
   }
 
   @Test
-  public void test_toBigqueryTimestamp_timeunitConversion() {
+  void test_toBigqueryTimestamp_timeunitConversion() {
     assertThat(toBigqueryTimestamp(1234567890L, TimeUnit.SECONDS))
         .isEqualTo("1234567890.000000");
     assertThat(toBigqueryTimestamp(1234567890123L, TimeUnit.MILLISECONDS))
@@ -110,14 +108,14 @@ public class BigqueryUtilsTest {
   }
 
   @Test
-  public void test_toBigqueryTimestamp_timeunitConversionForZero() {
+  void test_toBigqueryTimestamp_timeunitConversionForZero() {
     assertThat(toBigqueryTimestamp(0L, TimeUnit.SECONDS)).isEqualTo("0.000000");
     assertThat(toBigqueryTimestamp(0L, TimeUnit.MILLISECONDS)).isEqualTo("0.000000");
     assertThat(toBigqueryTimestamp(0L, TimeUnit.MICROSECONDS)).isEqualTo("0.000000");
   }
 
   @Test
-  public void test_toBigqueryTimestamp_datetimeConversion() {
+  void test_toBigqueryTimestamp_datetimeConversion() {
     assertThat(toBigqueryTimestamp(START_OF_TIME)).isEqualTo("0.000000");
     assertThat(toBigqueryTimestamp(DATE_0)).isEqualTo("1405629342.000000");
     assertThat(toBigqueryTimestamp(DATE_1)).isEqualTo("1405629342.100000");
@@ -127,18 +125,18 @@ public class BigqueryUtilsTest {
   }
 
   @Test
-  public void test_toJobReferenceString_normalSucceeds() {
+  void test_toJobReferenceString_normalSucceeds() {
     assertThat(toJobReferenceString(new JobReference().setProjectId("foo").setJobId("bar")))
         .isEqualTo("foo:bar");
   }
 
   @Test
-  public void test_toJobReferenceString_emptyReferenceSucceeds() {
+  void test_toJobReferenceString_emptyReferenceSucceeds() {
     assertThat(toJobReferenceString(new JobReference())).isEqualTo("null:null");
   }
 
   @Test
-  public void test_toJobReferenceString_nullThrowsNpe() {
+  void test_toJobReferenceString_nullThrowsNpe() {
     assertThrows(NullPointerException.class, () -> toJobReferenceString(null));
   }
 }

core/src/test/java/google/registry/bigquery/CheckedBigqueryTest.java

@@ -29,15 +29,12 @@ import com.google.api.services.bigquery.model.TableFieldSchema;
 import com.google.api.services.bigquery.model.TableReference;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 import org.mockito.ArgumentCaptor;
 
 /** Unit tests for {@link CheckedBigquery}. */
-@RunWith(JUnit4.class)
-public class CheckedBigqueryTest {
+class CheckedBigqueryTest {
 
   private final Bigquery bigquery = mock(Bigquery.class);
   private final Bigquery.Datasets bigqueryDatasets = mock(Bigquery.Datasets.class);
@@ -48,8 +45,8 @@ public class CheckedBigqueryTest {
 
   private CheckedBigquery checkedBigquery;
 
-  @Before
-  public void before() throws Exception {
+  @BeforeEach
+  void beforeEach() throws Exception {
     when(bigquery.datasets()).thenReturn(bigqueryDatasets);
     when(bigqueryDatasets.insert(eq("Project-Id"), any(Dataset.class)))
         .thenReturn(bigqueryDatasetsInsert);
@@ -70,7 +67,7 @@ public class CheckedBigqueryTest {
   }
 
   @Test
-  public void testSuccess_datastoreCreation() throws Exception {
+  void testSuccess_datastoreCreation() throws Exception {
     checkedBigquery.ensureDataSetExists("Project-Id", "Dataset-Id");
 
     ArgumentCaptor<Dataset> datasetArg = ArgumentCaptor.forClass(Dataset.class);
@@ -83,7 +80,7 @@ public class CheckedBigqueryTest {
   }
 
   @Test
-  public void testSuccess_datastoreAndTableCreation() throws Exception {
+  void testSuccess_datastoreAndTableCreation() throws Exception {
     checkedBigquery.ensureDataSetAndTableExist("Project-Id", "Dataset2", "Table2");
 
     ArgumentCaptor<Dataset> datasetArg = ArgumentCaptor.forClass(Dataset.class);

core/src/test/java/google/registry/config/RegistryConfigTest.java

@@ -18,15 +18,13 @@ import static com.google.common.truth.Truth.assertThat;
 import static google.registry.config.RegistryConfig.CONFIG_SETTINGS;
 import static google.registry.config.RegistryConfig.ConfigModule.provideReservedTermsExportDisclaimer;
 
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
 
-@RunWith(JUnit4.class)
-public class RegistryConfigTest {
+/** Unit tests for {@link RegistryConfig}. */
+class RegistryConfigTest {
 
   @Test
-  public void test_reservedTermsExportDisclaimer_isPrependedWithOctothorpes() {
+  void test_reservedTermsExportDisclaimer_isPrependedWithOctothorpes() {
     assertThat(provideReservedTermsExportDisclaimer(CONFIG_SETTINGS.get()))
         .isEqualTo("# Disclaimer line 1.\n" + "# Line 2 is this 1.");
   }

core/src/test/java/google/registry/config/RegistryEnvironmentTest.java

@@ -14,16 +14,13 @@
 
 package google.registry.config;
 
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
 
 /** Unit tests for {@link RegistryEnvironment}. */
-@RunWith(JUnit4.class)
-public class RegistryEnvironmentTest {
+class RegistryEnvironmentTest {
 
   @Test
-  public void testGet() {
+  void testGet() {
     RegistryEnvironment.get();
   }
 }

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

@@ -26,20 +26,17 @@ import google.registry.util.TaskQueueUtils;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Optional;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
 
 /** Unit tests for {@link CommitLogFanoutAction}. */
-@RunWith(JUnit4.class)
-public class CommitLogFanoutActionTest {
+class CommitLogFanoutActionTest {
 
   private static final String ENDPOINT = "/the/servlet";
   private static final String QUEUE = "the-queue";
 
-  @Rule
-  public final AppEngineRule appEngine =
+  @RegisterExtension
+  final AppEngineRule appEngineRule =
       AppEngineRule.builder()
           .withDatastoreAndCloudSql()
           .withTaskQueue(
@@ -55,7 +52,7 @@ public class CommitLogFanoutActionTest {
           .build();
 
   @Test
-  public void testSuccess() {
+  void testSuccess() {
     CommitLogFanoutAction action = new CommitLogFanoutAction();
     action.taskQueueUtils = new TaskQueueUtils(new Retrier(null, 1));
     action.endpoint = ENDPOINT;

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

@@ -39,22 +39,19 @@ import google.registry.util.TaskQueueUtils;
 import java.util.List;
 import java.util.Optional;
 import java.util.stream.Stream;
-import org.junit.Before;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
 
 /** Unit tests for {@link TldFanoutAction}. */
-@RunWith(JUnit4.class)
-public class TldFanoutActionTest {
+class TldFanoutActionTest {
 
   private static final String ENDPOINT = "/the/servlet";
   private static final String QUEUE = "the-queue";
   private final FakeResponse response = new FakeResponse();
 
-  @Rule
-  public final AppEngineRule appEngine =
+  @RegisterExtension
+  final AppEngineRule appEngine =
       AppEngineRule.builder()
           .withDatastoreAndCloudSql()
           .withTaskQueue(
@@ -96,8 +93,8 @@ public class TldFanoutActionTest {
     action.run();
   }
 
-  @Before
-  public void before() {
+  @BeforeEach
+  void beforeEach() {
     createTlds("com", "net", "org", "example");
     persistResource(Registry.get("example").asBuilder().setTldType(TldType.TEST).build());
   }
@@ -123,36 +120,36 @@ public class TldFanoutActionTest {
   }
 
   @Test
-  public void testSuccess_methodPostIsDefault() {
+  void testSuccess_methodPostIsDefault() {
     run(getParamsMap("runInEmpty", ""));
     assertTasksEnqueued(QUEUE, new TaskMatcher().method("POST"));
   }
 
   @Test
-  public void testFailure_noTlds() {
+  void testFailure_noTlds() {
     assertThrows(IllegalArgumentException.class, () -> run(getParamsMap()));
   }
 
   @Test
-  public void testSuccess_runInEmpty() {
+  void testSuccess_runInEmpty() {
     run(getParamsMap("runInEmpty", ""));
     assertTaskWithoutTld();
   }
 
   @Test
-  public void testSuccess_forEachRealTld() {
+  void testSuccess_forEachRealTld() {
     run(getParamsMap("forEachRealTld", ""));
     assertTasks("com", "net", "org");
   }
 
   @Test
-  public void testSuccess_forEachTestTld() {
+  void testSuccess_forEachTestTld() {
     run(getParamsMap("forEachTestTld", ""));
     assertTasks("example");
   }
 
   @Test
-  public void testSuccess_forEachTestTldAndForEachRealTld() {
+  void testSuccess_forEachTestTldAndForEachRealTld() {
     run(getParamsMap(
         "forEachTestTld", "",
         "forEachRealTld", ""));
@@ -160,13 +157,13 @@ public class TldFanoutActionTest {
   }
 
   @Test
-  public void testSuccess_runEverywhere() {
+  void testSuccess_runEverywhere() {
     run(getParamsMap("forEachTestTld", "", "forEachRealTld", ""));
     assertTasks("com", "net", "org", "example");
   }
 
   @Test
-  public void testSuccess_excludeRealTlds() {
+  void testSuccess_excludeRealTlds() {
     run(getParamsMap(
         "forEachRealTld", "",
         "exclude", "com,net"));
@@ -174,7 +171,7 @@ public class TldFanoutActionTest {
   }
 
   @Test
-  public void testSuccess_excludeTestTlds() {
+  void testSuccess_excludeTestTlds() {
     run(getParamsMap(
         "forEachTestTld", "",
         "exclude", "example"));
@@ -182,7 +179,7 @@ public class TldFanoutActionTest {
   }
 
   @Test
-  public void testSuccess_excludeNonexistentTlds() {
+  void testSuccess_excludeNonexistentTlds() {
     run(getParamsMap(
         "forEachTestTld", "",
         "forEachRealTld", "",
@@ -191,7 +188,7 @@ public class TldFanoutActionTest {
   }
 
   @Test
-  public void testFailure_runInEmptyAndTest() {
+  void testFailure_runInEmptyAndTest() {
     assertThrows(
         IllegalArgumentException.class,
         () ->
@@ -202,7 +199,7 @@ public class TldFanoutActionTest {
   }
 
   @Test
-  public void testFailure_runInEmptyAndReal() {
+  void testFailure_runInEmptyAndReal() {
     assertThrows(
         IllegalArgumentException.class,
         () ->
@@ -213,7 +210,7 @@ public class TldFanoutActionTest {
   }
 
   @Test
-  public void testFailure_runInEmptyAndExclude() {
+  void testFailure_runInEmptyAndExclude() {
     assertThrows(
         IllegalArgumentException.class,
         () ->
@@ -224,14 +221,14 @@ public class TldFanoutActionTest {
   }
 
   @Test
-  public void testSuccess_additionalArgsFlowThroughToPostParams() {
+  void testSuccess_additionalArgsFlowThroughToPostParams() {
     run(getParamsMap("forEachTestTld", "", "newkey", "newval"));
     assertTasksEnqueued(QUEUE,
         new TaskMatcher().url("/the/servlet").param("newkey", "newval"));
   }
 
   @Test
-  public void testSuccess_returnHttpResponse() {
+  void testSuccess_returnHttpResponse() {
     run(getParamsMap("forEachRealTld", "", "endpoint", "/the/servlet"));
 
     List<TaskStateInfo> taskList =
@@ -250,7 +247,7 @@ public class TldFanoutActionTest {
   }
 
   @Test
-  public void testSuccess_returnHttpResponse_runInEmpty() {
+  void testSuccess_returnHttpResponse_runInEmpty() {
     run(getParamsMap("runInEmpty", "", "endpoint", "/the/servlet"));
 
     List<TaskStateInfo> taskList =

core/src/test/java/google/registry/documentation/FlowDocumentationTest.java

@@ -22,13 +22,10 @@ import com.google.common.base.Joiner;
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
 
 /** Tests to ensure that generated flow documentation matches the expected documentation. */
-@RunWith(JUnit4.class)
-public class FlowDocumentationTest {
+class FlowDocumentationTest {
   private static final Path GOLDEN_MARKDOWN_FILEPATH = getProjectRoot().resolve("docs/flows.md");
 
   private static final String UPDATE_COMMAND = "./gradlew :core:flowDocsTool";
@@ -43,7 +40,7 @@ public class FlowDocumentationTest {
               "");
 
   @Test
-  public void testGeneratedMatchesGolden() throws IOException {
+  void testGeneratedMatchesGolden() throws IOException {
     // Read the markdown file.
     Path goldenMarkdownPath =
         GOLDEN_MARKDOWN_FILEPATH;

core/src/test/java/google/registry/documentation/FlowExceptionsTest.java

@@ -21,9 +21,7 @@ import com.google.common.flogger.FluentLogger;
 import google.registry.documentation.FlowDocumentation.ErrorCase;
 import java.io.IOException;
 import java.util.Set;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
 
 /**
  * Test to ensure accurate documentation of flow exceptions.
@@ -47,13 +45,12 @@ import org.junit.runners.JUnit4;
  * removing the javadoc tag.
  */
 @SuppressWarnings("javadoc")
-@RunWith(JUnit4.class)
-public class FlowExceptionsTest {
+class FlowExceptionsTest {
 
   private static final FluentLogger logger = FluentLogger.forEnclosingClass();
 
   @Test
-  public void testExceptionCorrespondence() throws IOException {
+  void testExceptionCorrespondence() throws IOException {
     DocumentationGenerator docGenerator = new DocumentationGenerator();
     Set<ErrorCase> possibleErrors = Sets.newHashSet(docGenerator.getAllErrors());
     Set<String> mismatchingFlows = Sets.newHashSet();

core/src/test/java/google/registry/documentation/MarkdownDocumentationFormatterTest.java

@@ -18,15 +18,13 @@ import static com.google.common.truth.Truth.assertThat;
 import static org.junit.Assert.assertThrows;
 
 import java.util.Arrays;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
 
 /** Test conversion of javadocs to markdown. */
-@RunWith(JUnit4.class)
-public class MarkdownDocumentationFormatterTest {
+class MarkdownDocumentationFormatterTest {
+
   @Test
-  public void testHtmlSanitization() {
+  void testHtmlSanitization() {
     assertThat(
             MarkdownDocumentationFormatter.fixHtml(
                 "First. <p>Second. &lt; &gt; &amp; &squot; &quot;"))
@@ -38,55 +36,55 @@ public class MarkdownDocumentationFormatterTest {
   }
 
   @Test
-  public void testDedents() {
-    assertThat(MarkdownDocumentationFormatter.fixHtml(
-        "First line\n\n <p>Second line.\n Third line."))
+  void testDedents() {
+    assertThat(
+            MarkdownDocumentationFormatter.fixHtml("First line\n\n <p>Second line.\n Third line."))
         .isEqualTo("First line\n\nSecond line.\nThird line.");
   }
 
   @Test
-  public void testUnknownSequences() {
+  void testUnknownSequences() {
     assertThrows(
         IllegalArgumentException.class, () -> MarkdownDocumentationFormatter.fixHtml("&blech;"));
   }
 
   @Test
-  public void testParagraphFormatting() {
+  void testParagraphFormatting() {
     String[] words = {"first", "second", "third", "really-really-long-word", "more", "stuff"};
     String formatted = MarkdownDocumentationFormatter.formatParagraph(Arrays.asList(words), 16);
     assertThat(formatted).isEqualTo("first second\nthird\nreally-really-long-word\nmore stuff\n");
   }
 
   @Test
-  public void testReflow() {
+  void testReflow() {
     String input =
         "This is the very first line.\n"
-        + "  \n"  // add a little blank space to this line just to make things interesting.
-        + "This is the second paragraph.  Aint\n"
-        + "it sweet?\n"
-        + "\n"
-        + "This is our third and final paragraph.\n"
-        + "It is multi-line and ends with no blank\n"
-        + "line.";
+            + "  \n" // add a little blank space to this line just to make things interesting.
+            + "This is the second paragraph.  Aint\n"
+            + "it sweet?\n"
+            + "\n"
+            + "This is our third and final paragraph.\n"
+            + "It is multi-line and ends with no blank\n"
+            + "line.";
 
     String expected =
         "This is the very\n"
-        + "first line.\n"
-        + "\n"
-        + "This is the\n"
-        + "second\n"
-        + "paragraph. Aint\n"
-        + "it sweet?\n"
-        + "\n"
-        + "This is our\n"
-        + "third and final\n"
-        + "paragraph. It is\n"
-        + "multi-line and\n"
-        + "ends with no\n"
-        + "blank line.\n";
+            + "first line.\n"
+            + "\n"
+            + "This is the\n"
+            + "second\n"
+            + "paragraph. Aint\n"
+            + "it sweet?\n"
+            + "\n"
+            + "This is our\n"
+            + "third and final\n"
+            + "paragraph. It is\n"
+            + "multi-line and\n"
+            + "ends with no\n"
+            + "blank line.\n";
 
-      assertThat(MarkdownDocumentationFormatter.reflow(input, 16)).isEqualTo(expected);
-    }
+    assertThat(MarkdownDocumentationFormatter.reflow(input, 16)).isEqualTo(expected);
+  }
 
-  public MarkdownDocumentationFormatterTest() {}
+  MarkdownDocumentationFormatterTest() {}
 }

core/src/test/java/google/registry/groups/DirectoryGroupsConnectionTest.java

@@ -49,16 +49,12 @@ import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import google.registry.groups.GroupsConnection.Role;
 import java.util.Set;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+/** Unit tests for {@link DirectoryGroupsConnection}. */
+class DirectoryGroupsConnectionTest {
 
-/**
- * Unit tests for {@link DirectoryGroupsConnection}.
- */
-@RunWith(JUnit4.class)
-public class DirectoryGroupsConnectionTest {
   private final Directory directory = mock(Directory.class);
   private final Groupssettings groupsSettings = mock(Groupssettings.class);
   private final Directory.Members members = mock(Directory.Members.class);
@@ -75,8 +71,8 @@ public class DirectoryGroupsConnectionTest {
   private DirectoryGroupsConnection connection;
   private Member expectedOwner = new Member();
 
-  @Before
-  public void init() throws Exception {
+  @BeforeEach
+  void beforeEach() throws Exception {
     when(directory.members()).thenReturn(members);
     when(members.insert(anyString(), any(Member.class))).thenReturn(membersInsert);
     when(members.get(anyString(), anyString())).thenReturn(membersGet);
@@ -94,12 +90,12 @@ public class DirectoryGroupsConnectionTest {
   }
 
   @Test
-  public void test_addMemberToGroup_succeeds() throws Exception {
+  void test_addMemberToGroup_succeeds() throws Exception {
     runAddMemberTest();
   }
 
   @Test
-  public void test_addMemberToGroup_isIdempotent_whenMemberAlreadyExists() throws Exception {
+  void test_addMemberToGroup_isIdempotent_whenMemberAlreadyExists() throws Exception {
     Member expected = runAddMemberTest();
     when(membersInsert.execute())
         .thenThrow(makeResponseException(SC_CONFLICT, "Member already exists."));
@@ -109,14 +105,14 @@ public class DirectoryGroupsConnectionTest {
   }
 
   @Test
-  public void test_addMemberToGroup_handlesExceptionThrownByDirectoryService() throws Exception {
+  void test_addMemberToGroup_handlesExceptionThrownByDirectoryService() throws Exception {
     when(membersInsert.execute()).thenThrow(
         makeResponseException(SC_INTERNAL_SERVER_ERROR, "Could not contact Directory server."));
     assertThrows(GoogleJsonResponseException.class, this::runAddMemberTest);
   }
 
   @Test
-  public void test_addMemberToGroup_handlesMemberKeyNotFoundException() throws Exception {
+  void test_addMemberToGroup_handlesMemberKeyNotFoundException() throws Exception {
     when(membersInsert.execute()).thenThrow(
         makeResponseException(SC_NOT_FOUND, "Resource Not Found: memberKey"));
     RuntimeException thrown =
@@ -131,7 +127,7 @@ public class DirectoryGroupsConnectionTest {
   }
 
   @Test
-  public void test_addMemberToGroup_createsGroupWhenNonexistent() throws Exception {
+  void test_addMemberToGroup_createsGroupWhenNonexistent() throws Exception {
     Member expected = new Member();
     expected.setEmail("tim@example.com");
     expected.setRole("MEMBER");
@@ -157,12 +153,12 @@ public class DirectoryGroupsConnectionTest {
   }
 
   @Test
-  public void test_createGroup_succeeds() throws Exception {
+  void test_createGroup_succeeds() throws Exception {
     runCreateGroupTest();
   }
 
   @Test
-  public void test_createGroup_isIdempotent_whenGroupAlreadyExists() throws Exception {
+  void test_createGroup_isIdempotent_whenGroupAlreadyExists() throws Exception {
     Group expected = runCreateGroupTest();
     when(groupsInsert.execute())
         .thenThrow(makeResponseException(SC_CONFLICT, "Entity already exists."));
@@ -173,14 +169,14 @@ public class DirectoryGroupsConnectionTest {
   }
 
   @Test
-  public void test_createGroup_handlesExceptionThrownByDirectoryService() throws Exception {
+  void test_createGroup_handlesExceptionThrownByDirectoryService() throws Exception {
     when(groupsInsert.execute()).thenThrow(
         makeResponseException(SC_INTERNAL_SERVER_ERROR, "Could not contact Directory server."));
     assertThrows(GoogleJsonResponseException.class, this::runCreateGroupTest);
   }
 
   @Test
-  public void test_getMembersOfGroup_succeeds() throws Exception {
+  void test_getMembersOfGroup_succeeds() throws Exception {
     Member member1 = new Member();
     member1.setEmail("john@example.com");
     Member member2 = new Member();
@@ -208,7 +204,7 @@ public class DirectoryGroupsConnectionTest {
   }
 
   @Test
-  public void test_getMembersOfNonexistentGroup_returnsEmptySet() throws Exception {
+  void test_getMembersOfNonexistentGroup_returnsEmptySet() throws Exception {
     when(members.list("nonexistent_group@fake.notreal")).thenReturn(membersList);
     when(membersList.setRoles("MEMBER")).thenReturn(membersList);
     when(membersList.execute())
@@ -217,7 +213,7 @@ public class DirectoryGroupsConnectionTest {
   }
 
   @Test
-  public void test_isMemberOfSupportGroup_userInGroup_True() throws Exception {
+  void test_isMemberOfSupportGroup_userInGroup_True() throws Exception {
     when(members.get("support@domain-registry.example", "user@example.com")).thenReturn(membersGet);
     when(membersGet.execute()).thenReturn(new Member());
     assertThat(connection.isMemberOfGroup("user@example.com", "support@domain-registry.example"))
@@ -225,7 +221,7 @@ public class DirectoryGroupsConnectionTest {
   }
 
   @Test
-  public void test_isMemberOfSupportGroup_userExistButNotInGroup_returnsFalse() throws Exception {
+  void test_isMemberOfSupportGroup_userExistButNotInGroup_returnsFalse() throws Exception {
     when(members.get("support@domain-registry.example", "user@example.com"))
         .thenThrow(makeResponseException(0, "Resource Not Found: memberKey"));
     when(membersGet.execute()).thenReturn(new Member());
@@ -234,7 +230,7 @@ public class DirectoryGroupsConnectionTest {
   }
 
   @Test
-  public void test_isMemberOfSupportGroup_userDoesntExist_returnsFalse() throws Exception {
+  void test_isMemberOfSupportGroup_userDoesntExist_returnsFalse() throws Exception {
     when(members.get("support@domain-registry.example", "user@example.com"))
         .thenThrow(makeResponseException(0, "Missing required field: memberKey"));
     when(membersGet.execute()).thenReturn(new Member());
@@ -243,7 +239,7 @@ public class DirectoryGroupsConnectionTest {
   }
 
   @Test
-  public void test_isMemberOfSupportGroup_otherError_throws() throws Exception {
+  void test_isMemberOfSupportGroup_otherError_throws() throws Exception {
     when(members.get("support@domain-registry.example", "user@example.com"))
         .thenThrow(makeResponseException(0, "some error"));
     when(membersGet.execute()).thenReturn(new Member());

core/src/test/java/google/registry/keyring/api/ComparatorKeyringTest.java

@@ -30,15 +30,12 @@ import org.bouncycastle.bcpg.PublicKeyPacket;
 import org.bouncycastle.openpgp.PGPKeyPair;
 import org.bouncycastle.openpgp.PGPPrivateKey;
 import org.bouncycastle.openpgp.PGPPublicKey;
-import org.junit.After;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 
 /** Unit tests for {@link ComparatorKeyring}. */
-@RunWith(JUnit4.class)
-public class ComparatorKeyringTest {
+class ComparatorKeyringTest {
 
   private static final String PUBLIC_KEY_FINGERPRINT = "fingerprint";
   private static final String PUBLIC_KEY_TO_STRING =
@@ -79,18 +76,18 @@ public class ComparatorKeyringTest {
 
   private final TestLogHandler testLogHandler = new TestLogHandler();
 
-  @Before
-  public void setUp() {
+  @BeforeEach
+  void beforeEach() {
     LoggerConfig.getConfig(ComparatorKeyring.class).addHandler(testLogHandler);
   }
 
-  @After
-  public void tearDown() {
+  @AfterEach
+  void afterEach() {
     LoggerConfig.getConfig(ComparatorKeyring.class).removeHandler(testLogHandler);
   }
 
   @Test
-  public void testPublicKeyToString() throws Exception {
+  void testPublicKeyToString() throws Exception {
     assertThat(
             ComparatorKeyring.stringify(
                 mockPublicKey(false, false)))
@@ -98,7 +95,7 @@ public class ComparatorKeyringTest {
   }
 
   @Test
-  public void testPublicKeyEquals() throws Exception {
+  void testPublicKeyEquals() throws Exception {
     assertThat(
             ComparatorKeyring.compare(
                 mockPublicKey(false, false),
@@ -107,7 +104,7 @@ public class ComparatorKeyringTest {
   }
 
   @Test
-  public void testPublicKeyDifferFingerprint_notEqual() throws Exception {
+  void testPublicKeyDifferFingerprint_notEqual() throws Exception {
     assertThat(
             ComparatorKeyring.compare(
                 mockPublicKey(false, false),
@@ -116,7 +113,7 @@ public class ComparatorKeyringTest {
   }
 
   @Test
-  public void testPublicKeyDifferEncoded_notEqual() throws Exception {
+  void testPublicKeyDifferEncoded_notEqual() throws Exception {
     assertThat(
             ComparatorKeyring.compare(
                 mockPublicKey(false, false),
@@ -125,7 +122,7 @@ public class ComparatorKeyringTest {
   }
 
   @Test
-  public void testPrivateKeyToString() throws Exception {
+  void testPrivateKeyToString() throws Exception {
     assertThat(
             ComparatorKeyring.stringify(
                 mockPrivateKey(false, false, false, false)))
@@ -133,7 +130,7 @@ public class ComparatorKeyringTest {
   }
 
   @Test
-  public void testPrivateKeyEquals() throws Exception {
+  void testPrivateKeyEquals() throws Exception {
     assertThat(
             ComparatorKeyring.compare(
                 mockPrivateKey(false, false, false, false),
@@ -142,7 +139,7 @@ public class ComparatorKeyringTest {
   }
 
   @Test
-  public void testPrivateKeyDifferId_notEquals() throws Exception {
+  void testPrivateKeyDifferId_notEquals() throws Exception {
     assertThat(
             ComparatorKeyring.compare(
                 mockPrivateKey(false, false, false, false),
@@ -151,7 +148,7 @@ public class ComparatorKeyringTest {
   }
 
   @Test
-  public void testPrivateKeyDifferBcpgFormat_notEquals() throws Exception {
+  void testPrivateKeyDifferBcpgFormat_notEquals() throws Exception {
     assertThat(
             ComparatorKeyring.compare(
                 mockPrivateKey(false, false, false, false),
@@ -160,7 +157,7 @@ public class ComparatorKeyringTest {
   }
 
   @Test
-  public void testPrivateKeyDifferBcpgEncoding_notEquals() throws Exception {
+  void testPrivateKeyDifferBcpgEncoding_notEquals() throws Exception {
     assertThat(
             ComparatorKeyring.compare(
                 mockPrivateKey(false, false, false, false),
@@ -169,7 +166,7 @@ public class ComparatorKeyringTest {
   }
 
   @Test
-  public void testPrivateKeyDifferPublicKeyEncoding_notEquals() throws Exception {
+  void testPrivateKeyDifferPublicKeyEncoding_notEquals() throws Exception {
     assertThat(
             ComparatorKeyring.compare(
                 mockPrivateKey(false, false, false, false),
@@ -178,7 +175,7 @@ public class ComparatorKeyringTest {
   }
 
   @Test
-  public void testKeyPairToString() throws Exception {
+  void testKeyPairToString() throws Exception {
     assertThat(
             ComparatorKeyring.stringify(
                 new PGPKeyPair(
@@ -188,7 +185,7 @@ public class ComparatorKeyringTest {
   }
 
   @Test
-  public void testKeyPairEquals() throws Exception {
+  void testKeyPairEquals() throws Exception {
     assertThat(
             ComparatorKeyring.compare(
                 new PGPKeyPair(
@@ -201,7 +198,7 @@ public class ComparatorKeyringTest {
   }
 
   @Test
-  public void testKeyPairDifferPublicKey_notEqual() throws Exception {
+  void testKeyPairDifferPublicKey_notEqual() throws Exception {
     assertThat(
             ComparatorKeyring.compare(
                 new PGPKeyPair(
@@ -214,7 +211,7 @@ public class ComparatorKeyringTest {
   }
 
   @Test
-  public void testKeyPairDifferPrivateKey_notEqual() throws Exception {
+  void testKeyPairDifferPrivateKey_notEqual() throws Exception {
     assertThat(
             ComparatorKeyring.compare(
                 new PGPKeyPair(
@@ -232,7 +229,7 @@ public class ComparatorKeyringTest {
   // We will fully test a single method just to make sure everything is "connected" correctly.
 
   @Test
-  public void testRdeSigningKey_actualThrows() throws Exception {
+  void testRdeSigningKey_actualThrows() throws Exception {
     Keyring actualKeyring = mock(Keyring.class);
     Keyring secondKeyring = mock(Keyring.class);
     PGPKeyPair keyPair =
@@ -252,7 +249,7 @@ public class ComparatorKeyringTest {
   }
 
   @Test
-  public void testRdeSigningKey_secondThrows() throws Exception {
+  void testRdeSigningKey_secondThrows() throws Exception {
     Keyring actualKeyring = mock(Keyring.class);
     Keyring secondKeyring = mock(Keyring.class);
     PGPKeyPair keyPair =
@@ -272,7 +269,7 @@ public class ComparatorKeyringTest {
   }
 
   @Test
-  public void testRdeSigningKey_bothThrow() {
+  void testRdeSigningKey_bothThrow() {
     Keyring actualKeyring = mock(Keyring.class);
     Keyring secondKeyring = mock(Keyring.class);
     when(actualKeyring.getRdeSigningKey()).thenThrow(new KeyringException("message"));
@@ -285,7 +282,7 @@ public class ComparatorKeyringTest {
   }
 
   @Test
-  public void testRdeSigningKey_same() throws Exception {
+  void testRdeSigningKey_same() throws Exception {
     Keyring actualKeyring = mock(Keyring.class);
     Keyring secondKeyring = mock(Keyring.class);
     PGPKeyPair keyPair =
@@ -306,7 +303,7 @@ public class ComparatorKeyringTest {
   }
 
   @Test
-  public void testRdeSigningKey_different() throws Exception {
+  void testRdeSigningKey_different() throws Exception {
     Keyring actualKeyring = mock(Keyring.class);
     Keyring secondKeyring = mock(Keyring.class);
     PGPKeyPair keyPair =

core/src/test/java/google/registry/keyring/kms/KmsConnectionImplTest.java

@@ -38,21 +38,20 @@ import google.registry.testing.FakeClock;
 import google.registry.testing.FakeSleeper;
 import google.registry.util.Retrier;
 import java.io.ByteArrayInputStream;
-import org.junit.Before;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
 import org.mockito.ArgumentCaptor;
 import org.mockito.Captor;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnit;
-import org.mockito.junit.MockitoRule;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.mockito.junit.jupiter.MockitoSettings;
+import org.mockito.quality.Strictness;
 
-@RunWith(JUnit4.class)
-public class KmsConnectionImplTest {
-
-  @Rule public final MockitoRule mocks = MockitoJUnit.rule();
+/** Unit tests for {@link KmsConnectionImpl}. */
+@ExtendWith(MockitoExtension.class)
+@MockitoSettings(strictness = Strictness.LENIENT)
+class KmsConnectionImplTest {
 
   @Mock private CloudKMS kms;
   @Mock private CloudKMS.Projects kmsProjects;
@@ -91,8 +90,8 @@ public class KmsConnectionImplTest {
 
   private final Retrier retrier = new Retrier(new FakeSleeper(new FakeClock()), 3);
 
-  @Before
-  public void setUp() throws Exception {
+  @BeforeEach
+  void beforeEach() throws Exception {
     when(kms.projects()).thenReturn(kmsProjects);
     when(kmsProjects.locations()).thenReturn(kmsLocations);
     when(kmsLocations.keyRings()).thenReturn(kmsKeyRings);
@@ -123,7 +122,7 @@ public class KmsConnectionImplTest {
   }
 
   @Test
-  public void test_encrypt_createsKeyRingIfNotFound() throws Exception {
+  void test_encrypt_createsKeyRingIfNotFound() throws Exception {
     when(kmsKeyRingsGet.execute()).thenThrow(createNotFoundException());
 
     new KmsConnectionImpl("foo", "bar", retrier, kms).encrypt("key", "moo".getBytes(UTF_8));
@@ -142,7 +141,7 @@ public class KmsConnectionImplTest {
   }
 
   @Test
-  public void test_encrypt_newCryptoKey() throws Exception {
+  void test_encrypt_newCryptoKey() throws Exception {
     when(kmsCryptoKeysGet.execute()).thenThrow(createNotFoundException());
 
     new KmsConnectionImpl("foo", "bar", retrier, kms).encrypt("key", "moo".getBytes(UTF_8));
@@ -163,10 +162,9 @@ public class KmsConnectionImplTest {
   }
 
   @Test
-  public void test_encrypt() throws Exception {
+  void test_encrypt() throws Exception {
     new KmsConnectionImpl("foo", "bar", retrier, kms).encrypt("key", "moo".getBytes(UTF_8));
 
-
     verify(kmsCryptoKeyVersions).create(cryptoKeyName.capture(), cryptoKeyVersion.capture());
     assertThat(cryptoKeyName.getValue())
         .isEqualTo("projects/foo/locations/global/keyRings/bar/cryptoKeys/key");
@@ -188,7 +186,7 @@ public class KmsConnectionImplTest {
   }
 
   @Test
-  public void test_decrypt() throws Exception {
+  void test_decrypt() throws Exception {
     when(kmsCryptoKeysDecrypt.execute())
         .thenReturn(new DecryptResponse().encodePlaintext("moo".getBytes(UTF_8)));
 

core/src/test/java/google/registry/mapreduce/inputs/ChildEntityInputTest.java

@@ -50,95 +50,90 @@ import java.util.Set;
 import org.joda.money.Money;
 import org.joda.time.DateTime;
 import org.joda.time.DateTimeZone;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
 
 /** Tests {@link ChildEntityInput} */
-@RunWith(JUnit4.class)
-public class ChildEntityInputTest {
+class ChildEntityInputTest {
 
   private static final DateTime now = DateTime.now(DateTimeZone.UTC);
 
-  @Rule
-  public final AppEngineRule appEngine = AppEngineRule.builder().withDatastoreAndCloudSql().build();
+  @RegisterExtension
+  final AppEngineRule appEngine = AppEngineRule.builder().withDatastoreAndCloudSql().build();
 
-  DomainBase domainA;
-  DomainBase domainB;
-  HistoryEntry domainHistoryEntryA;
-  HistoryEntry domainHistoryEntryB;
-  HistoryEntry contactHistoryEntry;
-  BillingEvent.OneTime oneTimeA;
-  BillingEvent.OneTime oneTimeB;
-  BillingEvent.Recurring recurringA;
-  BillingEvent.Recurring recurringB;
+  private DomainBase domainA;
+  private DomainBase domainB;
+  private HistoryEntry domainHistoryEntryA;
+  private HistoryEntry domainHistoryEntryB;
+  private HistoryEntry contactHistoryEntry;
+  private BillingEvent.OneTime oneTimeA;
+  private BillingEvent.OneTime oneTimeB;
+  private BillingEvent.Recurring recurringA;
+  private BillingEvent.Recurring recurringB;
 
   private void setupResources() {
     createTld("tld");
     ContactResource contact = persistEppResourceInFirstBucket(newContactResource("contact1234"));
     domainA = persistEppResourceInFirstBucket(newDomainBase("a.tld", contact));
-    domainHistoryEntryA = persistResource(
-        new HistoryEntry.Builder()
-            .setParent(domainA)
-            .setModificationTime(now)
-            .build());
-    contactHistoryEntry = persistResource(
-        new HistoryEntry.Builder()
-            .setParent(contact)
-            .setModificationTime(now)
-            .build());
-    oneTimeA = persistResource(
-        new BillingEvent.OneTime.Builder()
-            .setParent(domainHistoryEntryA)
-            .setReason(Reason.CREATE)
-            .setFlags(ImmutableSet.of(BillingEvent.Flag.ANCHOR_TENANT))
-            .setPeriodYears(2)
-            .setCost(Money.of(USD, 1))
-            .setEventTime(now)
-            .setBillingTime(now.plusDays(5))
-            .setClientId("TheRegistrar")
-            .setTargetId("a.tld")
-            .build());
-    recurringA = persistResource(
-        new BillingEvent.Recurring.Builder()
-            .setParent(domainHistoryEntryA)
-            .setReason(Reason.RENEW)
-            .setEventTime(now.plusYears(1))
-            .setRecurrenceEndTime(END_OF_TIME)
-            .setClientId("TheRegistrar")
-            .setTargetId("a.tld")
-            .build());
+    domainHistoryEntryA =
+        persistResource(
+            new HistoryEntry.Builder().setParent(domainA).setModificationTime(now).build());
+    contactHistoryEntry =
+        persistResource(
+            new HistoryEntry.Builder().setParent(contact).setModificationTime(now).build());
+    oneTimeA =
+        persistResource(
+            new BillingEvent.OneTime.Builder()
+                .setParent(domainHistoryEntryA)
+                .setReason(Reason.CREATE)
+                .setFlags(ImmutableSet.of(BillingEvent.Flag.ANCHOR_TENANT))
+                .setPeriodYears(2)
+                .setCost(Money.of(USD, 1))
+                .setEventTime(now)
+                .setBillingTime(now.plusDays(5))
+                .setClientId("TheRegistrar")
+                .setTargetId("a.tld")
+                .build());
+    recurringA =
+        persistResource(
+            new BillingEvent.Recurring.Builder()
+                .setParent(domainHistoryEntryA)
+                .setReason(Reason.RENEW)
+                .setEventTime(now.plusYears(1))
+                .setRecurrenceEndTime(END_OF_TIME)
+                .setClientId("TheRegistrar")
+                .setTargetId("a.tld")
+                .build());
   }
 
   private void setupSecondDomainBases() {
     domainB = persistEppResourceInFirstBucket(newDomainBase("b.tld"));
-    domainHistoryEntryB = persistResource(
-        new HistoryEntry.Builder()
-            .setParent(domainB)
-            .setModificationTime(now)
-            .build());
-    oneTimeB = persistResource(
-        new BillingEvent.OneTime.Builder()
-            .setParent(domainHistoryEntryA)
-            .setReason(Reason.CREATE)
-            .setFlags(ImmutableSet.of(BillingEvent.Flag.ANCHOR_TENANT))
-            .setPeriodYears(2)
-            .setCost(Money.of(USD, 1))
-            .setEventTime(now)
-            .setBillingTime(now.plusDays(5))
-            .setClientId("TheRegistrar")
-            .setTargetId("a.tld")
-            .build());
-    recurringB = persistResource(
-        new BillingEvent.Recurring.Builder()
-            .setParent(domainHistoryEntryA)
-            .setReason(Reason.RENEW)
-            .setEventTime(now.plusYears(1))
-            .setRecurrenceEndTime(END_OF_TIME)
-            .setClientId("TheRegistrar")
-            .setTargetId("a.tld")
-            .build());
+    domainHistoryEntryB =
+        persistResource(
+            new HistoryEntry.Builder().setParent(domainB).setModificationTime(now).build());
+    oneTimeB =
+        persistResource(
+            new BillingEvent.OneTime.Builder()
+                .setParent(domainHistoryEntryA)
+                .setReason(Reason.CREATE)
+                .setFlags(ImmutableSet.of(BillingEvent.Flag.ANCHOR_TENANT))
+                .setPeriodYears(2)
+                .setCost(Money.of(USD, 1))
+                .setEventTime(now)
+                .setBillingTime(now.plusDays(5))
+                .setClientId("TheRegistrar")
+                .setTargetId("a.tld")
+                .build());
+    recurringB =
+        persistResource(
+            new BillingEvent.Recurring.Builder()
+                .setParent(domainHistoryEntryA)
+                .setReason(Reason.RENEW)
+                .setEventTime(now.plusYears(1))
+                .setRecurrenceEndTime(END_OF_TIME)
+                .setClientId("TheRegistrar")
+                .setTargetId("a.tld")
+                .build());
   }
 
   @SuppressWarnings("unchecked")
@@ -154,15 +149,17 @@ public class ChildEntityInputTest {
   }
 
   @Test
-  public void testSuccess_childEntityReader_multipleParentsAndChildren() throws Exception {
+  void testSuccess_childEntityReader_multipleParentsAndChildren() throws Exception {
     setupResources();
     setupSecondDomainBases();
     Set<ImmutableObject> seen = new HashSet<>();
-    InputReader<ImmutableObject> reader = EppResourceInputs.createChildEntityInput(
-        ImmutableSet.of(EppResource.class),
-        ImmutableSet.<Class<? extends ImmutableObject>>of(
-            HistoryEntry.class, BillingEvent.OneTime.class, BillingEvent.Recurring.class))
-        .createReaders().get(0);
+    InputReader<ImmutableObject> reader =
+        EppResourceInputs.createChildEntityInput(
+                ImmutableSet.of(EppResource.class),
+                ImmutableSet.<Class<? extends ImmutableObject>>of(
+                    HistoryEntry.class, BillingEvent.OneTime.class, BillingEvent.Recurring.class))
+            .createReaders()
+            .get(0);
     reader.beginShard();
     reader.beginSlice();
     for (int i = 0; i < 8; i++) {
@@ -177,31 +174,34 @@ public class ChildEntityInputTest {
         seen.add(reader.next());
       }
     }
-    assertThat(seen).containsExactly(
-        domainHistoryEntryA,
-        domainHistoryEntryB,
-        contactHistoryEntry,
-        oneTimeA,
-        recurringA,
-        oneTimeB,
-        recurringB);
+    assertThat(seen)
+        .containsExactly(
+            domainHistoryEntryA,
+            domainHistoryEntryB,
+            contactHistoryEntry,
+            oneTimeA,
+            recurringA,
+            oneTimeB,
+            recurringB);
   }
 
   @Test
-  public void testSuccess_childEntityInput_polymorphicBaseType() {
+  void testSuccess_childEntityInput_polymorphicBaseType() {
     createChildEntityInput(ImmutableSet.of(EppResource.class), ImmutableSet.of(BillingEvent.class));
   }
 
   @Test
-  public void testSuccess_childEntityReader_multipleChildTypes() throws Exception {
+  void testSuccess_childEntityReader_multipleChildTypes() throws Exception {
     setupResources();
-    InputReader<ImmutableObject> reader = EppResourceInputs.createChildEntityInput(
-        ImmutableSet.of(EppResource.class),
-        ImmutableSet.<Class<? extends ImmutableObject>>of(
-            HistoryEntry.class, BillingEvent.OneTime.class, BillingEvent.Recurring.class))
-        .createReaders().get(0);
-    assertThat(getAllFromReader(reader)).containsExactly(
-        domainHistoryEntryA, contactHistoryEntry, oneTimeA, recurringA);
+    InputReader<ImmutableObject> reader =
+        EppResourceInputs.createChildEntityInput(
+                ImmutableSet.of(EppResource.class),
+                ImmutableSet.<Class<? extends ImmutableObject>>of(
+                    HistoryEntry.class, BillingEvent.OneTime.class, BillingEvent.Recurring.class))
+            .createReaders()
+            .get(0);
+    assertThat(getAllFromReader(reader))
+        .containsExactly(domainHistoryEntryA, contactHistoryEntry, oneTimeA, recurringA);
   }
 
   private static Set<ImmutableObject> getAllFromReader(InputReader<ImmutableObject> reader)
@@ -220,72 +220,85 @@ public class ChildEntityInputTest {
   }
 
   @Test
-  public void testSuccess_childEntityReader_filterParentTypes() throws Exception {
+  void testSuccess_childEntityReader_filterParentTypes() throws Exception {
     setupResources();
-    InputReader<ImmutableObject> reader = EppResourceInputs.createChildEntityInput(
-        ImmutableSet.<Class<? extends EppResource>>of(ContactResource.class),
-        ImmutableSet.<Class<? extends ImmutableObject>>of(
-            HistoryEntry.class, BillingEvent.OneTime.class, BillingEvent.Recurring.class))
-        .createReaders().get(0);
+    InputReader<ImmutableObject> reader =
+        EppResourceInputs.createChildEntityInput(
+                ImmutableSet.<Class<? extends EppResource>>of(ContactResource.class),
+                ImmutableSet.<Class<? extends ImmutableObject>>of(
+                    HistoryEntry.class, BillingEvent.OneTime.class, BillingEvent.Recurring.class))
+            .createReaders()
+            .get(0);
     assertThat(getAllFromReader(reader)).containsExactly(contactHistoryEntry);
   }
 
   @Test
-  public void testSuccess_childEntityReader_polymorphicChildFiltering() throws Exception {
+  void testSuccess_childEntityReader_polymorphicChildFiltering() throws Exception {
     setupResources();
-    InputReader<ImmutableObject> reader = EppResourceInputs.createChildEntityInput(
-        ImmutableSet.of(EppResource.class),
-        ImmutableSet.<Class<? extends ImmutableObject>>of(BillingEvent.OneTime.class))
-            .createReaders().get(0);
+    InputReader<ImmutableObject> reader =
+        EppResourceInputs.createChildEntityInput(
+                ImmutableSet.of(EppResource.class),
+                ImmutableSet.<Class<? extends ImmutableObject>>of(BillingEvent.OneTime.class))
+            .createReaders()
+            .get(0);
     assertThat(getAllFromReader(reader)).containsExactly(oneTimeA);
   }
 
   @Test
-  public void testSuccess_childEntityReader_polymorphicChildClass() throws Exception {
+  void testSuccess_childEntityReader_polymorphicChildClass() throws Exception {
     setupResources();
-    InputReader<ImmutableObject> reader = EppResourceInputs.createChildEntityInput(
-        ImmutableSet.of(EppResource.class),
-        ImmutableSet.<Class<? extends ImmutableObject>>of(BillingEvent.class))
-        .createReaders().get(0);
+    InputReader<ImmutableObject> reader =
+        EppResourceInputs.createChildEntityInput(
+                ImmutableSet.of(EppResource.class),
+                ImmutableSet.<Class<? extends ImmutableObject>>of(BillingEvent.class))
+            .createReaders()
+            .get(0);
     assertThat(getAllFromReader(reader)).containsExactly(oneTimeA, recurringA);
   }
 
   @Test
-  public void testSuccess_childEntityReader_noneReturned() throws Exception {
+  void testSuccess_childEntityReader_noneReturned() throws Exception {
     createTld("tld");
-    InputReader<ImmutableObject> reader = EppResourceInputs.createChildEntityInput(
-        ImmutableSet.<Class<? extends EppResource>>of(ContactResource.class),
-        ImmutableSet.<Class<? extends ImmutableObject>>of(
-            BillingEvent.OneTime.class)).createReaders().get(0);
+    InputReader<ImmutableObject> reader =
+        EppResourceInputs.createChildEntityInput(
+                ImmutableSet.<Class<? extends EppResource>>of(ContactResource.class),
+                ImmutableSet.<Class<? extends ImmutableObject>>of(BillingEvent.OneTime.class))
+            .createReaders()
+            .get(0);
     assertThat(getAllFromReader(reader)).isEmpty();
   }
 
   @Test
-  public void testSuccess_childEntityReader_readerCountMatchesBucketCount() throws Exception {
-    assertThat(EppResourceInputs.createChildEntityInput(
-        ImmutableSet.<Class<? extends EppResource>>of(DomainBase.class),
-        ImmutableSet.<Class<? extends ImmutableObject>>of(
-            BillingEvent.OneTime.class)).createReaders()).hasSize(3);
+  void testSuccess_childEntityReader_readerCountMatchesBucketCount() throws Exception {
+    assertThat(
+            EppResourceInputs.createChildEntityInput(
+                    ImmutableSet.<Class<? extends EppResource>>of(DomainBase.class),
+                    ImmutableSet.<Class<? extends ImmutableObject>>of(BillingEvent.OneTime.class))
+                .createReaders())
+        .hasSize(3);
   }
 
   @Test
-  public void testSuccess_childEntityReader_oneReaderPerBucket() throws Exception {
+  void testSuccess_childEntityReader_oneReaderPerBucket() throws Exception {
     createTld("tld");
     Set<ImmutableObject> historyEntries = new HashSet<>();
     for (int i = 1; i <= 3; i++) {
       DomainBase domain = persistSimpleResource(newDomainBase(i + ".tld"));
-      historyEntries.add(persistResource(
-          new HistoryEntry.Builder()
-              .setParent(domain)
-              .setModificationTime(now)
-              .setClientId(i + ".tld")
-              .build()));
+      historyEntries.add(
+          persistResource(
+              new HistoryEntry.Builder()
+                  .setParent(domain)
+                  .setModificationTime(now)
+                  .setClientId(i + ".tld")
+                  .build()));
       persistResource(EppResourceIndex.create(getBucketKey(i), Key.create(domain)));
     }
     Set<ImmutableObject> seen = new HashSet<>();
-    for (InputReader<ImmutableObject> reader : EppResourceInputs.createChildEntityInput(
-        ImmutableSet.<Class<? extends EppResource>>of(DomainBase.class),
-        ImmutableSet.<Class<? extends ImmutableObject>>of(HistoryEntry.class)).createReaders()) {
+    for (InputReader<ImmutableObject> reader :
+        EppResourceInputs.createChildEntityInput(
+                ImmutableSet.<Class<? extends EppResource>>of(DomainBase.class),
+                ImmutableSet.<Class<? extends ImmutableObject>>of(HistoryEntry.class))
+            .createReaders()) {
       reader.beginShard();
       reader.beginSlice();
       seen.add(reader.next());
@@ -299,7 +312,7 @@ public class ChildEntityInputTest {
   }
 
   @Test
-  public void testSuccess_childEntityReader_survivesAcrossSerialization() throws Exception {
+  void testSuccess_childEntityReader_survivesAcrossSerialization() throws Exception {
     setupResources();
     Set<ImmutableObject> seen = new HashSet<>();
     InputReader<ImmutableObject> reader =

core/src/test/java/google/registry/mapreduce/inputs/CommitLogManifestInputTest.java

@@ -30,14 +30,11 @@ import java.util.List;
 import java.util.NoSuchElementException;
 import java.util.Set;
 import org.joda.time.DateTime;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
 
 /** Unit tests for {@link CommitLogManifestInput}. */
-@RunWith(JUnit4.class)
-public final class CommitLogManifestInputTest {
+final class CommitLogManifestInputTest {
 
   private static final DateTime DATE_TIME_OLD = DateTime.parse("2015-12-19T12:00Z");
   private static final DateTime DATE_TIME_OLD2 = DateTime.parse("2016-12-19T11:59Z");
@@ -47,19 +44,18 @@ public final class CommitLogManifestInputTest {
   private static final DateTime DATE_TIME_NEW = DateTime.parse("2016-12-19T12:01Z");
   private static final DateTime DATE_TIME_NEW2 = DateTime.parse("2017-12-19T12:00Z");
 
-  @Rule
-  public final AppEngineRule appEngine = AppEngineRule.builder().withDatastoreAndCloudSql().build();
+  @RegisterExtension
+  final AppEngineRule appEngine = AppEngineRule.builder().withDatastoreAndCloudSql().build();
 
   @Test
-  public void testInputOlderThan_allFound() throws Exception {
+  void testInputOlderThan_allFound() throws Exception {
     Set<Key<CommitLogManifest>> created = new HashSet<>();
     for (int i = 1; i <= 3; i++) {
       created.add(createManifest(CommitLogBucket.getBucketKey(i), DATE_TIME_OLD));
     }
     List<Key<CommitLogManifest>> seen = new ArrayList<>();
     Input<Key<CommitLogManifest>> input = new CommitLogManifestInput(DATE_TIME_THRESHOLD);
-    for (InputReader<Key<CommitLogManifest>> reader
-        : input.createReaders()) {
+    for (InputReader<Key<CommitLogManifest>> reader : input.createReaders()) {
       reader.beginShard();
       reader.beginSlice();
       seen.add(reader.next());
@@ -73,7 +69,7 @@ public final class CommitLogManifestInputTest {
   }
 
   @Test
-  public void testInputOlderThan_skipsNew() throws Exception {
+  void testInputOlderThan_skipsNew() throws Exception {
     Set<Key<CommitLogManifest>> old = new HashSet<>();
     for (int i = 1; i <= 3; i++) {
       createManifest(CommitLogBucket.getBucketKey(i), DATE_TIME_NEW);
@@ -83,8 +79,7 @@ public final class CommitLogManifestInputTest {
     }
     List<Key<CommitLogManifest>> seen = new ArrayList<>();
     Input<Key<CommitLogManifest>> input = new CommitLogManifestInput(DATE_TIME_THRESHOLD);
-    for (InputReader<Key<CommitLogManifest>> reader
-        : input.createReaders()) {
+    for (InputReader<Key<CommitLogManifest>> reader : input.createReaders()) {
       reader.beginShard();
       reader.beginSlice();
       try {
@@ -101,7 +96,7 @@ public final class CommitLogManifestInputTest {
   }
 
   @Test
-  public void testInputAll() throws Exception {
+  void testInputAll() throws Exception {
     Set<Key<CommitLogManifest>> created = new HashSet<>();
     for (int i = 1; i <= 3; i++) {
       created.add(createManifest(CommitLogBucket.getBucketKey(i), DATE_TIME_NEW));
@@ -111,8 +106,7 @@ public final class CommitLogManifestInputTest {
     }
     List<Key<CommitLogManifest>> seen = new ArrayList<>();
     Input<Key<CommitLogManifest>> input = new CommitLogManifestInput();
-    for (InputReader<Key<CommitLogManifest>> reader
-        : input.createReaders()) {
+    for (InputReader<Key<CommitLogManifest>> reader : input.createReaders()) {
       reader.beginShard();
       reader.beginSlice();
       try {
@@ -129,8 +123,7 @@ public final class CommitLogManifestInputTest {
   }
 
   private static Key<CommitLogManifest> createManifest(
-      Key<CommitLogBucket> parent,
-      DateTime dateTime) {
+      Key<CommitLogBucket> parent, DateTime dateTime) {
     CommitLogManifest commitLogManifest = CommitLogManifest.create(parent, dateTime, null);
     DatastoreHelper.persistResource(commitLogManifest);
     return Key.create(commitLogManifest);

core/src/test/java/google/registry/mapreduce/inputs/EppResourceInputsTest.java

@@ -44,19 +44,16 @@ import java.io.ObjectOutputStream;
 import java.util.HashSet;
 import java.util.NoSuchElementException;
 import java.util.Set;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
 
 /** Tests {@link EppResourceInputs} */
-@RunWith(JUnit4.class)
-public class EppResourceInputsTest {
+class EppResourceInputsTest {
 
   private static final double EPSILON = 0.0001;
 
-  @Rule
-  public final AppEngineRule appEngine = AppEngineRule.builder().withDatastoreAndCloudSql().build();
+  @RegisterExtension
+  final AppEngineRule appEngine = AppEngineRule.builder().withDatastoreAndCloudSql().build();
 
   @SuppressWarnings("unchecked")
   private <T> T serializeAndDeserialize(T obj) throws Exception {
@@ -71,12 +68,12 @@ public class EppResourceInputsTest {
   }
 
   @Test
-  public void testSuccess_keyInputType_polymorphicBaseType() {
+  void testSuccess_keyInputType_polymorphicBaseType() {
     createKeyInput(EppResource.class);
   }
 
   @Test
-  public void testFailure_keyInputType_noInheritanceBetweenTypes_eppResource() {
+  void testFailure_keyInputType_noInheritanceBetweenTypes_eppResource() {
     IllegalArgumentException thrown =
         assertThrows(
             IllegalArgumentException.class,
@@ -85,7 +82,7 @@ public class EppResourceInputsTest {
   }
 
   @Test
-  public void testFailure_entityInputType_noInheritanceBetweenTypes_eppResource() {
+  void testFailure_entityInputType_noInheritanceBetweenTypes_eppResource() {
     IllegalArgumentException thrown =
         assertThrows(
             IllegalArgumentException.class,
@@ -94,7 +91,7 @@ public class EppResourceInputsTest {
   }
 
   @Test
-  public void testFailure_entityInputType_noInheritanceBetweenTypes_subclasses() {
+  void testFailure_entityInputType_noInheritanceBetweenTypes_subclasses() {
     IllegalArgumentException thrown =
         assertThrows(
             IllegalArgumentException.class,
@@ -103,13 +100,13 @@ public class EppResourceInputsTest {
   }
 
   @Test
-  public void testReaderCountMatchesBucketCount() throws Exception {
+  void testReaderCountMatchesBucketCount() throws Exception {
     assertThat(createKeyInput(DomainBase.class).createReaders()).hasSize(3);
     assertThat(createEntityInput(DomainBase.class).createReaders()).hasSize(3);
   }
 
   @Test
-  public void testKeyInput_oneReaderPerBucket() throws Exception {
+  void testKeyInput_oneReaderPerBucket() throws Exception {
     createTld("tld");
     Set<Key<DomainBase>> domains = new HashSet<>();
     for (int i = 1; i <= 3; i++) {
@@ -132,7 +129,7 @@ public class EppResourceInputsTest {
   }
 
   @Test
-  public void testEntityInput_oneReaderPerBucket() throws Exception {
+  void testEntityInput_oneReaderPerBucket() throws Exception {
     createTld("tld");
     Set<DomainBase> domains = new HashSet<>();
     for (int i = 1; i <= 3; i++) {
@@ -142,8 +139,7 @@ public class EppResourceInputsTest {
       persistResource(EppResourceIndex.create(getBucketKey(i), Key.create(domain)));
     }
     Set<DomainBase> seen = new HashSet<>();
-    for (InputReader<DomainBase> reader
-        : createEntityInput(DomainBase.class).createReaders()) {
+    for (InputReader<DomainBase> reader : createEntityInput(DomainBase.class).createReaders()) {
       reader.beginShard();
       reader.beginSlice();
       seen.add(reader.next());
@@ -157,7 +153,7 @@ public class EppResourceInputsTest {
   }
 
   @Test
-  public void testSuccess_keyReader_survivesAcrossSerialization() throws Exception {
+  void testSuccess_keyReader_survivesAcrossSerialization() throws Exception {
     createTld("tld");
     DomainBase domainA = persistEppResourceInFirstBucket(newDomainBase("a.tld"));
     DomainBase domainB = persistEppResourceInFirstBucket(newDomainBase("b.tld"));
@@ -181,15 +177,14 @@ public class EppResourceInputsTest {
   }
 
   @Test
-  public void testSuccess_entityReader_survivesAcrossSerialization() throws Exception {
+  void testSuccess_entityReader_survivesAcrossSerialization() throws Exception {
     createTld("tld");
     DomainBase domainA = persistEppResourceInFirstBucket(newDomainBase("a.tld"));
     DomainBase domainB = persistEppResourceInFirstBucket(newDomainBase("b.tld"));
     // Should be ignored. We'll know if it isn't because the progress counts will be off.
     persistActiveContact("contact");
     Set<DomainBase> seen = new HashSet<>();
-    InputReader<DomainBase> reader =
-        createEntityInput(DomainBase.class).createReaders().get(0);
+    InputReader<DomainBase> reader = createEntityInput(DomainBase.class).createReaders().get(0);
     reader.beginShard();
     reader.beginSlice();
     assertThat(reader.getProgress()).isWithin(EPSILON).of(0);
@@ -208,15 +203,16 @@ public class EppResourceInputsTest {
   }
 
   @Test
-  public void testSuccess_entityReader_filtersOnMultipleTypes() throws Exception {
+  void testSuccess_entityReader_filtersOnMultipleTypes() throws Exception {
     createTld("tld");
     DomainBase domain = persistEppResourceInFirstBucket(newDomainBase("a.tld"));
     HostResource host = persistEppResourceInFirstBucket(newHostResource("ns1.example.com"));
     persistEppResourceInFirstBucket(newContactResource("contact"));
     Set<EppResource> seen = new HashSet<>();
     InputReader<EppResource> reader =
-        EppResourceInputs.<EppResource>createEntityInput(
-              DomainBase.class, HostResource.class).createReaders().get(0);
+        EppResourceInputs.<EppResource>createEntityInput(DomainBase.class, HostResource.class)
+            .createReaders()
+            .get(0);
     reader.beginShard();
     reader.beginSlice();
     assertThat(reader.getProgress()).isWithin(EPSILON).of(0);
@@ -229,7 +225,7 @@ public class EppResourceInputsTest {
   }
 
   @Test
-  public void testSuccess_entityReader_noFilteringWhenUsingEppResource() throws Exception {
+  void testSuccess_entityReader_noFilteringWhenUsingEppResource() throws Exception {
     createTld("tld");
     ContactResource contact = persistEppResourceInFirstBucket(newContactResource("contact"));
     // Specify the contact since persistActiveDomain{Application} creates a hidden one.

core/src/test/java/google/registry/model/rde/RdeNamingUtilsTest.java

@@ -22,40 +22,38 @@ import static google.registry.model.rde.RdeNamingUtils.makeRydeFilename;
 import static org.junit.Assert.assertThrows;
 
 import org.joda.time.DateTime;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
 
 /** Unit tests for {@link RdeNamingUtils}. */
-@RunWith(JUnit4.class)
-public class RdeNamingUtilsTest {
+class RdeNamingUtilsTest {
+
   @Test
-  public void testMakeRydeFilename_rdeDeposit() {
+  void testMakeRydeFilename_rdeDeposit() {
     assertThat(makeRydeFilename("numbness", DateTime.parse("1984-12-18TZ"), FULL, 1, 0))
         .isEqualTo("numbness_1984-12-18_full_S1_R0");
   }
 
   @Test
-  public void testMakeRydeFilename_brdaDeposit() {
+  void testMakeRydeFilename_brdaDeposit() {
     assertThat(makeRydeFilename("dreary", DateTime.parse("2000-12-18TZ"), THIN, 1, 0))
         .isEqualTo("dreary_2000-12-18_thin_S1_R0");
   }
 
   @Test
-  public void testMakeRydeFilename_revisionNumber() {
+  void testMakeRydeFilename_revisionNumber() {
     assertThat(makeRydeFilename("wretched", DateTime.parse("2000-12-18TZ"), THIN, 1, 123))
         .isEqualTo("wretched_2000-12-18_thin_S1_R123");
   }
 
   @Test
-  public void testMakeRydeFilename_timestampNotAtTheWitchingHour_throwsIae() {
+  void testMakeRydeFilename_timestampNotAtTheWitchingHour_throwsIae() {
     assertThrows(
         IllegalArgumentException.class,
         () -> makeRydeFilename("wretched", DateTime.parse("2000-12-18T04:20Z"), THIN, 1, 0));
   }
 
   @Test
-  public void testMakePartialName() {
+  void testMakePartialName() {
     assertThat(makePartialName("unholy", DateTime.parse("2000-12-18TZ"), THIN))
         .isEqualTo("unholy_2000-12-18_thin");
   }

core/src/test/java/google/registry/model/rde/RdeRevisionTest.java

@@ -25,106 +25,95 @@ import static org.junit.Assert.assertThrows;
 import com.google.common.base.VerifyException;
 import google.registry.testing.AppEngineRule;
 import org.joda.time.DateTime;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
 
 /** Unit tests for {@link RdeRevision}. */
-@RunWith(JUnit4.class)
 public class RdeRevisionTest {
 
-  @Rule
-  public final AppEngineRule appEngine = AppEngineRule.builder().withDatastoreAndCloudSql().build();
+  @RegisterExtension
+  final AppEngineRule appEngine = AppEngineRule.builder().withDatastoreAndCloudSql().build();
 
   @Test
-  public void testGetNextRevision_objectDoesntExist_returnsZero() {
-    assertThat(getNextRevision("torment", DateTime.parse("1984-12-18TZ"), FULL))
-        .isEqualTo(0);
+  void testGetNextRevision_objectDoesntExist_returnsZero() {
+    assertThat(getNextRevision("torment", DateTime.parse("1984-12-18TZ"), FULL)).isEqualTo(0);
   }
 
   @Test
-  public void testGetNextRevision_objectExistsAtZero_returnsOne() {
+  void testGetNextRevision_objectExistsAtZero_returnsOne() {
     save("sorrow", DateTime.parse("1984-12-18TZ"), FULL, 0);
-    assertThat(getNextRevision("sorrow", DateTime.parse("1984-12-18TZ"), FULL))
-        .isEqualTo(1);
+    assertThat(getNextRevision("sorrow", DateTime.parse("1984-12-18TZ"), FULL)).isEqualTo(1);
   }
 
   @Test
-  public void testSaveRevision_objectDoesntExist_newRevisionIsZero_nextRevIsOne() {
+  void testSaveRevision_objectDoesntExist_newRevisionIsZero_nextRevIsOne() {
     tm().transact(() -> saveRevision("despondency", DateTime.parse("1984-12-18TZ"), FULL, 0));
-    tm()
-        .transact(
+    tm().transact(
             () ->
                 assertThat(getNextRevision("despondency", DateTime.parse("1984-12-18TZ"), FULL))
                     .isEqualTo(1));
   }
 
   @Test
-  public void testSaveRevision_objectDoesntExist_newRevisionIsOne_throwsVe() {
+  void testSaveRevision_objectDoesntExist_newRevisionIsOne_throwsVe() {
     VerifyException thrown =
         assertThrows(
             VerifyException.class,
             () ->
-                tm()
-                    .transact(
+                tm().transact(
                         () ->
                             saveRevision("despondency", DateTime.parse("1984-12-18TZ"), FULL, 1)));
     assertThat(thrown).hasMessageThat().contains("object missing");
   }
 
   @Test
-  public void testSaveRevision_objectExistsAtZero_newRevisionIsZero_throwsVe() {
+  void testSaveRevision_objectExistsAtZero_newRevisionIsZero_throwsVe() {
     save("melancholy", DateTime.parse("1984-12-18TZ"), FULL, 0);
     VerifyException thrown =
         assertThrows(
             VerifyException.class,
             () ->
-                tm()
-                    .transact(
+                tm().transact(
                         () -> saveRevision("melancholy", DateTime.parse("1984-12-18TZ"), FULL, 0)));
     assertThat(thrown).hasMessageThat().contains("object already created");
   }
 
   @Test
-  public void testSaveRevision_objectExistsAtZero_newRevisionIsOne_nextRevIsTwo() {
+  void testSaveRevision_objectExistsAtZero_newRevisionIsOne_nextRevIsTwo() {
     save("melancholy", DateTime.parse("1984-12-18TZ"), FULL, 0);
     tm().transact(() -> saveRevision("melancholy", DateTime.parse("1984-12-18TZ"), FULL, 1));
-    tm()
-        .transact(
+    tm().transact(
             () ->
                 assertThat(getNextRevision("melancholy", DateTime.parse("1984-12-18TZ"), FULL))
                     .isEqualTo(2));
   }
 
   @Test
-  public void testSaveRevision_objectExistsAtZero_newRevisionIsTwo_throwsVe() {
+  void testSaveRevision_objectExistsAtZero_newRevisionIsTwo_throwsVe() {
     save("melancholy", DateTime.parse("1984-12-18TZ"), FULL, 0);
     VerifyException thrown =
         assertThrows(
             VerifyException.class,
             () ->
-                tm()
-                    .transact(
+                tm().transact(
                         () -> saveRevision("melancholy", DateTime.parse("1984-12-18TZ"), FULL, 2)));
     assertThat(thrown).hasMessageThat().contains("should be at 1 ");
   }
 
   @Test
-  public void testSaveRevision_negativeRevision_throwsIae() {
+  void testSaveRevision_negativeRevision_throwsIae() {
     IllegalArgumentException thrown =
         assertThrows(
             IllegalArgumentException.class,
             () ->
-                tm()
-                    .transact(
+                tm().transact(
                         () ->
                             saveRevision("melancholy", DateTime.parse("1984-12-18TZ"), FULL, -1)));
     assertThat(thrown).hasMessageThat().contains("Negative revision");
   }
 
   @Test
-  public void testSaveRevision_callerNotInTransaction_throwsIse() {
+  void testSaveRevision_callerNotInTransaction_throwsIse() {
     IllegalStateException thrown =
         assertThrows(
             IllegalStateException.class,

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

@@ -24,30 +24,27 @@ import static org.junit.Assert.assertThrows;
 import com.google.common.net.InternetDomainName;
 import google.registry.model.registry.Registry.TldType;
 import google.registry.testing.AppEngineRule;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
 
 /** Unit tests for {@link Registries}. */
-@RunWith(JUnit4.class)
-public class RegistriesTest {
+class RegistriesTest {
 
-  @Rule
-  public final AppEngineRule appEngine = AppEngineRule.builder().withDatastoreAndCloudSql().build();
+  @RegisterExtension
+  final AppEngineRule appEngine = AppEngineRule.builder().withDatastoreAndCloudSql().build();
 
   private void initTestTlds() {
     createTlds("foo", "a.b.c"); // Test a multipart tld.
   }
 
   @Test
-  public void testGetTlds() {
+  void testGetTlds() {
     initTestTlds();
     assertThat(Registries.getTlds()).containsExactly("foo", "a.b.c");
   }
 
   @Test
-  public void test_getTldEntities() {
+  void test_getTldEntities() {
     initTestTlds();
     persistResource(newRegistry("testtld", "TESTTLD").asBuilder().setTldType(TldType.TEST).build());
     assertThat(Registries.getTldEntitiesOfType(TldType.REAL))
@@ -57,25 +54,25 @@ public class RegistriesTest {
   }
 
   @Test
-  public void testGetTlds_withNoRegistriesPersisted_returnsEmptySet() {
+  void testGetTlds_withNoRegistriesPersisted_returnsEmptySet() {
     assertThat(Registries.getTlds()).isEmpty();
   }
 
   @Test
-  public void testAssertTldExists_doesExist() {
+  void testAssertTldExists_doesExist() {
     initTestTlds();
     Registries.assertTldExists("foo");
     Registries.assertTldExists("a.b.c");
   }
 
   @Test
-  public void testAssertTldExists_doesntExist() {
+  void testAssertTldExists_doesntExist() {
     initTestTlds();
     assertThrows(IllegalArgumentException.class, () -> Registries.assertTldExists("baz"));
   }
 
   @Test
-  public void testFindTldForName() {
+  void testFindTldForName() {
     initTestTlds();
     assertThat(Registries.findTldForName(InternetDomainName.from("example.foo")).get().toString())
         .isEqualTo("foo");

core/src/test/java/google/registry/model/registry/label/GenrulePremiumListTest.java

@@ -24,23 +24,20 @@ import com.google.common.reflect.ClassPath.ResourceInfo;
 import google.registry.testing.AppEngineRule;
 import java.net.URL;
 import java.util.List;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
 
 /** Presubmit tests for {@link PremiumList} configuration files. */
-@RunWith(JUnit4.class)
-public class GenrulePremiumListTest {
+class GenrulePremiumListTest {
 
   private static final FluentLogger logger = FluentLogger.forEnclosingClass();
   private static final String LISTS_DIRECTORY = "google/registry/config/files/premium/";
 
-  @Rule
-  public final AppEngineRule appEngine = AppEngineRule.builder().withDatastoreAndCloudSql().build();
+  @RegisterExtension
+  final AppEngineRule appEngine = AppEngineRule.builder().withDatastoreAndCloudSql().build();
 
   @Test
-  public void testParse_allPremiumLists() throws Exception {
+  void testParse_allPremiumLists() throws Exception {
     ClassPath classpath = ClassPath.from(getClass().getClassLoader());
     int numParsed = 0;
     for (ResourceInfo resource : classpath.getResources()) {

core/src/test/java/google/registry/model/registry/label/GenruleReservedListTest.java

@@ -24,23 +24,20 @@ import com.google.common.reflect.ClassPath.ResourceInfo;
 import google.registry.testing.AppEngineRule;
 import java.net.URL;
 import java.util.List;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
 
 /** Presubmit tests for {@link ReservedList} configuration files. */
-@RunWith(JUnit4.class)
-public class GenruleReservedListTest {
+class GenruleReservedListTest {
 
   private static final FluentLogger logger = FluentLogger.forEnclosingClass();
   private static final String LISTS_DIRECTORY = "google/registry/config/files/reserved/";
 
-  @Rule
-  public final AppEngineRule appEngine = AppEngineRule.builder().withDatastoreAndCloudSql().build();
+  @RegisterExtension
+  final AppEngineRule appEngine = AppEngineRule.builder().withDatastoreAndCloudSql().build();
 
   @Test
-  public void testParse_allReservedLists() throws Exception {
+  void testParse_allReservedLists() throws Exception {
     ClassPath classpath = ClassPath.from(getClass().getClassLoader());
     int numParsed = 0;
     for (ResourceInfo resource : classpath.getResources()) {

core/src/test/java/google/registry/model/registry/label/ReservedListTest.java

@@ -39,26 +39,22 @@ import google.registry.testing.AppEngineRule;
 import google.registry.testing.FakeClock;
 import google.registry.testing.InjectRule;
 import org.joda.time.DateTime;
-import org.junit.Before;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
 
 /** Unit tests for {@link ReservedList}. */
-@RunWith(JUnit4.class)
-public class ReservedListTest {
+class ReservedListTest {
 
-  @Rule
-  public final InjectRule inject = new InjectRule();
+  @RegisterExtension final InjectRule inject = new InjectRule();
 
-  @Rule
-  public final AppEngineRule appEngine = AppEngineRule.builder().withDatastoreAndCloudSql().build();
+  @RegisterExtension
+  final AppEngineRule appEngine = AppEngineRule.builder().withDatastoreAndCloudSql().build();
 
-  FakeClock clock = new FakeClock(DateTime.parse("2010-01-01T10:00:00Z"));
+  private FakeClock clock = new FakeClock(DateTime.parse("2010-01-01T10:00:00Z"));
 
-  @Before
-  public void before() {
+  @BeforeEach
+  void beforeEach() {
     inject.setStaticField(Ofy.class, "clock", clock);
     createTld("tld");
     reservedListChecks.reset();
@@ -79,7 +75,7 @@ public class ReservedListTest {
   }
 
   @Test
-  public void testGetReservationTypes_allLabelsAreUnreserved_withNoReservedLists() {
+  void testGetReservationTypes_allLabelsAreUnreserved_withNoReservedLists() {
     assertThat(Registry.get("tld").getReservedLists()).isEmpty();
     assertThat(getReservationTypes("doodle", "tld")).isEmpty();
     assertThat(getReservationTypes("access", "tld")).isEmpty();
@@ -88,13 +84,13 @@ public class ReservedListTest {
   }
 
   @Test
-  public void testZeroReservedLists_doesNotCauseError() {
+  void testZeroReservedLists_doesNotCauseError() {
     assertThat(getReservationTypes("doodle", "tld")).isEmpty();
     verifyUnreservedCheckCount(1);
   }
 
   @Test
-  public void testGetReservationTypes_twoLetterCodesAreAvailable() {
+  void testGetReservationTypes_twoLetterCodesAreAvailable() {
     for (String sld : ImmutableList.of("aa", "az", "zz", "91", "1n", "j5")) {
       assertThat(getReservationTypes(sld, "tld")).isEmpty();
     }
@@ -102,7 +98,7 @@ public class ReservedListTest {
   }
 
   @Test
-  public void testGetReservationTypes_singleCharacterDomainsAreAllowed() {
+  void testGetReservationTypes_singleCharacterDomainsAreAllowed() {
     // This isn't quite exhaustive but it's close.
     for (char c = 'a'; c <= 'z'; c++) {
       assertThat(getReservationTypes("" + c, "tld")).isEmpty();
@@ -111,7 +107,7 @@ public class ReservedListTest {
   }
 
   @Test
-  public void testGetReservationTypes_concatsMultipleListsCorrectly() {
+  void testGetReservationTypes_concatsMultipleListsCorrectly() {
     ReservedList rl1 = persistReservedList(
         "reserved1",
         "lol,FULLY_BLOCKED # yup",
@@ -153,7 +149,7 @@ public class ReservedListTest {
   }
 
   @Test
-  public void testGetReservationTypes_returnsAllReservationTypesFromMultipleListsForTheSameLabel() {
+  void testGetReservationTypes_returnsAllReservationTypesFromMultipleListsForTheSameLabel() {
     ReservedList rl1 =
         persistReservedList("reserved1", "lol,NAME_COLLISION # yup", "cat,FULLY_BLOCKED");
     ReservedList rl2 =
@@ -167,9 +163,8 @@ public class ReservedListTest {
     assertThat(getReservationTypes("snowcrash", "tld")).containsExactly(FULLY_BLOCKED);
   }
 
-
   @Test
-  public void testGetReservationTypes_worksAfterReservedListRemovedUsingSet() {
+  void testGetReservationTypes_worksAfterReservedListRemovedUsingSet() {
     ReservedList rl1 = persistReservedList(
         "reserved1", "lol,FULLY_BLOCKED", "cat,FULLY_BLOCKED");
     ReservedList rl2 = persistReservedList(
@@ -202,7 +197,7 @@ public class ReservedListTest {
   }
 
   @Test
-  public void testGetReservationTypes_combinesMultipleLists() {
+  void testGetReservationTypes_combinesMultipleLists() {
     ReservedList rl1 = persistReservedList(
         "reserved1", "lol,NAME_COLLISION", "roflcopter,ALLOWED_IN_SUNRISE");
     ReservedList rl2 = persistReservedList("reserved2", "lol,FULLY_BLOCKED");
@@ -233,7 +228,7 @@ public class ReservedListTest {
   }
 
   @Test
-  public void testSave() {
+  void testSave() {
     ReservedList rl = persistReservedList("tld-reserved", "lol,FULLY_BLOCKED # yup");
     createTld("tld");
     persistResource(Registry.get("tld").asBuilder().setReservedLists(rl).build());
@@ -241,7 +236,7 @@ public class ReservedListTest {
   }
 
   @Test
-  public void testSave_commentsArePersistedCorrectly() {
+  void testSave_commentsArePersistedCorrectly() {
     ReservedList reservedList = persistReservedList(
         "reserved",
         "trombone,FULLY_BLOCKED  # yup",
@@ -266,20 +261,20 @@ public class ReservedListTest {
   }
 
   @Test
-  public void testIsInUse_returnsTrueWhenInUse() {
+  void testIsInUse_returnsTrueWhenInUse() {
     ReservedList rl = persistReservedList("reserved", "trombone,FULLY_BLOCKED");
     persistResource(Registry.get("tld").asBuilder().setReservedLists(ImmutableSet.of(rl)).build());
     assertThat(rl.isInUse()).isTrue();
   }
 
   @Test
-  public void testIsInUse_returnsFalseWhenNotInUse() {
+  void testIsInUse_returnsFalseWhenNotInUse() {
     ReservedList rl = persistReservedList("reserved", "trombone,FULLY_BLOCKED");
     assertThat(rl.isInUse()).isFalse();
   }
 
   @Test
-  public void testSetFromInputLines() {
+  void testSetFromInputLines() {
     ReservedList reservedList = persistReservedList("reserved", "trombone,FULLY_BLOCKED");
     assertThat(ReservedList.get("reserved").get().getReservedListEntries()).hasSize(1);
     reservedList = reservedList.asBuilder()
@@ -290,7 +285,7 @@ public class ReservedListTest {
   }
 
   @Test
-  public void testAsBuilderReturnsIdenticalReservedList() {
+  void testAsBuilderReturnsIdenticalReservedList() {
     ReservedList original = persistReservedList("tld-reserved-cloning", "trombone,FULLY_BLOCKED");
     ReservedList clone = original.asBuilder().build();
     assertThat(clone.getName()).isEqualTo("tld-reserved-cloning");
@@ -301,7 +296,7 @@ public class ReservedListTest {
   }
 
   @Test
-  public void testSave_badSyntax() {
+  void testSave_badSyntax() {
     IllegalArgumentException thrown =
         assertThrows(
             IllegalArgumentException.class,
@@ -310,13 +305,13 @@ public class ReservedListTest {
   }
 
   @Test
-  public void testSave_badReservationType() {
+  void testSave_badReservationType() {
     assertThrows(
         IllegalArgumentException.class, () -> persistReservedList("tld", "lol,FULLY_BLOCKZ # yup"));
   }
 
   @Test
-  public void testParse_cannotIncludeDuplicateLabels() {
+  void testParse_cannotIncludeDuplicateLabels() {
     ReservedList rl = new ReservedList.Builder().setName("blah").build();
     IllegalStateException thrown =
         assertThrows(
@@ -336,7 +331,7 @@ public class ReservedListTest {
   }
 
   @Test
-  public void testValidation_labelMustBeLowercase() {
+  void testValidation_labelMustBeLowercase() {
     Exception e =
         assertThrows(
             IllegalArgumentException.class,
@@ -345,7 +340,7 @@ public class ReservedListTest {
   }
 
   @Test
-  public void testValidation_labelMustBePunyCoded() {
+  void testValidation_labelMustBePunyCoded() {
     Exception e =
         assertThrows(
             IllegalArgumentException.class,

core/src/test/java/google/registry/module/backend/BackendRequestComponentTest.java

@@ -19,23 +19,20 @@ import static com.google.common.truth.Truth.assertThat;
 import google.registry.request.Action;
 import google.registry.request.RouterDisplayHelper;
 import google.registry.testing.GoldenFileTestHelper;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
 
 /** Unit tests for {@link BackendRequestComponent}. */
-@RunWith(JUnit4.class)
-public class BackendRequestComponentTest {
+class BackendRequestComponentTest {
 
   @Test
-  public void testRoutingMap() {
+  void testRoutingMap() {
     GoldenFileTestHelper.assertThatRoutesFromComponent(BackendRequestComponent.class)
         .describedAs("backend routing map")
         .isEqualToGolden(BackendRequestComponentTest.class, "backend_routing.txt");
   }
 
   @Test
-  public void testRoutingService() {
+  void testRoutingService() {
     assertThat(
             RouterDisplayHelper.extractHumanReadableRoutesWithWrongService(
                 BackendRequestComponent.class, Action.Service.BACKEND))

core/src/test/java/google/registry/module/backend/BackendServletTest.java

@@ -21,24 +21,21 @@ import static org.mockito.Mockito.when;
 import google.registry.testing.AppEngineRule;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
 
 /** Unit tests for {@link BackendServlet}. */
-@RunWith(JUnit4.class)
-public class BackendServletTest {
+class BackendServletTest {
 
-  @Rule
-  public final AppEngineRule appEngine =
+  @RegisterExtension
+  final AppEngineRule appEngine =
       AppEngineRule.builder().withDatastoreAndCloudSql().withLocalModules().build();
 
   private final HttpServletRequest req = mock(HttpServletRequest.class);
   private final HttpServletResponse rsp = mock(HttpServletResponse.class);
 
   @Test
-  public void testService_unknownPath_returnsNotFound() throws Exception {
+  void testService_unknownPath_returnsNotFound() throws Exception {
     when(req.getMethod()).thenReturn("GET");
     when(req.getRequestURI()).thenReturn("/lol");
     new BackendServlet().service(req, rsp);

core/src/test/java/google/registry/module/frontend/FrontendRequestComponentTest.java

@@ -19,23 +19,20 @@ import static com.google.common.truth.Truth.assertThat;
 import google.registry.request.Action;
 import google.registry.request.RouterDisplayHelper;
 import google.registry.testing.GoldenFileTestHelper;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
 
 /** Unit tests for {@link FrontendRequestComponent}. */
-@RunWith(JUnit4.class)
-public class FrontendRequestComponentTest {
+class FrontendRequestComponentTest {
 
   @Test
-  public void testRoutingMap() {
+  void testRoutingMap() {
     GoldenFileTestHelper.assertThatRoutesFromComponent(FrontendRequestComponent.class)
         .describedAs("frontend routing map")
         .isEqualToGolden(FrontendRequestComponentTest.class, "frontend_routing.txt");
   }
 
   @Test
-  public void testRoutingService() {
+  void testRoutingService() {
     assertThat(
             RouterDisplayHelper.extractHumanReadableRoutesWithWrongService(
                 FrontendRequestComponent.class, Action.Service.DEFAULT))

core/src/test/java/google/registry/module/frontend/FrontendServletTest.java

@@ -21,24 +21,21 @@ import static org.mockito.Mockito.when;
 import google.registry.testing.AppEngineRule;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
 
 /** Unit tests for {@link FrontendServlet}. */
-@RunWith(JUnit4.class)
-public class FrontendServletTest {
+class FrontendServletTest {
 
-  @Rule
-  public final AppEngineRule appEngine =
+  @RegisterExtension
+  final AppEngineRule appEngine =
       AppEngineRule.builder().withDatastoreAndCloudSql().withLocalModules().build();
 
   private final HttpServletRequest req = mock(HttpServletRequest.class);
   private final HttpServletResponse rsp = mock(HttpServletResponse.class);
 
   @Test
-  public void testService_unknownPath_returnNotFound() throws Exception {
+  void testService_unknownPath_returnNotFound() throws Exception {
     when(req.getMethod()).thenReturn("GET");
     when(req.getRequestURI()).thenReturn("/lol");
     new FrontendServlet().service(req, rsp);

core/src/test/java/google/registry/module/pubapi/PubApiRequestComponentTest.java

@@ -19,23 +19,20 @@ import static com.google.common.truth.Truth.assertThat;
 import google.registry.request.Action;
 import google.registry.request.RouterDisplayHelper;
 import google.registry.testing.GoldenFileTestHelper;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
 
 /** Unit tests for {@link PubApiRequestComponent}. */
-@RunWith(JUnit4.class)
-public class PubApiRequestComponentTest {
+class PubApiRequestComponentTest {
 
   @Test
-  public void testRoutingMap() {
+  void testRoutingMap() {
     GoldenFileTestHelper.assertThatRoutesFromComponent(PubApiRequestComponent.class)
         .describedAs("pubapi routing map")
         .isEqualToGolden(PubApiRequestComponentTest.class, "pubapi_routing.txt");
   }
 
   @Test
-  public void testRoutingService() {
+  void testRoutingService() {
     assertThat(
             RouterDisplayHelper.extractHumanReadableRoutesWithWrongService(
                 PubApiRequestComponent.class, Action.Service.PUBAPI))

core/src/test/java/google/registry/module/pubapi/PubApiServletTest.java

@@ -21,24 +21,21 @@ import static org.mockito.Mockito.when;
 import google.registry.testing.AppEngineRule;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
 
 /** Unit tests for {@link PubApiServlet}. */
-@RunWith(JUnit4.class)
-public class PubApiServletTest {
+class PubApiServletTest {
 
-  @Rule
-  public final AppEngineRule appEngine =
+  @RegisterExtension
+  final AppEngineRule appEngine =
       AppEngineRule.builder().withDatastoreAndCloudSql().withLocalModules().build();
 
   private final HttpServletRequest req = mock(HttpServletRequest.class);
   private final HttpServletResponse rsp = mock(HttpServletResponse.class);
 
   @Test
-  public void testService_unknownPath_returnNotFound() throws Exception {
+  void testService_unknownPath_returnNotFound() throws Exception {
     when(req.getMethod()).thenReturn("GET");
     when(req.getRequestURI()).thenReturn("/lol");
     new PubApiServlet().service(req, rsp);

core/src/test/java/google/registry/module/tools/ToolsRequestComponentTest.java

@@ -19,23 +19,20 @@ import static com.google.common.truth.Truth.assertThat;
 import google.registry.request.Action;
 import google.registry.request.RouterDisplayHelper;
 import google.registry.testing.GoldenFileTestHelper;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
 
 /** Unit tests for {@link ToolsRequestComponent}. */
-@RunWith(JUnit4.class)
-public class ToolsRequestComponentTest {
+class ToolsRequestComponentTest {
 
   @Test
-  public void testRoutingMap() {
+  void testRoutingMap() {
     GoldenFileTestHelper.assertThatRoutesFromComponent(ToolsRequestComponent.class)
         .describedAs("tools routing map")
         .isEqualToGolden(ToolsRequestComponentTest.class, "tools_routing.txt");
   }
 
   @Test
-  public void testRoutingService() {
+  void testRoutingService() {
     assertThat(
             RouterDisplayHelper.extractHumanReadableRoutesWithWrongService(
                 ToolsRequestComponent.class, Action.Service.TOOLS))

core/src/test/java/google/registry/module/tools/ToolsServletTest.java

@@ -20,19 +20,16 @@ import static org.mockito.Mockito.when;
 
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
 
 /** Unit tests for {@link ToolsServlet}. */
-@RunWith(JUnit4.class)
-public class ToolsServletTest {
+class ToolsServletTest {
 
   private final HttpServletRequest req = mock(HttpServletRequest.class);
   private final HttpServletResponse rsp = mock(HttpServletResponse.class);
 
   @Test
-  public void testService_unknownPath_returnsNotFound() throws Exception {
+  void testService_unknownPath_returnsNotFound() throws Exception {
     when(req.getMethod()).thenReturn("GET");
     when(req.getRequestURI()).thenReturn("/lol");
     new ToolsServlet().service(req, rsp);

core/src/test/java/google/registry/monitoring/whitebox/CheckApiMetricTest.java

@@ -19,26 +19,23 @@ import static com.google.common.truth.Truth.assertThat;
 import google.registry.monitoring.whitebox.CheckApiMetric.Status;
 import google.registry.testing.FakeClock;
 import org.joda.time.DateTime;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 
 /** Unit tests for {@link CheckApiMetric}. */
-@RunWith(JUnit4.class)
-public class CheckApiMetricTest {
+class CheckApiMetricTest {
   private static final DateTime START_TIME = DateTime.parse("2000-01-01T00:00:00.0Z");
 
   private final FakeClock clock = new FakeClock(START_TIME);
   private CheckApiMetric.Builder metricBuilder;
 
-  @Before
-  public void setup() {
+  @BeforeEach
+  void beforeEach() {
     metricBuilder = CheckApiMetric.builder(clock);
   }
 
   @Test
-  public void testSuccess_timestampsAreSet() {
+  void testSuccess_timestampsAreSet() {
     clock.advanceOneMilli();
     CheckApiMetric metric = metricBuilder.status(Status.SUCCESS).build();
 

core/src/test/java/google/registry/monitoring/whitebox/EppMetricTest.java

@@ -21,20 +21,17 @@ import static google.registry.testing.DatastoreHelper.createTlds;
 import com.google.common.collect.ImmutableSet;
 import google.registry.testing.AppEngineRule;
 import google.registry.testing.FakeClock;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
 
 /** Unit tests for {@link EppMetric}. */
-@RunWith(JUnit4.class)
-public class EppMetricTest {
+class EppMetricTest {
 
-  @Rule
-  public final AppEngineRule appEngine = AppEngineRule.builder().withDatastoreAndCloudSql().build();
+  @RegisterExtension
+  final AppEngineRule appEngine = AppEngineRule.builder().withDatastoreAndCloudSql().build();
 
   @Test
-  public void test_invalidTld_isRecordedAsInvalid() {
+  void test_invalidTld_isRecordedAsInvalid() {
     EppMetric metric =
         EppMetric.builderForRequest(new FakeClock())
             .setTlds(ImmutableSet.of("notarealtld"))
@@ -43,7 +40,7 @@ public class EppMetricTest {
   }
 
   @Test
-  public void test_validTld_isRecorded() {
+  void test_validTld_isRecorded() {
     createTld("example");
     EppMetric metric =
         EppMetric.builderForRequest(new FakeClock()).setTlds(ImmutableSet.of("example")).build();
@@ -51,7 +48,7 @@ public class EppMetricTest {
   }
 
   @Test
-  public void test_multipleTlds_areRecordedAsVarious() {
+  void test_multipleTlds_areRecordedAsVarious() {
     createTlds("foo", "bar");
     EppMetric metric =
         EppMetric.builderForRequest(new FakeClock())
@@ -61,7 +58,7 @@ public class EppMetricTest {
   }
 
   @Test
-  public void test_zeroTlds_areRecordedAsAbsent() {
+  void test_zeroTlds_areRecordedAsAbsent() {
     EppMetric metric =
         EppMetric.builderForRequest(new FakeClock()).setTlds(ImmutableSet.of()).build();
     assertThat(metric.getTld()).isEmpty();

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

@@ -21,40 +21,42 @@ import java.io.File;
 import java.io.IOException;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
+import java.nio.file.Path;
 import javax.persistence.Entity;
 import javax.persistence.Id;
 import org.joda.money.CurrencyUnit;
-import org.junit.BeforeClass;
-import org.junit.ClassRule;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.rules.TemporaryFolder;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
 import org.testcontainers.containers.PostgreSQLContainer;
+import org.testcontainers.junit.jupiter.Container;
+import org.testcontainers.junit.jupiter.Testcontainers;
 
 /** Unit tests for {@link HibernateSchemaExporter}. */
-@RunWith(JUnit4.class)
-public class HibernateSchemaExporterTest {
-  @ClassRule
-  public static final PostgreSQLContainer database =
+@Testcontainers
+class HibernateSchemaExporterTest {
+
+  @Container
+  private static final PostgreSQLContainer database =
       new PostgreSQLContainer(NomulusPostgreSql.getDockerTag());
 
   private static HibernateSchemaExporter exporter;
 
-  @Rule public final TemporaryFolder tempFolder = new TemporaryFolder();
+  @SuppressWarnings("WeakerAccess")
+  @TempDir
+  Path tmpDir;
 
-  @BeforeClass
-  public static void init() {
+  @BeforeAll
+  static void beforeAll() {
     exporter =
         HibernateSchemaExporter.create(
             database.getJdbcUrl(), database.getUsername(), database.getPassword());
   }
 
   @Test
-  public void export_succeeds() throws IOException {
-    File sqlFile = tempFolder.newFile();
-    exporter.export(ImmutableList.of(TestEntity.class), sqlFile);
+  void export_succeeds() throws IOException {
+    File sqlFile = Files.createFile(tmpDir.resolve("tempfile.dat")).toFile();
+    exporter.export(ImmutableList.of(HibernateSchemaTestEntity.class), sqlFile);
     assertThat(Files.readAllBytes(sqlFile.toPath()))
         .isEqualTo(
             ("\n"
@@ -67,7 +69,7 @@ public class HibernateSchemaExporterTest {
   }
 
   @Entity(name = "TestEntity") // Override entity name to avoid the nested class reference.
-  private static class TestEntity {
+  private static class HibernateSchemaTestEntity {
     @Id String name;
 
     CurrencyUnit cu;

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

@@ -16,26 +16,20 @@ package google.registry.persistence;
 
 import static com.google.common.collect.ImmutableList.toImmutableList;
 import static com.google.common.collect.ImmutableSet.toImmutableSet;
+import static com.google.common.truth.Truth.assertWithMessage;
 
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
-import com.google.common.truth.Expect;
 import java.util.Collections;
 import javax.persistence.AttributeConverter;
 import javax.persistence.Entity;
-import org.junit.ClassRule;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
 
 /** Unit tests to verify persistence.xml is valid. */
-@RunWith(JUnit4.class)
-public class PersistenceXmlTest {
-
-  @ClassRule public static final Expect expect = Expect.create();
+class PersistenceXmlTest {
 
   @Test
-  public void verifyClassTags_containOnlyRequiredClasses() {
+  void verifyClassTags_containOnlyRequiredClasses() {
     ImmutableList<Class> managedClassed = PersistenceXmlUtility.getManagedClasses();
 
     ImmutableList<Class> unnecessaryClasses =
@@ -51,13 +45,11 @@ public class PersistenceXmlTest {
             .filter(clazz -> Collections.frequency(managedClassed, clazz) > 1)
             .collect(toImmutableSet());
 
-    expect
-        .withMessage("Found duplicate <class> tags defined in persistence.xml.")
+    assertWithMessage("Found duplicate <class> tags defined in persistence.xml.")
         .that(duplicateClasses)
         .isEmpty();
 
-    expect
-        .withMessage(
+    assertWithMessage(
             "Found unnecessary <class> tags defined in persistence.xml. Only entity class and"
                 + " implementation of AttributeConverter are required to be added in"
                 + " persistence.xml.")

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

@@ -18,25 +18,21 @@ import static com.google.common.truth.Truth.assertThat;
 import com.googlecode.objectify.Key;
 import google.registry.testing.AppEngineRule;
 import google.registry.testing.TestObject;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
 
-@RunWith(JUnit4.class)
-public class VKeyTest {
+/** Unit tests for {@link VKey}. */
+class VKeyTest {
 
-  @Rule
-  public final AppEngineRule appEngineRule =
+  @RegisterExtension
+  final AppEngineRule appEngineRule =
       AppEngineRule.builder()
           .withDatastoreAndCloudSql()
           .withOfyTestEntities(TestObject.class)
           .build();
 
-  public VKeyTest() {}
-
   @Test
-  public void testOptionalAccessors() {
+  void testOptionalAccessors() {
     VKey<TestObject> key =
         VKey.create(TestObject.class, "foo", Key.create(TestObject.create("foo")));
     assertThat(key.maybeGetSqlKey().isPresent()).isTrue();

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

@@ -17,16 +17,13 @@ package google.registry.persistence.transaction;
 import static google.registry.persistence.transaction.TransactionManagerFactory.jpaTm;
 import static org.junit.Assert.assertThrows;
 
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
 
 /** JUnit test for {@link DummyJpaTransactionManager} */
-@RunWith(JUnit4.class)
-public class DummyJpaTransactionManagerTest {
+class DummyJpaTransactionManagerTest {
 
   @Test
-  public void throwsExceptionWhenAnyMethodIsInvoked() {
+  void throwsExceptionWhenAnyMethodIsInvoked() {
     assertThrows(UnsupportedOperationException.class, () -> jpaTm().transact(() -> null));
     assertThrows(UnsupportedOperationException.class, () -> jpaTm().getTransactionTime());
   }

core/src/test/java/google/registry/reporting/ReportingModuleTest.java

@@ -28,38 +28,35 @@ import javax.servlet.http.HttpServletRequest;
 import org.joda.time.DateTime;
 import org.joda.time.LocalDate;
 import org.joda.time.YearMonth;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 
 /** Unit tests for {@link ReportingModule}. */
-@RunWith(JUnit4.class)
-public class ReportingModuleTest {
+class ReportingModuleTest {
 
   private HttpServletRequest req = mock(HttpServletRequest.class);
   private Clock clock;
 
-  @Before
-  public void setUp() {
+  @BeforeEach
+  void beforeEach() {
     clock = new FakeClock(DateTime.parse("2017-07-01TZ"));
   }
 
   @Test
-  public void testEmptyYearMonthParameter_returnsEmptyYearMonthOptional() {
+  void testEmptyYearMonthParameter_returnsEmptyYearMonthOptional() {
     when(req.getParameter("yearMonth")).thenReturn("");
     Truth8.assertThat(ReportingModule.provideYearMonthOptional(req)).isEmpty();
   }
 
   @Test
-  public void testValidYearMonthParameter_returnsThatMonth() {
+  void testValidYearMonthParameter_returnsThatMonth() {
     when(req.getParameter("yearMonth")).thenReturn("2017-05");
     Truth8.assertThat(ReportingModule.provideYearMonthOptional(req))
         .hasValue(new YearMonth(2017, 5));
   }
 
   @Test
-  public void testInvalidYearMonthParameter_throwsException() {
+  void testInvalidYearMonthParameter_throwsException() {
     when(req.getParameter("yearMonth")).thenReturn("201705");
     BadRequestException thrown =
         assertThrows(
@@ -70,13 +67,13 @@ public class ReportingModuleTest {
   }
 
   @Test
-  public void testEmptyYearMonth_returnsLastMonth() {
+  void testEmptyYearMonth_returnsLastMonth() {
     assertThat(ReportingModule.provideYearMonth(Optional.empty(), new LocalDate(2017, 1, 6)))
         .isEqualTo(new YearMonth(2016, 12));
   }
 
   @Test
-  public void testGivenYearMonth_returnsThatMonth() {
+  void testGivenYearMonth_returnsThatMonth() {
     assertThat(
             ReportingModule.provideYearMonth(
                 Optional.of(new YearMonth(2017, 5)), new LocalDate(2017, 7, 6)))
@@ -84,20 +81,20 @@ public class ReportingModuleTest {
   }
 
   @Test
-  public void testEmptyDateParameter_returnsEmptyDateOptional() {
+  void testEmptyDateParameter_returnsEmptyDateOptional() {
     when(req.getParameter("date")).thenReturn("");
     Truth8.assertThat(ReportingModule.provideDateOptional(req)).isEmpty();
   }
 
   @Test
-  public void testValidDateParameter_returnsThatDate() {
+  void testValidDateParameter_returnsThatDate() {
     when(req.getParameter("date")).thenReturn("2017-05-13");
     Truth8.assertThat(ReportingModule.provideDateOptional(req))
         .hasValue(new LocalDate(2017, 5, 13));
   }
 
   @Test
-  public void testInvalidDateParameter_throwsException() {
+  void testInvalidDateParameter_throwsException() {
     when(req.getParameter("date")).thenReturn("20170513");
     BadRequestException thrown =
         assertThrows(BadRequestException.class, () -> ReportingModule.provideDateOptional(req));
@@ -107,13 +104,13 @@ public class ReportingModuleTest {
   }
 
   @Test
-  public void testEmptyDate_returnsToday() {
+  void testEmptyDate_returnsToday() {
     when(req.getParameter("date")).thenReturn(null);
     assertThat(ReportingModule.provideDate(req, clock)).isEqualTo(new LocalDate(2017, 7, 1));
   }
 
   @Test
-  public void testGivenDate_returnsThatDate() {
+  void testGivenDate_returnsThatDate() {
     when(req.getParameter("date")).thenReturn("2017-07-02");
     assertThat(ReportingModule.provideDate(req, clock)).isEqualTo(new LocalDate(2017, 7, 2));
   }

core/src/test/java/google/registry/reporting/billing/BillingEmailUtilsTest.java

@@ -35,23 +35,20 @@ import java.nio.charset.StandardCharsets;
 import javax.mail.MessagingException;
 import javax.mail.internet.InternetAddress;
 import org.joda.time.YearMonth;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 import org.mockito.ArgumentCaptor;
 
 /** Unit tests for {@link google.registry.reporting.billing.BillingEmailUtils}. */
-@RunWith(JUnit4.class)
-public class BillingEmailUtilsTest {
+class BillingEmailUtilsTest {
 
   private SendEmailService emailService;
   private BillingEmailUtils emailUtils;
   private GcsUtils gcsUtils;
   private ArgumentCaptor<EmailMessage> contentCaptor;
 
-  @Before
-  public void setUp() throws Exception {
+  @BeforeEach
+  void beforeEach() throws Exception {
     emailService = mock(SendEmailService.class);
     gcsUtils = mock(GcsUtils.class);
     when(gcsUtils.openInputStream(new GcsFilename("test-bucket", "results/REG-INV-2017-10.csv")))
@@ -74,7 +71,7 @@ public class BillingEmailUtilsTest {
   }
 
   @Test
-  public void testSuccess_emailOverallInvoice() throws MessagingException {
+  void testSuccess_emailOverallInvoice() throws MessagingException {
     emailUtils.emailOverallInvoice();
 
     verify(emailService).sendEmail(contentCaptor.capture());
@@ -98,7 +95,7 @@ public class BillingEmailUtilsTest {
   }
 
   @Test
-  public void testFailure_emailsAlert() throws MessagingException {
+  void testFailure_emailsAlert() throws MessagingException {
     doThrow(new RuntimeException(new MessagingException("expected")))
         .doNothing()
         .when(emailService)
@@ -116,7 +113,7 @@ public class BillingEmailUtilsTest {
   }
 
   @Test
-  public void testSuccess_sendAlertEmail() throws MessagingException {
+  void testSuccess_sendAlertEmail() throws MessagingException {
     emailUtils.sendAlertEmail("Alert!");
     verify(emailService).sendEmail(contentCaptor.capture());
     validateAlertMessage(contentCaptor.getValue(), "Alert!");

core/src/test/java/google/registry/reporting/billing/CopyDetailReportsActionTest.java

@@ -41,18 +41,15 @@ import google.registry.testing.FakeResponse;
 import google.registry.testing.FakeSleeper;
 import google.registry.util.Retrier;
 import java.io.IOException;
-import org.junit.Before;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
 
 /** Unit tests for {@link google.registry.reporting.billing.CopyDetailReportsAction}. */
-@RunWith(JUnit4.class)
-public class CopyDetailReportsActionTest {
+class CopyDetailReportsActionTest {
 
-  @Rule
-  public final AppEngineRule appEngine = AppEngineRule.builder().withDatastoreAndCloudSql().build();
+  @RegisterExtension
+  final AppEngineRule appEngine = AppEngineRule.builder().withDatastoreAndCloudSql().build();
 
   private final GcsService gcsService = GcsServiceFactory.createGcsService();
   private final GcsUtils gcsUtils = new GcsUtils(gcsService, 1024);
@@ -62,8 +59,8 @@ public class CopyDetailReportsActionTest {
   private BillingEmailUtils emailUtils;
   private CopyDetailReportsAction action;
 
-  @Before
-  public void setUp() {
+  @BeforeEach
+  void beforeEach() {
     persistResource(loadRegistrar("TheRegistrar").asBuilder().setDriveFolderId("0B-12345").build());
     persistResource(loadRegistrar("NewRegistrar").asBuilder().setDriveFolderId("0B-54321").build());
     response = new FakeResponse();
@@ -81,7 +78,7 @@ public class CopyDetailReportsActionTest {
   }
 
   @Test
-  public void testSuccess() throws IOException {
+  void testSuccess() throws IOException {
     writeGcsFile(
         gcsService,
         new GcsFilename("test-bucket", "results/invoice_details_2017-10_TheRegistrar_test.csv"),
@@ -112,7 +109,7 @@ public class CopyDetailReportsActionTest {
   }
 
   @Test
-  public void testSuccess_nonDetailReportFiles_notSent() throws IOException{
+  void testSuccess_nonDetailReportFiles_notSent() throws IOException {
     writeGcsFile(
         gcsService,
         new GcsFilename("test-bucket", "results/invoice_details_2017-10_TheRegistrar_hello.csv"),
@@ -137,7 +134,7 @@ public class CopyDetailReportsActionTest {
   }
 
   @Test
-  public void testSuccess_transientIOException_retries() throws IOException {
+  void testSuccess_transientIOException_retries() throws IOException {
     writeGcsFile(
         gcsService,
         new GcsFilename("test-bucket", "results/invoice_details_2017-10_TheRegistrar_hello.csv"),
@@ -159,7 +156,7 @@ public class CopyDetailReportsActionTest {
   }
 
   @Test
-  public void testFail_tooManyFailures_sendsAlertEmail_continues() throws IOException {
+  void testFail_tooManyFailures_sendsAlertEmail_continues() throws IOException {
     writeGcsFile(
         gcsService,
         new GcsFilename("test-bucket", "results/invoice_details_2017-10_TheRegistrar_hello.csv"),
@@ -202,7 +199,7 @@ public class CopyDetailReportsActionTest {
   }
 
   @Test
-  public void testFail_registrarDoesntExist_doesntCopy() throws IOException {
+  void testFail_registrarDoesntExist_doesntCopy() throws IOException {
     writeGcsFile(
         gcsService,
         new GcsFilename("test-bucket", "results/invoice_details_2017-10_notExistent_hello.csv"),
@@ -212,12 +209,11 @@ public class CopyDetailReportsActionTest {
   }
 
   @Test
-  public void testFail_noRegistrarFolderId_doesntCopy() throws IOException {
+  void testFail_noRegistrarFolderId_doesntCopy() throws IOException {
     persistResource(loadRegistrar("TheRegistrar").asBuilder().setDriveFolderId(null).build());
     writeGcsFile(
         gcsService,
-        new GcsFilename(
-            "test-bucket", "results/invoice_details_2017-10_TheRegistrar_hello.csv"),
+        new GcsFilename("test-bucket", "results/invoice_details_2017-10_TheRegistrar_hello.csv"),
         "hola,mundo\n3,4".getBytes(UTF_8));
     action.run();
     verifyNoInteractions(driveConnection);

core/src/test/java/google/registry/reporting/billing/GenerateInvoicesActionTest.java

@@ -36,18 +36,15 @@ import google.registry.testing.FakeResponse;
 import google.registry.testing.TaskQueueHelper.TaskMatcher;
 import java.io.IOException;
 import org.joda.time.YearMonth;
-import org.junit.Before;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
 
 /** Unit tests for {@link google.registry.reporting.billing.GenerateInvoicesAction}. */
-@RunWith(JUnit4.class)
-public class GenerateInvoicesActionTest {
+class GenerateInvoicesActionTest {
 
-  @Rule
-  public final AppEngineRule appEngine = AppEngineRule.builder().withTaskQueue().build();
+  @RegisterExtension
+  final AppEngineRule appEngine = AppEngineRule.builder().withTaskQueue().build();
 
   private Dataflow dataflow;
   private Projects projects;
@@ -55,10 +52,10 @@ public class GenerateInvoicesActionTest {
   private Launch launch;
   private FakeResponse response;
   private BillingEmailUtils emailUtils;
-  GenerateInvoicesAction action;
+  private GenerateInvoicesAction action;
 
-  @Before
-  public void setUp() throws IOException {
+  @BeforeEach
+  void beforeEach() throws IOException {
     dataflow = mock(Dataflow.class);
     projects = mock(Projects.class);
     templates = mock(Templates.class);
@@ -77,7 +74,7 @@ public class GenerateInvoicesActionTest {
   }
 
   @Test
-  public void testLaunchTemplateJob_withPublish() throws Exception {
+  void testLaunchTemplateJob_withPublish() throws Exception {
     action =
         new GenerateInvoicesAction(
             "test-project",
@@ -113,7 +110,7 @@ public class GenerateInvoicesActionTest {
   }
 
   @Test
-  public void testLaunchTemplateJob_withoutPublish() throws Exception {
+  void testLaunchTemplateJob_withoutPublish() throws Exception {
     action =
         new GenerateInvoicesAction(
             "test-project",
@@ -142,7 +139,7 @@ public class GenerateInvoicesActionTest {
   }
 
   @Test
-  public void testCaughtIOException() throws IOException {
+  void testCaughtIOException() throws IOException {
     when(launch.execute()).thenThrow(new IOException("expected"));
     action =
         new GenerateInvoicesAction(

core/src/test/java/google/registry/reporting/billing/PublishInvoicesActionTest.java

@@ -35,15 +35,12 @@ import google.registry.testing.FakeResponse;
 import google.registry.testing.TaskQueueHelper.TaskMatcher;
 import java.io.IOException;
 import org.joda.time.YearMonth;
-import org.junit.Before;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
 
 /** Unit tests for {@link PublishInvoicesAction}. */
-@RunWith(JUnit4.class)
-public class PublishInvoicesActionTest {
+class PublishInvoicesActionTest {
 
   private Get get;
   private BillingEmailUtils emailUtils;
@@ -52,11 +49,11 @@ public class PublishInvoicesActionTest {
   private FakeResponse response;
   private PublishInvoicesAction uploadAction;
 
-  @Rule
-  public final AppEngineRule appEngine = AppEngineRule.builder().withTaskQueue().build();
+  @RegisterExtension
+  final AppEngineRule appEngine = AppEngineRule.builder().withTaskQueue().build();
 
-  @Before
-  public void setUp() throws IOException {
+  @BeforeEach
+  void beforeEach() throws IOException {
     Dataflow dataflow = mock(Dataflow.class);
     Projects projects = mock(Projects.class);
     Jobs jobs = mock(Jobs.class);
@@ -74,7 +71,7 @@ public class PublishInvoicesActionTest {
   }
 
   @Test
-  public void testJobDone_enqueuesCopyAction_emailsResults() {
+  void testJobDone_enqueuesCopyAction_emailsResults() {
     expectedJob.setCurrentState("JOB_STATE_DONE");
     uploadAction.run();
     assertThat(response.getStatus()).isEqualTo(SC_OK);
@@ -88,7 +85,7 @@ public class PublishInvoicesActionTest {
   }
 
   @Test
-  public void testJobFailed_returnsNonRetriableResponse() {
+  void testJobFailed_returnsNonRetriableResponse() {
     expectedJob.setCurrentState("JOB_STATE_FAILED");
     uploadAction.run();
     assertThat(response.getStatus()).isEqualTo(SC_NO_CONTENT);
@@ -96,14 +93,14 @@ public class PublishInvoicesActionTest {
   }
 
   @Test
-  public void testJobIndeterminate_returnsRetriableResponse() {
+  void testJobIndeterminate_returnsRetriableResponse() {
     expectedJob.setCurrentState("JOB_STATE_RUNNING");
     uploadAction.run();
     assertThat(response.getStatus()).isEqualTo(SC_NOT_MODIFIED);
   }
 
   @Test
-  public void testIOException_returnsFailureMessage() throws IOException {
+  void testIOException_returnsFailureMessage() throws IOException {
     when(get.execute()).thenThrow(new IOException("expected"));
     uploadAction.run();
     assertThat(response.getStatus()).isEqualTo(SC_INTERNAL_SERVER_ERROR);

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

@@ -19,13 +19,10 @@ import static com.google.common.truth.Truth.assertThat;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import org.joda.time.YearMonth;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
 
 /** Unit tests for {@link ActivityReportingQueryBuilder}. */
-@RunWith(JUnit4.class)
-public class ActivityReportingQueryBuilderTest {
+class ActivityReportingQueryBuilderTest {
 
   private final YearMonth yearMonth = new YearMonth(2017, 9);
 
@@ -39,7 +36,7 @@ public class ActivityReportingQueryBuilderTest {
   }
 
   @Test
-  public void testAggregateQueryMatch() {
+  void testAggregateQueryMatch() {
     ActivityReportingQueryBuilder queryBuilder = getQueryBuilder();
     assertThat(queryBuilder.getReportQuery(yearMonth))
         .isEqualTo(
@@ -48,7 +45,7 @@ public class ActivityReportingQueryBuilderTest {
   }
 
   @Test
-  public void testIntermediaryQueryMatch() {
+  void testIntermediaryQueryMatch() {
     ImmutableList<String> expectedQueryNames =
         ImmutableList.of(
             ActivityReportingQueryBuilder.REGISTRAR_OPERATING_STATUS,

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

@@ -33,17 +33,12 @@ import google.registry.testing.AppEngineRule;
 import java.io.IOException;
 import java.util.List;
 import java.util.Map;
-import org.junit.Before;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
 
-/**
- * Unit tests for {@link IcannHttpReporter}.
- */
-@RunWith(JUnit4.class)
-public class IcannHttpReporterTest {
+/** Unit tests for {@link IcannHttpReporter}. */
+class IcannHttpReporterTest {
 
   private static final ByteSource IIRDEA_GOOD_XML = ReportingTestData.loadBytes("iirdea_good.xml");
   private static final ByteSource IIRDEA_BAD_XML = ReportingTestData.loadBytes("iirdea_bad.xml");
@@ -51,32 +46,32 @@ public class IcannHttpReporterTest {
 
   private MockLowLevelHttpRequest mockRequest;
 
-  @Rule
-  public AppEngineRule appEngineRule =
-      new AppEngineRule.Builder().withDatastoreAndCloudSql().build();
+  @RegisterExtension
+  AppEngineRule appEngineRule = new AppEngineRule.Builder().withDatastoreAndCloudSql().build();
 
-  private MockHttpTransport createMockTransport (final ByteSource iirdeaResponse) {
+  private MockHttpTransport createMockTransport(final ByteSource iirdeaResponse) {
     return new MockHttpTransport() {
       @Override
       public LowLevelHttpRequest buildRequest(String method, String url) {
-        mockRequest = new MockLowLevelHttpRequest() {
-          @Override
-          public LowLevelHttpResponse execute() throws IOException {
-            MockLowLevelHttpResponse response = new MockLowLevelHttpResponse();
-            response.setStatusCode(200);
-            response.setContentType(PLAIN_TEXT_UTF_8.toString());
-            response.setContent(iirdeaResponse.read());
-            return response;
-          }
-        };
+        mockRequest =
+            new MockLowLevelHttpRequest() {
+              @Override
+              public LowLevelHttpResponse execute() throws IOException {
+                MockLowLevelHttpResponse response = new MockLowLevelHttpResponse();
+                response.setStatusCode(200);
+                response.setContentType(PLAIN_TEXT_UTF_8.toString());
+                response.setContent(iirdeaResponse.read());
+                return response;
+              }
+            };
         mockRequest.setUrl(url);
         return mockRequest;
       }
     };
   }
 
-  @Before
-  public void setUp() {
+  @BeforeEach
+  void beforeEach() {
     createTld("test");
     createTld("xn--abc123");
   }
@@ -91,7 +86,7 @@ public class IcannHttpReporterTest {
   }
 
   @Test
-  public void testSuccess() throws Exception {
+  void testSuccess() throws Exception {
     IcannHttpReporter reporter = createReporter();
     reporter.send(FAKE_PAYLOAD, "test-transactions-201706.csv");
 
@@ -105,7 +100,7 @@ public class IcannHttpReporterTest {
   }
 
   @Test
-  public void testSuccess_internationalTld() throws Exception {
+  void testSuccess_internationalTld() throws Exception {
     IcannHttpReporter reporter = createReporter();
     reporter.send(FAKE_PAYLOAD, "xn--abc123-transactions-201706.csv");
 
@@ -119,14 +114,14 @@ public class IcannHttpReporterTest {
   }
 
   @Test
-  public void testFail_BadIirdeaResponse() throws Exception {
+  void testFail_BadIirdeaResponse() throws Exception {
     IcannHttpReporter reporter = createReporter();
     reporter.httpTransport = createMockTransport(IIRDEA_BAD_XML);
     assertThat(reporter.send(FAKE_PAYLOAD, "test-transactions-201706.csv")).isFalse();
   }
 
   @Test
-  public void testFail_invalidFilename_nonSixDigitYearMonth() {
+  void testFail_invalidFilename_nonSixDigitYearMonth() {
     IcannHttpReporter reporter = createReporter();
     IllegalArgumentException thrown =
         assertThrows(
@@ -140,7 +135,7 @@ public class IcannHttpReporterTest {
   }
 
   @Test
-  public void testFail_invalidFilename_notActivityOrTransactions() {
+  void testFail_invalidFilename_notActivityOrTransactions() {
     IcannHttpReporter reporter = createReporter();
     IllegalArgumentException thrown =
         assertThrows(
@@ -153,7 +148,7 @@ public class IcannHttpReporterTest {
   }
 
   @Test
-  public void testFail_invalidFilename_invalidTldName() {
+  void testFail_invalidFilename_invalidTldName() {
     IcannHttpReporter reporter = createReporter();
     IllegalArgumentException thrown =
         assertThrows(
@@ -167,7 +162,7 @@ public class IcannHttpReporterTest {
   }
 
   @Test
-  public void testFail_invalidFilename_tldDoesntExist() {
+  void testFail_invalidFilename_tldDoesntExist() {
     IcannHttpReporter reporter = createReporter();
     IllegalArgumentException thrown =
         assertThrows(

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

@@ -19,16 +19,13 @@ import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.when;
 
 import javax.servlet.http.HttpServletRequest;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
 
 /** Unit tests for {@link google.registry.reporting.icann.IcannReportingModule}. */
-@RunWith(JUnit4.class)
-public class IcannReportingModuleTest {
+class IcannReportingModuleTest {
 
   @Test
-  public void testProvideReportTypes() {
+  void testProvideReportTypes() {
     HttpServletRequest req = mock(HttpServletRequest.class);
 
     when(req.getParameter("reportTypes")).thenReturn(null);

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

@@ -38,23 +38,20 @@ import google.registry.testing.FakeResponse;
 import java.util.concurrent.Executor;
 import java.util.concurrent.TimeUnit;
 import org.joda.time.YearMonth;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
 
 /** Unit tests for {@link google.registry.reporting.icann.IcannReportingStager}. */
-@RunWith(JUnit4.class)
-public class IcannReportingStagerTest {
+class IcannReportingStagerTest {
 
-  BigqueryConnection bigquery = mock(BigqueryConnection.class);
+  private BigqueryConnection bigquery = mock(BigqueryConnection.class);
   FakeResponse response = new FakeResponse();
-  GcsService gcsService = GcsServiceFactory.createGcsService();
-  YearMonth yearMonth = new YearMonth(2017, 6);
-  String subdir = "icann/monthly/2017-06";
+  private GcsService gcsService = GcsServiceFactory.createGcsService();
+  private YearMonth yearMonth = new YearMonth(2017, 6);
+  private String subdir = "icann/monthly/2017-06";
 
-  @Rule
-  public final AppEngineRule appEngine =
+  @RegisterExtension
+  final AppEngineRule appEngine =
       AppEngineRule.builder().withDatastoreAndCloudSql().withLocalModules().build();
 
   private IcannReportingStager createStager() {
@@ -74,16 +71,17 @@ public class IcannReportingStagerTest {
 
   private void setUpBigquery() {
     when(bigquery.query(any(String.class), any(DestinationTable.class))).thenReturn(fakeFuture());
-    DestinationTable.Builder tableBuilder = new DestinationTable.Builder()
-        .datasetId("testdataset")
-        .type(TableType.TABLE)
-        .name("tablename")
-        .overwrite(true);
+    DestinationTable.Builder tableBuilder =
+        new DestinationTable.Builder()
+            .datasetId("testdataset")
+            .type(TableType.TABLE)
+            .name("tablename")
+            .overwrite(true);
     when(bigquery.buildDestinationTable(any(String.class))).thenReturn(tableBuilder);
   }
 
   @Test
-  public void testRunSuccess_activityReport() throws Exception {
+  void testRunSuccess_activityReport() throws Exception {
     setUpBigquery();
     ImmutableTable<Integer, TableFieldSchema, Object> activityReportTable =
         new ImmutableTable.Builder<Integer, TableFieldSchema, Object>()
@@ -113,7 +111,7 @@ public class IcannReportingStagerTest {
   }
 
   @Test
-  public void testRunSuccess_transactionsReport() throws Exception {
+  void testRunSuccess_transactionsReport() throws Exception {
     setUpBigquery();
     /*
       The fake table result looks like:
@@ -157,7 +155,7 @@ public class IcannReportingStagerTest {
   }
 
   @Test
-  public void testRunSuccess_createAndUploadManifest() throws Exception {
+  void testRunSuccess_createAndUploadManifest() throws Exception {
     IcannReportingStager stager = createStager();
     ImmutableList<String> filenames =
         ImmutableList.of("fooTld-transactions-201706.csv", "barTld-activity-201706.csv");
@@ -204,4 +202,3 @@ public class IcannReportingStagerTest {
     };
   }
 }
-

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

@@ -39,28 +39,25 @@ import google.registry.util.SendEmailService;
 import java.util.Optional;
 import javax.mail.internet.InternetAddress;
 import org.joda.time.YearMonth;
-import org.junit.Before;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
 
 /** Unit tests for {@link google.registry.reporting.icann.IcannReportingStagingAction}. */
-@RunWith(JUnit4.class)
-public class IcannReportingStagingActionTest {
+class IcannReportingStagingActionTest {
 
-  FakeResponse response = new FakeResponse();
-  IcannReportingStager stager = mock(IcannReportingStager.class);
-  YearMonth yearMonth = new YearMonth(2017, 6);
-  String subdir = "default/dir";
-  IcannReportingStagingAction action;
+  private FakeResponse response = new FakeResponse();
+  private IcannReportingStager stager = mock(IcannReportingStager.class);
+  private YearMonth yearMonth = new YearMonth(2017, 6);
+  private String subdir = "default/dir";
+  private IcannReportingStagingAction action;
 
-  @Rule
-  public final AppEngineRule appEngine =
+  @RegisterExtension
+  final AppEngineRule appEngine =
       AppEngineRule.builder().withDatastoreAndCloudSql().withLocalModules().withTaskQueue().build();
 
-  @Before
-  public void setUp() throws Exception {
+  @BeforeEach
+  void beforeEach() throws Exception {
     action = new IcannReportingStagingAction();
     action.yearMonth = yearMonth;
     action.overrideSubdir = Optional.of(subdir);
@@ -84,7 +81,7 @@ public class IcannReportingStagingActionTest {
   }
 
   @Test
-  public void testActivityReportingMode_onlyStagesActivityReports() throws Exception {
+  void testActivityReportingMode_onlyStagesActivityReports() throws Exception {
     action.reportTypes = ImmutableSet.of(ReportType.ACTIVITY);
     action.run();
     verify(stager).stageReports(yearMonth, subdir, ReportType.ACTIVITY);
@@ -100,7 +97,7 @@ public class IcannReportingStagingActionTest {
   }
 
   @Test
-  public void testAbsentReportingMode_stagesBothReports() throws Exception {
+  void testAbsentReportingMode_stagesBothReports() throws Exception {
     action.run();
     verify(stager).stageReports(yearMonth, subdir, ReportType.ACTIVITY);
     verify(stager).stageReports(yearMonth, subdir, ReportType.TRANSACTIONS);
@@ -116,7 +113,7 @@ public class IcannReportingStagingActionTest {
   }
 
   @Test
-  public void testRetryOnBigqueryException() throws Exception {
+  void testRetryOnBigqueryException() throws Exception {
     when(stager.stageReports(yearMonth, subdir, ReportType.TRANSACTIONS))
         .thenThrow(new BigqueryJobFailureException("Expected failure", null, null, null))
         .thenReturn(ImmutableList.of("c", "d"));
@@ -135,7 +132,7 @@ public class IcannReportingStagingActionTest {
   }
 
   @Test
-  public void testEmailEng_onMoreThanRetriableFailure() throws Exception {
+  void testEmailEng_onMoreThanRetriableFailure() throws Exception {
     action.reportTypes = ImmutableSet.of(ReportType.ACTIVITY);
     when(stager.stageReports(yearMonth, subdir, ReportType.ACTIVITY))
         .thenThrow(new BigqueryJobFailureException("Expected failure", null, null, null));
@@ -160,25 +157,22 @@ public class IcannReportingStagingActionTest {
   }
 
   @Test
-  public void testEmptySubDir_returnsDefaultSubdir() {
+  void testEmptySubDir_returnsDefaultSubdir() {
     action.overrideSubdir = Optional.empty();
     assertThat(action.getSubdir(new YearMonth(2017, 6))).isEqualTo("icann/monthly/2017-06");
   }
 
   @Test
-  public void testGivenSubdir_returnsManualSubdir() {
+  void testGivenSubdir_returnsManualSubdir() {
     action.overrideSubdir = Optional.of("manual/dir");
     assertThat(action.getSubdir(new YearMonth(2017, 6))).isEqualTo("manual/dir");
   }
 
   @Test
-  public void testInvalidSubdir_throwsException() {
+  void testInvalidSubdir_throwsException() {
     action.overrideSubdir = Optional.of("/whoops");
     BadRequestException thrown =
-        assertThrows(
-            BadRequestException.class,
-            () ->
-                action.getSubdir(new YearMonth(2017, 6)));
+        assertThrows(BadRequestException.class, () -> action.getSubdir(new YearMonth(2017, 6)));
     assertThat(thrown)
         .hasMessageThat()
         .contains("subdir must not start or end with a \"/\", got /whoops instead.");

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

@@ -50,18 +50,15 @@ import java.util.logging.Level;
 import java.util.logging.Logger;
 import javax.mail.internet.InternetAddress;
 import org.joda.time.DateTime;
-import org.junit.Before;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
 
 /** Unit tests for {@link google.registry.reporting.icann.IcannReportingUploadAction} */
-@RunWith(JUnit4.class)
-public class IcannReportingUploadActionTest {
+class IcannReportingUploadActionTest {
 
-  @Rule
-  public final AppEngineRule appEngine = AppEngineRule.builder().withDatastoreAndCloudSql().build();
+  @RegisterExtension
+  final AppEngineRule appEngine = AppEngineRule.builder().withDatastoreAndCloudSql().build();
 
   private static final byte[] PAYLOAD_SUCCESS = "test,csv\n13,37".getBytes(UTF_8);
   private static final byte[] PAYLOAD_FAIL = "ahah,csv\n12,34".getBytes(UTF_8);
@@ -89,8 +86,8 @@ public class IcannReportingUploadActionTest {
     return action;
   }
 
-  @Before
-  public void before() throws Exception {
+  @BeforeEach
+  void beforeEach() throws Exception {
     createTlds("tld", "foo");
     writeGcsFile(
         gcsService,
@@ -129,7 +126,7 @@ public class IcannReportingUploadActionTest {
   }
 
   @Test
-  public void testSuccess() throws Exception {
+  void testSuccess() throws Exception {
     IcannReportingUploadAction action = createAction();
     action.run();
     verify(mockReporter).send(PAYLOAD_SUCCESS, "foo-activity-200606.csv");
@@ -152,7 +149,7 @@ public class IcannReportingUploadActionTest {
   }
 
   @Test
-  public void testSuccess_january() throws Exception {
+  void testSuccess_january() throws Exception {
     clock.setTo(DateTime.parse("2006-01-22T00:30:00Z"));
     persistResource(
         Cursor.create(
@@ -189,7 +186,7 @@ public class IcannReportingUploadActionTest {
   }
 
   @Test
-  public void testSuccess_advancesCursor() throws Exception {
+  void testSuccess_advancesCursor() throws Exception {
     writeGcsFile(
         gcsService,
         new GcsFilename("basin/icann/monthly/2006-06", "tld-activity-200606.csv"),
@@ -207,7 +204,7 @@ public class IcannReportingUploadActionTest {
   }
 
   @Test
-  public void testSuccess_noUploadsNeeded() throws Exception {
+  void testSuccess_noUploadsNeeded() throws Exception {
     clock.setTo(DateTime.parse("2006-5-01T00:30:00Z"));
     IcannReportingUploadAction action = createAction();
     action.run();
@@ -223,7 +220,7 @@ public class IcannReportingUploadActionTest {
   }
 
   @Test
-  public void testSuccess_withRetry() throws Exception {
+  void testSuccess_withRetry() throws Exception {
     IcannReportingUploadAction action = createAction();
     when(mockReporter.send(PAYLOAD_SUCCESS, "tld-transactions-200606.csv"))
         .thenThrow(new IOException("Expected exception."))
@@ -248,7 +245,7 @@ public class IcannReportingUploadActionTest {
   }
 
   @Test
-  public void testFailure_quicklySkipsOverNonRetryableUploadException() throws Exception {
+  void testFailure_quicklySkipsOverNonRetryableUploadException() throws Exception {
     runTest_nonRetryableException(
         new IOException(
             "<msg>A report for that month already exists, the cut-off date already"
@@ -256,13 +253,13 @@ public class IcannReportingUploadActionTest {
   }
 
   @Test
-  public void testFailure_quicklySkipsOverIpAllowListException() throws Exception {
+  void testFailure_quicklySkipsOverIpAllowListException() throws Exception {
     runTest_nonRetryableException(
         new IOException("Your IP address 25.147.130.158 is not allowed to connect"));
   }
 
   @Test
-  public void testFailure_cursorIsNotAdvancedForward() throws Exception {
+  void testFailure_cursorIsNotAdvancedForward() throws Exception {
     runTest_nonRetryableException(
         new IOException("Your IP address 25.147.130.158 is not allowed to connect"));
     ofy().clearSessionCache();
@@ -275,7 +272,7 @@ public class IcannReportingUploadActionTest {
   }
 
   @Test
-  public void testNotRunIfCursorDateIsAfterToday() throws Exception {
+  void testNotRunIfCursorDateIsAfterToday() throws Exception {
     clock.setTo(DateTime.parse("2006-05-01T00:30:00Z"));
     IcannReportingUploadAction action = createAction();
     action.run();
@@ -316,7 +313,7 @@ public class IcannReportingUploadActionTest {
   }
 
   @Test
-  public void testFail_fileNotFound() throws Exception {
+  void testFail_fileNotFound() throws Exception {
     clock.setTo(DateTime.parse("2006-01-22T00:30:00Z"));
     persistResource(
         Cursor.create(
@@ -332,7 +329,7 @@ public class IcannReportingUploadActionTest {
   }
 
   @Test
-  public void testWarning_fileNotStagedYet() throws Exception {
+  void testWarning_fileNotStagedYet() throws Exception {
     persistResource(
         Cursor.create(
             CursorType.ICANN_UPLOAD_ACTIVITY, DateTime.parse("2006-08-01TZ"), Registry.get("foo")));
@@ -349,7 +346,7 @@ public class IcannReportingUploadActionTest {
   }
 
   @Test
-  public void testFailure_lockIsntAvailable() throws Exception {
+  void testFailure_lockIsntAvailable() throws Exception {
     IcannReportingUploadAction action = createAction();
     action.lockHandler = new FakeLockHandler(false);
     ServiceUnavailableException thrown =
@@ -360,7 +357,7 @@ public class IcannReportingUploadActionTest {
   }
 
   @Test
-  public void testSuccess_nullCursorsInitiatedToFirstOfNextMonth() throws Exception {
+  void testSuccess_nullCursorsInitiatedToFirstOfNextMonth() throws Exception {
     createTlds("new");
 
     IcannReportingUploadAction action = createAction();

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

@@ -19,13 +19,10 @@ import static com.google.common.truth.Truth.assertThat;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import org.joda.time.YearMonth;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
 
 /** Unit tests for {@link ActivityReportingQueryBuilder}. */
-@RunWith(JUnit4.class)
-public class TransactionsReportingQueryBuilderTest {
+class TransactionsReportingQueryBuilderTest {
 
   private final YearMonth yearMonth = new YearMonth(2017, 9);
 
@@ -36,7 +33,7 @@ public class TransactionsReportingQueryBuilderTest {
   }
 
   @Test
-  public void testAggregateQueryMatch() {
+  void testAggregateQueryMatch() {
     TransactionsReportingQueryBuilder queryBuilder = getQueryBuilder();
     assertThat(queryBuilder.getReportQuery(yearMonth))
         .isEqualTo(
@@ -45,7 +42,7 @@ public class TransactionsReportingQueryBuilderTest {
   }
 
   @Test
-  public void testIntermediaryQueryMatch() {
+  void testIntermediaryQueryMatch() {
     ImmutableList<String> expectedQueryNames =
         ImmutableList.of(
             TransactionsReportingQueryBuilder.TRANSACTIONS_REPORT_AGGREGATION,

core/src/test/java/google/registry/reporting/spec11/GenerateSpec11ReportActionTest.java

@@ -36,18 +36,15 @@ import google.registry.testing.FakeResponse;
 import google.registry.testing.TaskQueueHelper.TaskMatcher;
 import java.io.IOException;
 import org.joda.time.LocalDate;
-import org.junit.Before;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
 
 /** Unit tests for {@link google.registry.reporting.spec11.GenerateSpec11ReportAction}. */
-@RunWith(JUnit4.class)
-public class GenerateSpec11ReportActionTest {
+class GenerateSpec11ReportActionTest {
 
-  @Rule
-  public final AppEngineRule appEngine = AppEngineRule.builder().withTaskQueue().build();
+  @RegisterExtension
+  final AppEngineRule appEngine = AppEngineRule.builder().withTaskQueue().build();
 
   private FakeResponse response;
   private Dataflow dataflow;
@@ -57,8 +54,8 @@ public class GenerateSpec11ReportActionTest {
 
   private GenerateSpec11ReportAction action;
 
-  @Before
-  public void setUp() throws IOException {
+  @BeforeEach
+  void beforeEach() throws IOException {
     response = new FakeResponse();
     dataflow = mock(Dataflow.class);
 
@@ -79,7 +76,7 @@ public class GenerateSpec11ReportActionTest {
   }
 
   @Test
-  public void testLaunch_success() throws IOException {
+  void testLaunch_success() throws IOException {
     action =
         new GenerateSpec11ReportAction(
             "test",

core/src/test/java/google/registry/reporting/spec11/PublishSpec11ReportActionTest.java

@@ -41,14 +41,11 @@ import google.registry.testing.FakeResponse;
 import java.io.IOException;
 import java.util.Optional;
 import org.joda.time.LocalDate;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 
 /** Unit tests for {@link PublishSpec11ReportAction}. */
-@RunWith(JUnit4.class)
-public class PublishSpec11ReportActionTest {
+class PublishSpec11ReportActionTest {
 
   private final LocalDate date = new LocalDate(2018, 6, 5);
 
@@ -63,8 +60,8 @@ public class PublishSpec11ReportActionTest {
   private FakeResponse response;
   private PublishSpec11ReportAction publishAction;
 
-  @Before
-  public void setUp() throws Exception {
+  @BeforeEach
+  void beforeEach() throws Exception {
     dataflow = mock(Dataflow.class);
     projects = mock(Projects.class);
     jobs = mock(Jobs.class);
@@ -91,7 +88,7 @@ public class PublishSpec11ReportActionTest {
   }
 
   @Test
-  public void testJobDone_emailsOnlyMonthlyResultsOnSecondOfMonth() throws Exception {
+  void testJobDone_emailsOnlyMonthlyResultsOnSecondOfMonth() throws Exception {
     LocalDate secondOfMonth = date.withDayOfMonth(2);
     when(parser.getRegistrarThreatMatches(secondOfMonth)).thenReturn(sampleThreatMatches());
     expectedJob.setCurrentState("JOB_STATE_DONE");
@@ -117,7 +114,7 @@ public class PublishSpec11ReportActionTest {
   }
 
   @Test
-  public void testJobFailed_returnsNonRetriableResponse() {
+  void testJobFailed_returnsNonRetriableResponse() {
     expectedJob.setCurrentState("JOB_STATE_FAILED");
     publishAction.run();
     assertThat(response.getStatus()).isEqualTo(SC_NO_CONTENT);
@@ -128,7 +125,7 @@ public class PublishSpec11ReportActionTest {
   }
 
   @Test
-  public void testJobIndeterminate_returnsRetriableResponse() {
+  void testJobIndeterminate_returnsRetriableResponse() {
     expectedJob.setCurrentState("JOB_STATE_RUNNING");
     publishAction.run();
     assertThat(response.getStatus()).isEqualTo(SC_NOT_MODIFIED);
@@ -136,7 +133,7 @@ public class PublishSpec11ReportActionTest {
   }
 
   @Test
-  public void testIOException_returnsFailureMessage() throws IOException {
+  void testIOException_returnsFailureMessage() throws IOException {
     when(get.execute()).thenThrow(new IOException("expected"));
     publishAction.run();
     assertThat(response.getStatus()).isEqualTo(SC_INTERNAL_SERVER_ERROR);
@@ -149,7 +146,7 @@ public class PublishSpec11ReportActionTest {
   }
 
   @Test
-  public void testJobDone_onlyDailyResults() throws Exception {
+  void testJobDone_onlyDailyResults() throws Exception {
     LocalDate yesterday = date.minusDays(1);
     when(parser.getPreviousDateWithMatches(date)).thenReturn(Optional.of(yesterday));
     when(parser.getRegistrarThreatMatches(date)).thenReturn(sampleThreatMatches());
@@ -167,7 +164,7 @@ public class PublishSpec11ReportActionTest {
   }
 
   @Test
-  public void testJobDone_multipleEntriesWithSameEmail() throws Exception {
+  void testJobDone_multipleEntriesWithSameEmail() throws Exception {
     LocalDate yesterday = date.minusDays(1);
     when(parser.getPreviousDateWithMatches(date)).thenReturn(Optional.of(yesterday));
     when(parser.getRegistrarThreatMatches(yesterday)).thenReturn(ImmutableSet.of());
@@ -200,7 +197,7 @@ public class PublishSpec11ReportActionTest {
   }
 
   @Test
-  public void testJobDone_noDifferentResults() throws Exception {
+  void testJobDone_noDifferentResults() throws Exception {
     LocalDate yesterday = date.minusDays(1);
     when(parser.getPreviousDateWithMatches(date)).thenReturn(Optional.of(yesterday));
     when(parser.getRegistrarThreatMatches(date)).thenReturn(sampleThreatMatches());
@@ -218,7 +215,7 @@ public class PublishSpec11ReportActionTest {
   }
 
   @Test
-  public void testJobDone_failsDueToNoPreviousResults() {
+  void testJobDone_failsDueToNoPreviousResults() {
     when(parser.getPreviousDateWithMatches(date)).thenReturn(Optional.empty());
     expectedJob.setCurrentState("JOB_STATE_DONE");
     publishAction.run();

core/src/test/java/google/registry/reporting/spec11/Spec11EmailUtilsTest.java

@@ -47,16 +47,13 @@ import java.util.Optional;
 import javax.mail.MessagingException;
 import javax.mail.internet.InternetAddress;
 import org.joda.time.LocalDate;
-import org.junit.Before;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
 import org.mockito.ArgumentCaptor;
 
 /** Unit tests for {@link Spec11EmailUtils}. */
-@RunWith(JUnit4.class)
-public class Spec11EmailUtilsTest {
+class Spec11EmailUtilsTest {
 
   private static final ImmutableList<String> FAKE_RESOURCES = ImmutableList.of("foo");
   private static final String DAILY_EMAIL_FORMAT =
@@ -95,8 +92,8 @@ public class Spec11EmailUtilsTest {
           + " domains are added to these lists.</p><p>If you have any questions regarding this"
           + " notice, please contact abuse@test.com.</p>";
 
-  @Rule
-  public final AppEngineRule appEngine = AppEngineRule.builder().withDatastoreAndCloudSql().build();
+  @RegisterExtension
+  final AppEngineRule appEngine = AppEngineRule.builder().withDatastoreAndCloudSql().build();
 
   private SendEmailService emailService;
   private Spec11EmailUtils emailUtils;
@@ -107,8 +104,8 @@ public class Spec11EmailUtilsTest {
   private DomainBase aDomain;
   private DomainBase bDomain;
 
-  @Before
-  public void setUp() throws Exception {
+  @BeforeEach
+  void beforeEach() throws Exception {
     emailService = mock(SendEmailService.class);
     parser = mock(Spec11RegistrarThreatMatchesParser.class);
     when(parser.getRegistrarThreatMatches(date)).thenReturn(sampleThreatMatches());
@@ -131,7 +128,7 @@ public class Spec11EmailUtilsTest {
   }
 
   @Test
-  public void testSuccess_emailMonthlySpec11Reports() throws Exception {
+  void testSuccess_emailMonthlySpec11Reports() throws Exception {
     emailUtils.emailSpec11Reports(
         date,
         Spec11EmailSoyInfo.MONTHLY_SPEC_11_EMAIL,
@@ -169,7 +166,7 @@ public class Spec11EmailUtilsTest {
   }
 
   @Test
-  public void testSuccess_emailDailySpec11Reports() throws Exception {
+  void testSuccess_emailDailySpec11Reports() throws Exception {
     emailUtils.emailSpec11Reports(
         date,
         Spec11EmailSoyInfo.DAILY_SPEC_11_EMAIL,
@@ -207,14 +204,12 @@ public class Spec11EmailUtilsTest {
   }
 
   @Test
-  public void testSuccess_skipsInactiveDomain() throws Exception {
+  void testSuccess_skipsInactiveDomain() throws Exception {
     // CLIENT_HOLD and SERVER_HOLD mean no DNS so we don't need to email it out
     persistResource(
-        ofy().load().entity(aDomain).now().asBuilder().addStatusValue(SERVER_HOLD)
-            .build());
+        ofy().load().entity(aDomain).now().asBuilder().addStatusValue(SERVER_HOLD).build());
     persistResource(
-        ofy().load().entity(bDomain).now().asBuilder().addStatusValue(CLIENT_HOLD)
-            .build());
+        ofy().load().entity(bDomain).now().asBuilder().addStatusValue(CLIENT_HOLD).build());
     emailUtils.emailSpec11Reports(
         date,
         Spec11EmailSoyInfo.MONTHLY_SPEC_11_EMAIL,
@@ -242,7 +237,7 @@ public class Spec11EmailUtilsTest {
   }
 
   @Test
-  public void testOneFailure_sendsAlert() throws Exception {
+  void testOneFailure_sendsAlert() throws Exception {
     // If there is one failure, we should still send the other message and then an alert email
     LinkedHashSet<RegistrarThreatMatches> matches = new LinkedHashSet<>();
     matches.add(getMatchA());
@@ -297,7 +292,7 @@ public class Spec11EmailUtilsTest {
   }
 
   @Test
-  public void testSuccess_sendAlertEmail() throws Exception {
+  void testSuccess_sendAlertEmail() throws Exception {
     emailUtils.sendAlertEmail("Spec11 Pipeline Alert: 2018-07", "Alert!");
     verify(emailService).sendEmail(contentCaptor.capture());
     validateMessage(
@@ -311,7 +306,7 @@ public class Spec11EmailUtilsTest {
   }
 
   @Test
-  public void testSuccess_useWhoisAbuseEmailIfAvailable() throws Exception {
+  void testSuccess_useWhoisAbuseEmailIfAvailable() throws Exception {
     // if John Doe is the whois abuse contact, email them instead of the regular email
     persistResource(
         AppEngineRule.makeRegistrarContact2()
@@ -330,7 +325,7 @@ public class Spec11EmailUtilsTest {
   }
 
   @Test
-  public void testFailure_badClientId() {
+  void testFailure_badClientId() {
     RuntimeException thrown =
         assertThrows(
             RuntimeException.class,

core/src/test/java/google/registry/reporting/spec11/Spec11RegistrarThreatMatchesParserTest.java

@@ -30,14 +30,11 @@ import java.io.ByteArrayInputStream;
 import java.nio.charset.StandardCharsets;
 import org.joda.time.LocalDate;
 import org.json.JSONObject;
-import org.junit.Before;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
 
 /** Unit tests for {@link Spec11RegistrarThreatMatchesParser}. */
-@RunWith(JUnit4.class)
-public class Spec11RegistrarThreatMatchesParserTest {
+class Spec11RegistrarThreatMatchesParserTest {
 
   private static final String TODAY = "2018-07-21";
   private static final String YESTERDAY = "2018-07-20";
@@ -46,31 +43,31 @@ public class Spec11RegistrarThreatMatchesParserTest {
   private final Spec11RegistrarThreatMatchesParser parser =
       new Spec11RegistrarThreatMatchesParser(gcsUtils, "test-bucket");
 
-  @Before
-  public void setUp() {
+  @BeforeEach
+  void beforeEach() {
     setupFile("spec11_fake_report", TODAY);
   }
 
   @Test
-  public void testSuccess_retrievesReport() throws Exception {
+  void testSuccess_retrievesReport() throws Exception {
     assertThat(parser.getRegistrarThreatMatches(LocalDate.parse(TODAY)))
         .isEqualTo(sampleThreatMatches());
   }
 
   @Test
-  public void testFindPrevious_exists() throws Exception {
+  void testFindPrevious_exists() throws Exception {
     setupFile("spec11_fake_report_previous_day", YESTERDAY);
     assertThat(parser.getPreviousDateWithMatches(LocalDate.parse(TODAY)))
         .hasValue(LocalDate.parse(YESTERDAY));
   }
 
   @Test
-  public void testFindPrevious_notFound() {
+  void testFindPrevious_notFound() {
     assertThat(parser.getPreviousDateWithMatches(LocalDate.parse(TODAY))).isEmpty();
   }
 
   @Test
-  public void testFindPrevious_olderThanYesterdayFound() throws Exception {
+  void testFindPrevious_olderThanYesterdayFound() throws Exception {
     setupFile("spec11_fake_report_previous_day", "2018-07-14");
 
     assertThat(parser.getPreviousDateWithMatches(LocalDate.parse(TODAY)))
@@ -78,7 +75,7 @@ public class Spec11RegistrarThreatMatchesParserTest {
   }
 
   @Test
-  public void testSuccess_ignoreExtraFields() throws Exception {
+  void testSuccess_ignoreExtraFields() throws Exception {
     ThreatMatch objectWithExtraFields =
         ThreatMatch.fromJSON(
             new JSONObject(

core/src/test/java/google/registry/request/JsonResponseTest.java

@@ -21,25 +21,22 @@ import com.google.common.collect.ImmutableMap;
 import google.registry.testing.FakeResponse;
 import java.util.Map;
 import org.json.simple.JSONValue;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
 
 /** Unit tests for {@link JsonResponse}. */
-@RunWith(JUnit4.class)
-public class JsonResponseTest {
+class JsonResponseTest {
 
-  FakeResponse fakeResponse = new FakeResponse();
-  JsonResponse jsonResponse = new JsonResponse(fakeResponse);
+  private FakeResponse fakeResponse = new FakeResponse();
+  private JsonResponse jsonResponse = new JsonResponse(fakeResponse);
 
   @Test
-  public void testSetStatus() {
+  void testSetStatus() {
     jsonResponse.setStatus(666);
     assertThat(fakeResponse.getStatus()).isEqualTo(666);
   }
 
   @Test
-  public void testSetResponseValue() {
+  void testSetResponseValue() {
     ImmutableMap<String, String> responseValues = ImmutableMap.of(
         "hello", "world",
         "goodbye", "cruel world");
@@ -53,7 +50,7 @@ public class JsonResponseTest {
   }
 
   @Test
-  public void testSetHeader() {
+  void testSetHeader() {
     jsonResponse.setHeader("header", "value");
     Map<String, Object> headerMap = fakeResponse.getHeaders();
     assertThat(headerMap.size()).isEqualTo(1);

core/src/test/java/google/registry/request/RequestHandlerTest.java

@@ -42,19 +42,16 @@ import java.io.StringWriter;
 import java.util.Optional;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
-import org.junit.After;
-import org.junit.Before;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
 
 /** Unit tests for {@link RequestHandler}. */
-@RunWith(JUnit4.class)
 public final class RequestHandlerTest {
 
-  @Rule
-  public final AppEngineRule appEngine =
+  @RegisterExtension
+  final AppEngineRule appEngine =
       AppEngineRule.builder()
           .withDatastoreAndCloudSql()
           .withUserService(UserInfo.create("test@example.com", "test@example.com"))
@@ -102,7 +99,7 @@ public final class RequestHandlerTest {
 
   @Action(service = Action.Service.DEFAULT, path = "/failAtConstruction", auth = AUTH_PUBLIC)
   public static final class FailAtConstructionTask implements Runnable {
-    public FailAtConstructionTask() {
+    FailAtConstructionTask() {
       throw new ServiceUnavailableException("Fail at construction");
     }
 
@@ -207,8 +204,8 @@ public final class RequestHandlerTest {
   private AuthResult providedAuthResult = null;
   private final User testUser = new User("test@example.com", "test@example.com");
 
-  @Before
-  public void before() throws Exception {
+  @BeforeEach
+  void beforeEach() throws Exception {
     // Initialize here, not inline, so that we pick up the mocked UserService.
     handler =
         RequestHandler.createForTest(
@@ -226,8 +223,8 @@ public final class RequestHandlerTest {
     handler.requestMetrics = requestMetrics;
   }
 
-  @After
-  public void after() {
+  @AfterEach
+  void afterEach() {
     verifyNoMoreInteractions(rsp, bumblebeeTask, slothTask, safeSlothTask, requestMetrics);
   }
 
@@ -237,7 +234,7 @@ public final class RequestHandlerTest {
   }
 
   @Test
-  public void testHandleRequest_normalRequest_works() throws Exception {
+  void testHandleRequest_normalRequest_works() throws Exception {
     when(req.getMethod()).thenReturn("GET");
     when(req.getRequestURI()).thenReturn("/bumblebee");
     when(requestAuthenticator.authorize(AUTH_PUBLIC.authSettings(), req))
@@ -251,7 +248,7 @@ public final class RequestHandlerTest {
   }
 
   @Test
-  public void testHandleRequest_multipleMethodMappings_works() throws Exception {
+  void testHandleRequest_multipleMethodMappings_works() throws Exception {
     when(req.getMethod()).thenReturn("POST");
     when(req.getRequestURI()).thenReturn("/bumblebee");
     when(requestAuthenticator.authorize(AUTH_PUBLIC.authSettings(), req))
@@ -264,7 +261,7 @@ public final class RequestHandlerTest {
   }
 
   @Test
-  public void testHandleRequest_prefixEnabled_subpathsWork() throws Exception {
+  void testHandleRequest_prefixEnabled_subpathsWork() throws Exception {
     when(req.getMethod()).thenReturn("GET");
     when(req.getRequestURI()).thenReturn("/bumblebee/hive");
     when(requestAuthenticator.authorize(AUTH_PUBLIC.authSettings(), req))
@@ -277,7 +274,7 @@ public final class RequestHandlerTest {
   }
 
   @Test
-  public void testHandleRequest_taskHasAutoPrintOk_printsOk() throws Exception {
+  void testHandleRequest_taskHasAutoPrintOk_printsOk() throws Exception {
     when(req.getMethod()).thenReturn("POST");
     when(req.getRequestURI()).thenReturn("/sloth");
     when(requestAuthenticator.authorize(AUTH_PUBLIC.authSettings(), req))
@@ -293,7 +290,7 @@ public final class RequestHandlerTest {
   }
 
   @Test
-  public void testHandleRequest_prefixDisabled_subpathsReturn404NotFound() throws Exception {
+  void testHandleRequest_prefixDisabled_subpathsReturn404NotFound() throws Exception {
     when(req.getMethod()).thenReturn("POST");
     when(req.getRequestURI()).thenReturn("/sloth/nest");
     when(requestAuthenticator.authorize(AUTH_PUBLIC.authSettings(), req))
@@ -305,7 +302,7 @@ public final class RequestHandlerTest {
   }
 
   @Test
-  public void testHandleRequest_taskThrowsHttpException_getsHandledByHandler() throws Exception {
+  void testHandleRequest_taskThrowsHttpException_getsHandledByHandler() throws Exception {
     when(req.getMethod()).thenReturn("GET");
     when(req.getRequestURI()).thenReturn("/fail");
     when(requestAuthenticator.authorize(AUTH_PUBLIC.authSettings(), req))
@@ -319,7 +316,7 @@ public final class RequestHandlerTest {
 
   /** Test for a regression of the issue in b/21377705. */
   @Test
-  public void testHandleRequest_taskThrowsHttpException_atConstructionTime_getsHandledByHandler()
+  void testHandleRequest_taskThrowsHttpException_atConstructionTime_getsHandledByHandler()
       throws Exception {
     when(req.getMethod()).thenReturn("GET");
     when(req.getRequestURI()).thenReturn("/failAtConstruction");
@@ -333,7 +330,7 @@ public final class RequestHandlerTest {
   }
 
   @Test
-  public void testHandleRequest_notFound_returns404NotFound() throws Exception {
+  void testHandleRequest_notFound_returns404NotFound() throws Exception {
     when(req.getMethod()).thenReturn("GET");
     when(req.getRequestURI()).thenReturn("/bogus");
     when(requestAuthenticator.authorize(AUTH_PUBLIC.authSettings(), req))
@@ -345,7 +342,7 @@ public final class RequestHandlerTest {
   }
 
   @Test
-  public void testHandleRequest_methodNotAllowed_returns405MethodNotAllowed() throws Exception {
+  void testHandleRequest_methodNotAllowed_returns405MethodNotAllowed() throws Exception {
     when(req.getMethod()).thenReturn("POST");
     when(req.getRequestURI()).thenReturn("/fail");
     when(requestAuthenticator.authorize(AUTH_PUBLIC.authSettings(), req))
@@ -357,7 +354,7 @@ public final class RequestHandlerTest {
   }
 
   @Test
-  public void testHandleRequest_insaneMethod_returns405MethodNotAllowed() throws Exception {
+  void testHandleRequest_insaneMethod_returns405MethodNotAllowed() throws Exception {
     when(req.getMethod()).thenReturn("FIREAWAY");
     when(req.getRequestURI()).thenReturn("/fail");
     when(requestAuthenticator.authorize(AUTH_PUBLIC.authSettings(), req))
@@ -368,10 +365,12 @@ public final class RequestHandlerTest {
     verify(rsp).sendError(405);
   }
 
-  /** @see <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec5.html#sec5.1.1">
-   *     RFC2616 - HTTP/1.1 - Method</a> */
+  /**
+   * @see <a href="http://www.w3.org/Protocols/rfc2616/rfc2616-sec5.html#sec5.1.1">RFC2616 -
+   *     HTTP/1.1 - Method</a>
+   */
   @Test
-  public void testHandleRequest_lowercaseMethod_notRecognized() throws Exception {
+  void testHandleRequest_lowercaseMethod_notRecognized() throws Exception {
     when(req.getMethod()).thenReturn("get");
     when(req.getRequestURI()).thenReturn("/bumblebee");
     when(requestAuthenticator.authorize(AUTH_PUBLIC.authSettings(), req))
@@ -382,8 +381,9 @@ public final class RequestHandlerTest {
     verify(rsp).sendError(405);
   }
 
+  @SuppressWarnings("UnstableApiUsage")
   @Test
-  public void testNullness() {
+  void testNullness() {
     NullPointerTester tester = new NullPointerTester();
     tester.setDefault(Class.class, Component.class);
     tester.setDefault(RequestAuthenticator.class, requestAuthenticator);
@@ -392,7 +392,7 @@ public final class RequestHandlerTest {
   }
 
   @Test
-  public void testXsrfProtection_validTokenProvided_runsAction() throws Exception {
+  void testXsrfProtection_validTokenProvided_runsAction() throws Exception {
     when(req.getMethod()).thenReturn("POST");
     when(req.getRequestURI()).thenReturn("/safe-sloth");
     when(requestAuthenticator.authorize(AUTH_PUBLIC.authSettings(), req))
@@ -405,7 +405,7 @@ public final class RequestHandlerTest {
   }
 
   @Test
-  public void testXsrfProtection_GETMethodWithoutToken_doesntCheckToken() throws Exception {
+  void testXsrfProtection_GETMethodWithoutToken_doesntCheckToken() throws Exception {
     when(req.getMethod()).thenReturn("GET");
     when(req.getRequestURI()).thenReturn("/safe-sloth");
     when(requestAuthenticator.authorize(AUTH_PUBLIC.authSettings(), req))
@@ -418,7 +418,7 @@ public final class RequestHandlerTest {
   }
 
   @Test
-  public void testNoAuthNeeded_success() throws Exception {
+  void testNoAuthNeeded_success() throws Exception {
     when(req.getMethod()).thenReturn("GET");
     when(req.getRequestURI()).thenReturn("/auth/none");
     when(requestAuthenticator.authorize(AUTH_PUBLIC.authSettings(), req))
@@ -433,7 +433,7 @@ public final class RequestHandlerTest {
   }
 
   @Test
-  public void testAuthNeeded_failure() throws Exception {
+  void testAuthNeeded_failure() throws Exception {
     when(req.getMethod()).thenReturn("GET");
     when(req.getRequestURI()).thenReturn("/auth/adminUser");
     when(requestAuthenticator.authorize(AUTH_INTERNAL_OR_ADMIN.authSettings(), req))
@@ -446,7 +446,7 @@ public final class RequestHandlerTest {
   }
 
   @Test
-  public void testAuthNeeded_success() throws Exception {
+  void testAuthNeeded_success() throws Exception {
     when(req.getMethod()).thenReturn("GET");
     when(req.getRequestURI()).thenReturn("/auth/adminUser");
     when(requestAuthenticator.authorize(AUTH_INTERNAL_OR_ADMIN.authSettings(), req))
@@ -462,5 +462,4 @@ public final class RequestHandlerTest {
     assertThat(providedAuthResult.userAuthInfo().get().oauthTokenInfo()).isEmpty();
     assertMetric("/auth/adminUser", GET, AuthLevel.USER, true);
   }
-
 }

core/src/test/java/google/registry/request/RequestModuleTest.java

@@ -21,27 +21,24 @@ import static org.junit.Assert.assertThrows;
 import com.google.common.net.MediaType;
 import google.registry.request.HttpException.BadRequestException;
 import google.registry.request.HttpException.UnsupportedMediaTypeException;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
 
 /** Unit tests for {@link RequestModule}. */
-@RunWith(JUnit4.class)
-public final class RequestModuleTest {
+final class RequestModuleTest {
+
   @Test
-  public void testProvideJsonPayload() {
-    assertThat(provideJsonPayload(MediaType.JSON_UTF_8, "{\"k\":\"v\"}"))
-        .containsExactly("k", "v");
+  void testProvideJsonPayload() {
+    assertThat(provideJsonPayload(MediaType.JSON_UTF_8, "{\"k\":\"v\"}")).containsExactly("k", "v");
   }
 
   @Test
-  public void testProvideJsonPayload_contentTypeWithoutCharsetAllowed() {
+  void testProvideJsonPayload_contentTypeWithoutCharsetAllowed() {
     assertThat(provideJsonPayload(MediaType.JSON_UTF_8.withoutParameters(), "{\"k\":\"v\"}"))
         .containsExactly("k", "v");
   }
 
   @Test
-  public void testProvideJsonPayload_malformedInput_throws500() {
+  void testProvideJsonPayload_malformedInput_throws500() {
     BadRequestException thrown =
         assertThrows(
             BadRequestException.class, () -> provideJsonPayload(MediaType.JSON_UTF_8, "{\"k\":"));
@@ -49,21 +46,21 @@ public final class RequestModuleTest {
   }
 
   @Test
-  public void testProvideJsonPayload_emptyInput_throws500() {
+  void testProvideJsonPayload_emptyInput_throws500() {
     BadRequestException thrown =
         assertThrows(BadRequestException.class, () -> provideJsonPayload(MediaType.JSON_UTF_8, ""));
     assertThat(thrown).hasMessageThat().contains("Malformed JSON");
   }
 
   @Test
-  public void testProvideJsonPayload_nonJsonContentType_throws415() {
+  void testProvideJsonPayload_nonJsonContentType_throws415() {
     assertThrows(
         UnsupportedMediaTypeException.class,
         () -> provideJsonPayload(MediaType.PLAIN_TEXT_UTF_8, "{}"));
   }
 
   @Test
-  public void testProvideJsonPayload_contentTypeWithWeirdParam_throws415() {
+  void testProvideJsonPayload_contentTypeWithWeirdParam_throws415() {
     assertThrows(
         UnsupportedMediaTypeException.class,
         () -> provideJsonPayload(MediaType.JSON_UTF_8.withParameter("omg", "handel"), "{}"));

core/src/test/java/google/registry/request/RequestParametersTest.java

@@ -33,30 +33,28 @@ import com.google.common.collect.ImmutableMap;
 import google.registry.request.HttpException.BadRequestException;
 import javax.servlet.http.HttpServletRequest;
 import org.joda.time.DateTime;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
 
 /** Unit tests for {@link RequestParameters}. */
-@RunWith(JUnit4.class)
-public class RequestParametersTest {
+class RequestParametersTest {
+
   private final HttpServletRequest req = mock(HttpServletRequest.class);
 
   @Test
-  public void testExtractRequiredParameter_valuePresent_returnsValue() {
+  void testExtractRequiredParameter_valuePresent_returnsValue() {
     when(req.getParameter("spin")).thenReturn("bog");
     assertThat(extractRequiredParameter(req, "spin")).isEqualTo("bog");
   }
 
   @Test
-  public void testExtractRequiredParameter_notPresent_throwsBadRequest() {
+  void testExtractRequiredParameter_notPresent_throwsBadRequest() {
     BadRequestException thrown =
         assertThrows(BadRequestException.class, () -> extractRequiredParameter(req, "spin"));
     assertThat(thrown).hasMessageThat().contains("spin");
   }
 
   @Test
-  public void testExtractRequiredParameter_empty_throwsBadRequest() {
+  void testExtractRequiredParameter_empty_throwsBadRequest() {
     when(req.getParameter("spin")).thenReturn("");
     BadRequestException thrown =
         assertThrows(BadRequestException.class, () -> extractRequiredParameter(req, "spin"));
@@ -64,100 +62,100 @@ public class RequestParametersTest {
   }
 
   @Test
-  public void testExtractOptionalParameter_valuePresent_returnsValue() {
+  void testExtractOptionalParameter_valuePresent_returnsValue() {
     when(req.getParameter("spin")).thenReturn("bog");
     assertThat(extractOptionalParameter(req, "spin")).hasValue("bog");
   }
 
   @Test
-  public void testExtractOptionalParameter_notPresent_returnsEmpty() {
+  void testExtractOptionalParameter_notPresent_returnsEmpty() {
     assertThat(extractOptionalParameter(req, "spin")).isEmpty();
   }
 
   @Test
-  public void testExtractOptionalParameter_empty_returnsEmpty() {
+  void testExtractOptionalParameter_empty_returnsEmpty() {
     when(req.getParameter("spin")).thenReturn("");
     assertThat(extractOptionalParameter(req, "spin")).isEmpty();
   }
 
   @Test
-  public void testExtractSetOfParameters_notPresent_returnsEmpty() {
+  void testExtractSetOfParameters_notPresent_returnsEmpty() {
     assertThat(extractSetOfParameters(req, "spin")).isEmpty();
   }
 
   @Test
-  public void testExtractSetOfParameters_empty_returnsEmpty() {
+  void testExtractSetOfParameters_empty_returnsEmpty() {
     when(req.getParameter("spin")).thenReturn("");
     assertThat(extractSetOfParameters(req, "spin")).isEmpty();
   }
 
   @Test
-  public void testExtractSetOfParameters_oneValue_returnsValue() {
+  void testExtractSetOfParameters_oneValue_returnsValue() {
     when(req.getParameter("spin")).thenReturn("bog");
     assertThat(extractSetOfParameters(req, "spin")).containsExactly("bog");
   }
 
   @Test
-  public void testExtractSetOfParameters_multipleValues_returnsAll() {
+  void testExtractSetOfParameters_multipleValues_returnsAll() {
     when(req.getParameter("spin")).thenReturn("bog,gob");
     assertThat(extractSetOfParameters(req, "spin")).containsExactly("bog", "gob");
   }
 
   @Test
-  public void testExtractSetOfParameters_multipleValuesWithEmpty_removesEmpty() {
+  void testExtractSetOfParameters_multipleValuesWithEmpty_removesEmpty() {
     when(req.getParameter("spin")).thenReturn(",bog,,gob,");
     assertThat(extractSetOfParameters(req, "spin")).containsExactly("bog", "gob");
   }
 
   @Test
-  public void testExtractSetOfParameters_multipleParameters_error() {
-    when(req.getParameterValues("spin")).thenReturn(new String[]{"bog", "gob"});
+  void testExtractSetOfParameters_multipleParameters_error() {
+    when(req.getParameterValues("spin")).thenReturn(new String[] {"bog", "gob"});
     BadRequestException thrown =
         assertThrows(BadRequestException.class, () -> extractSetOfParameters(req, "spin"));
     assertThat(thrown).hasMessageThat().contains("spin");
   }
 
   @Test
-  public void testExtractSetOfEnumParameters_notPresent_returnsEmpty() {
+  void testExtractSetOfEnumParameters_notPresent_returnsEmpty() {
     assertThat(extractSetOfEnumParameters(req, Club.class, "spin")).isEmpty();
   }
 
   @Test
-  public void testExtractSetOfEnumParameters_empty_returnsEmpty() {
+  void testExtractSetOfEnumParameters_empty_returnsEmpty() {
     when(req.getParameter("spin")).thenReturn("");
     assertThat(extractSetOfEnumParameters(req, Club.class, "spin")).isEmpty();
   }
 
   @Test
-  public void testExtractSetOfEnumParameters_oneValue_returnsValue() {
+  void testExtractSetOfEnumParameters_oneValue_returnsValue() {
     when(req.getParameter("spin")).thenReturn("DANCE");
     assertThat(extractSetOfEnumParameters(req, Club.class, "spin")).containsExactly(Club.DANCE);
   }
 
   @Test
-  public void testExtractSetOfEnumParameters_multipleValues_returnsAll() {
+  void testExtractSetOfEnumParameters_multipleValues_returnsAll() {
     when(req.getParameter("spin")).thenReturn("DANCE,FLOOR");
     assertThat(extractSetOfEnumParameters(req, Club.class, "spin"))
         .containsExactly(Club.DANCE, Club.FLOOR);
   }
 
   @Test
-  public void testExtractSetOfEnumParameters_multipleValuesWithEmpty_removesEmpty() {
+  void testExtractSetOfEnumParameters_multipleValuesWithEmpty_removesEmpty() {
     when(req.getParameter("spin")).thenReturn(",DANCE,,FLOOR,");
     assertThat(extractSetOfEnumParameters(req, Club.class, "spin"))
         .containsExactly(Club.DANCE, Club.FLOOR);
   }
 
   @Test
-  public void testExtractSetOfEnumParameters_multipleValues_caseInsensitive() {
+  void testExtractSetOfEnumParameters_multipleValues_caseInsensitive() {
     when(req.getParameter("spin")).thenReturn("danCE,FlooR");
     assertThat(extractSetOfEnumParameters(req, Club.class, "spin"))
         .containsExactly(Club.DANCE, Club.FLOOR);
   }
 
   @Test
-  public void testExtractSetOfEnumParameters_multipleParameters_error() {
-    when(req.getParameterValues("spin")).thenReturn(new String[]{"DANCE", "FLOOR"});
+  void testExtractSetOfEnumParameters_multipleParameters_error() {
+    when(req.getParameterValues("spin")).thenReturn(new String[] {"DANCE", "FLOOR"});
     BadRequestException thrown =
         assertThrows(
             BadRequestException.class, () -> extractSetOfEnumParameters(req, Club.class, "spin"));
@@ -165,67 +163,70 @@ public class RequestParametersTest {
   }
 
   @Test
-  public void testExtractBooleanParameter_notPresent_returnsFalse() {
+  void testExtractBooleanParameter_notPresent_returnsFalse() {
     assertThat(extractBooleanParameter(req, "love")).isFalse();
   }
 
   @Test
-  public void testExtractBooleanParameter_presentWithoutValue_returnsTrue() {
+  void testExtractBooleanParameter_presentWithoutValue_returnsTrue() {
     when(req.getParameterMap()).thenReturn(ImmutableMap.of("love", ""));
     assertThat(extractBooleanParameter(req, "love")).isTrue();
   }
 
   @Test
-  public void testExtractBooleanParameter_empty_returnsTrue() {
+  void testExtractBooleanParameter_empty_returnsTrue() {
     when(req.getParameterMap()).thenReturn(ImmutableMap.of("love", ""));
     when(req.getParameter("love")).thenReturn("");
     assertThat(extractBooleanParameter(req, "love")).isTrue();
   }
 
   @Test
-  public void testExtractBooleanParameter_presentStringArbitrary_returnsTrue() {
+  void testExtractBooleanParameter_presentStringArbitrary_returnsTrue() {
     when(req.getParameterMap()).thenReturn(ImmutableMap.of("love", "lol"));
     when(req.getParameter("love")).thenReturn("lol");
     assertThat(extractBooleanParameter(req, "love")).isTrue();
   }
 
   @Test
-  public void testExtractBooleanParameter_presentStringTrue_returnsTrue() {
+  void testExtractBooleanParameter_presentStringTrue_returnsTrue() {
     when(req.getParameterMap()).thenReturn(ImmutableMap.of("love", "true"));
     when(req.getParameter("love")).thenReturn("true");
     assertThat(extractBooleanParameter(req, "love")).isTrue();
   }
 
   @Test
-  public void testExtractBooleanParameter_presentStringFalse_returnsFalse() {
+  void testExtractBooleanParameter_presentStringFalse_returnsFalse() {
     when(req.getParameterMap()).thenReturn(ImmutableMap.of("love", "false"));
     when(req.getParameter("love")).thenReturn("false");
     assertThat(extractBooleanParameter(req, "love")).isFalse();
   }
 
   @Test
-  public void testExtractBooleanParameter_presentStringFalse_caseInsensitive() {
+  void testExtractBooleanParameter_presentStringFalse_caseInsensitive() {
     when(req.getParameterMap()).thenReturn(ImmutableMap.of("love", "FaLsE"));
     when(req.getParameter("love")).thenReturn("FaLsE");
     assertThat(extractBooleanParameter(req, "love")).isFalse();
   }
 
-  enum Club { DANCE, FLOOR }
+  enum Club {
+    DANCE,
+    FLOOR
+  }
 
   @Test
-  public void testExtractEnumValue_correctValue_works() {
+  void testExtractEnumValue_correctValue_works() {
     when(req.getParameter("spin")).thenReturn("DANCE");
     assertThat(extractEnumParameter(req, Club.class, "spin")).isEqualTo(Club.DANCE);
   }
 
   @Test
-  public void testExtractEnumValue_weirdCasing_isCaseInsensitive() {
+  void testExtractEnumValue_weirdCasing_isCaseInsensitive() {
     when(req.getParameter("spin")).thenReturn("DaNcE");
     assertThat(extractEnumParameter(req, Club.class, "spin")).isEqualTo(Club.DANCE);
   }
 
   @Test
-  public void testExtractEnumValue_nonExistentValue_throwsBadRequest() {
+  void testExtractEnumValue_nonExistentValue_throwsBadRequest() {
     when(req.getParameter("spin")).thenReturn("sing");
     BadRequestException thrown =
         assertThrows(
@@ -234,19 +235,19 @@ public class RequestParametersTest {
   }
 
   @Test
-  public void testOptionalExtractEnumValue_givenValue_returnsValue() {
+  void testOptionalExtractEnumValue_givenValue_returnsValue() {
     when(req.getParameter("spin")).thenReturn("DANCE");
     assertThat(extractOptionalEnumParameter(req, Club.class, "spin")).hasValue(Club.DANCE);
   }
 
   @Test
-  public void testOptionalExtractEnumValue_noValue_returnsEmpty() {
+  void testOptionalExtractEnumValue_noValue_returnsEmpty() {
     when(req.getParameter("spin")).thenReturn("");
     assertThat(extractOptionalEnumParameter(req, Club.class, "spin")).isEmpty();
   }
 
   @Test
-  public void testOptionalExtractEnumValue_nonExistentValue_throwsBadRequest() {
+  void testOptionalExtractEnumValue_nonExistentValue_throwsBadRequest() {
     when(req.getParameter("spin")).thenReturn("sing");
     BadRequestException thrown =
         assertThrows(
@@ -255,14 +256,14 @@ public class RequestParametersTest {
   }
 
   @Test
-  public void testExtractRequiredDatetimeParameter_correctValue_works() {
+  void testExtractRequiredDatetimeParameter_correctValue_works() {
     when(req.getParameter("timeParam")).thenReturn("2015-08-27T13:25:34.123Z");
     assertThat(extractRequiredDatetimeParameter(req, "timeParam"))
         .isEqualTo(DateTime.parse("2015-08-27T13:25:34.123Z"));
   }
 
   @Test
-  public void testExtractRequiredDatetimeParameter_badValue_throwsBadRequest() {
+  void testExtractRequiredDatetimeParameter_badValue_throwsBadRequest() {
     when(req.getParameter("timeParam")).thenReturn("Tuesday at three o'clock");
     BadRequestException thrown =
         assertThrows(
@@ -271,14 +272,14 @@ public class RequestParametersTest {
   }
 
   @Test
-  public void testExtractOptionalDatetimeParameter_correctValue_works() {
+  void testExtractOptionalDatetimeParameter_correctValue_works() {
     when(req.getParameter("timeParam")).thenReturn("2015-08-27T13:25:34.123Z");
     assertThat(extractOptionalDatetimeParameter(req, "timeParam"))
         .hasValue(DateTime.parse("2015-08-27T13:25:34.123Z"));
   }
 
   @Test
-  public void testExtractOptionalDatetimeParameter_badValue_throwsBadRequest() {
+  void testExtractOptionalDatetimeParameter_badValue_throwsBadRequest() {
     when(req.getParameter("timeParam")).thenReturn("Tuesday at three o'clock");
     BadRequestException thrown =
         assertThrows(
@@ -287,13 +288,13 @@ public class RequestParametersTest {
   }
 
   @Test
-  public void testExtractOptionalDatetimeParameter_empty_returnsEmpty() {
+  void testExtractOptionalDatetimeParameter_empty_returnsEmpty() {
     when(req.getParameter("timeParam")).thenReturn("");
     assertThat(extractOptionalDatetimeParameter(req, "timeParam")).isEmpty();
   }
 
   @Test
-  public void testExtractRequiredDatetimeParameter_noValue_throwsBadRequest() {
+  void testExtractRequiredDatetimeParameter_noValue_throwsBadRequest() {
     BadRequestException thrown =
         assertThrows(
             BadRequestException.class, () -> extractRequiredDatetimeParameter(req, "timeParam"));

core/src/test/java/google/registry/request/ResponseImplTest.java

@@ -24,32 +24,29 @@ import static org.mockito.Mockito.when;
 import java.io.PrintWriter;
 import java.io.StringWriter;
 import javax.servlet.http.HttpServletResponse;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
 
 /** Unit tests for {@link ResponseImpl}. */
-@RunWith(JUnit4.class)
-public class ResponseImplTest {
+class ResponseImplTest {
 
   private final HttpServletResponse rsp = mock(HttpServletResponse.class);
 
   @Test
-  public void testSetStatus() {
+  void testSetStatus() {
     new ResponseImpl(rsp).setStatus(666);
     verify(rsp).setStatus(666);
     verifyNoMoreInteractions(rsp);
   }
 
   @Test
-  public void testSetContentType() {
+  void testSetContentType() {
     new ResponseImpl(rsp).setContentType(PLAIN_TEXT_UTF_8);
     verify(rsp).setContentType("text/plain; charset=utf-8");
     verifyNoMoreInteractions(rsp);
   }
 
   @Test
-  public void testSetPayload() throws Exception {
+  void testSetPayload() throws Exception {
     StringWriter httpOutput = new StringWriter();
     when(rsp.getWriter()).thenReturn(new PrintWriter(httpOutput));
     new ResponseImpl(rsp).setPayload("hello world");

core/src/test/java/google/registry/request/RouterTest.java

@@ -22,12 +22,9 @@ import static org.junit.Assert.assertThrows;
 import java.util.Optional;
 import java.util.concurrent.Callable;
 import java.util.function.Function;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
 
 /** Unit tests for {@link Router}. */
-@RunWith(JUnit4.class)
 public final class RouterTest {
 
   ////////////////////////////////////////////////////////////////////////////////////////////////
@@ -35,7 +32,7 @@ public final class RouterTest {
   public interface Empty {}
 
   @Test
-  public void testRoute_noRoutes_throws() {
+  void testRoute_noRoutes_throws() {
     IllegalArgumentException thrown =
         assertThrows(IllegalArgumentException.class, () -> Router.create(Empty.class));
     assertThat(thrown)
@@ -56,7 +53,7 @@ public final class RouterTest {
   }
 
   @Test
-  public void testRoute_pathMatch_returnsRoute() {
+  void testRoute_pathMatch_returnsRoute() {
     Optional<Route> route = Router.create(SlothComponent.class).route("/sloth");
     assertThat(route).isPresent();
     assertThat(route.get().action().path()).isEqualTo("/sloth");
@@ -64,12 +61,12 @@ public final class RouterTest {
   }
 
   @Test
-  public void testRoute_pathMismatch_returnsEmpty() {
+  void testRoute_pathMismatch_returnsEmpty() {
     assertThat(Router.create(SlothComponent.class).route("/doge")).isEmpty();
   }
 
   @Test
-  public void testRoute_pathIsAPrefix_notAllowedByDefault() {
+  void testRoute_pathIsAPrefix_notAllowedByDefault() {
     assertThat(Router.create(SlothComponent.class).route("/sloth/extra")).isEmpty();
   }
 
@@ -90,13 +87,13 @@ public final class RouterTest {
   }
 
   @Test
-  public void testRoute_prefixMatches_returnsRoute() {
+  void testRoute_prefixMatches_returnsRoute() {
     assertThat(Router.create(PrefixComponent.class).route("/prefix")).isPresent();
     assertThat(Router.create(PrefixComponent.class).route("/prefix/extra")).isPresent();
   }
 
   @Test
-  public void testRoute_prefixDoesNotMatch_returnsEmpty() {
+  void testRoute_prefixDoesNotMatch_returnsEmpty() {
     assertThat(Router.create(PrefixComponent.class).route("")).isEmpty();
     assertThat(Router.create(PrefixComponent.class).route("/")).isEmpty();
     assertThat(Router.create(PrefixComponent.class).route("/ulysses")).isEmpty();
@@ -121,21 +118,21 @@ public final class RouterTest {
   }
 
   @Test
-  public void testRoute_prefixAndLongPathMatch_returnsLongerPath() {
+  void testRoute_prefixAndLongPathMatch_returnsLongerPath() {
     Optional<Route> route = Router.create(LongPathComponent.class).route("/prefix/long");
     assertThat(route).isPresent();
     assertThat(route.get().action().path()).isEqualTo("/prefix/long");
   }
 
   @Test
-  public void testRoute_prefixAndLongerPrefixMatch_returnsLongerPrefix() {
+  void testRoute_prefixAndLongerPrefixMatch_returnsLongerPrefix() {
     Optional<Route> route = Router.create(LongPathComponent.class).route("/prefix/longer");
     assertThat(route).isPresent();
     assertThat(route.get().action().path()).isEqualTo("/prefix/long");
   }
 
   @Test
-  public void testRoute_onlyShortPrefixMatches_returnsShortPrefix() {
+  void testRoute_onlyShortPrefixMatches_returnsShortPrefix() {
     Optional<Route> route = Router.create(LongPathComponent.class).route("/prefix/cat");
     assertThat(route).isPresent();
     assertThat(route.get().action().path()).isEqualTo("/prefix");
@@ -149,7 +146,7 @@ public final class RouterTest {
   }
 
   @Test
-  public void testRoute_methodsInComponentAreIgnored_throws() {
+  void testRoute_methodsInComponentAreIgnored_throws() {
     IllegalArgumentException thrown =
         assertThrows(
             IllegalArgumentException.class, () -> Router.create(WeirdMethodsComponent.class));
@@ -185,7 +182,7 @@ public final class RouterTest {
   }
 
   @Test
-  public void testCreate_twoTasksWithSameMethodAndPath_resultsInError() {
+  void testCreate_twoTasksWithSameMethodAndPath_resultsInError() {
     IllegalArgumentException thrown =
         assertThrows(IllegalArgumentException.class, () -> Router.create(DuplicateComponent.class));
     assertThat(thrown).hasMessageThat().contains("Multiple entries with same key");

core/src/test/java/google/registry/request/auth/AuthTest.java

@@ -14,16 +14,13 @@
 
 package google.registry.request.auth;
 
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.Test;
 
 /** Unit tests for {@link Auth}. */
-@RunWith(JUnit4.class)
-public final class AuthTest {
+final class AuthTest {
 
   @Test
-  public void testAuthValues_validConfig() {
+  void testAuthValues_validConfig() {
     for (Auth auth : Auth.values()) {
       RequestAuthenticator.checkAuthConfig(auth.authSettings());
     }

core/src/test/java/google/registry/request/auth/AuthenticatedRegistrarAccessorTest.java

@@ -43,25 +43,25 @@ import java.util.Optional;
 import java.util.logging.Level;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
-import org.junit.After;
-import org.junit.Before;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.junit.jupiter.api.extension.RegisterExtension;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnit;
-import org.mockito.junit.MockitoRule;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.mockito.junit.jupiter.MockitoSettings;
+import org.mockito.quality.Strictness;
 
 /** Unit tests for {@link AuthenticatedRegistrarAccessor}. */
-@RunWith(JUnit4.class)
-public class AuthenticatedRegistrarAccessorTest {
+@ExtendWith(MockitoExtension.class)
+@MockitoSettings(strictness = Strictness.LENIENT)
+class AuthenticatedRegistrarAccessorTest {
 
-  @Rule
-  public final AppEngineRule appEngine = AppEngineRule.builder().withDatastoreAndCloudSql().build();
+  @RegisterExtension
+  final AppEngineRule appEngine = AppEngineRule.builder().withDatastoreAndCloudSql().build();
 
-  @Rule public final InjectRule inject = new InjectRule();
-  @Rule public final MockitoRule mocks = MockitoJUnit.rule();
+  @RegisterExtension final InjectRule inject = new InjectRule();
 
   @Mock private HttpServletRequest req;
   @Mock private HttpServletResponse rsp;
@@ -86,7 +86,7 @@ public class AuthenticatedRegistrarAccessorTest {
   /**
    * Creates an AuthResult for a fake user.
    *
-   * The user will be a RegistrarContact for "TheRegistrar", but not for "NewRegistrar".
+   * <p>The user will be a RegistrarContact for "TheRegistrar", but not for "NewRegistrar".
    *
    * @param isAdmin if true, the user is an administrator for the app-engine project.
    */
@@ -103,8 +103,8 @@ public class AuthenticatedRegistrarAccessorTest {
             isAdmin));
   }
 
-  @Before
-  public void before() {
+  @BeforeEach
+  void beforeEach() {
     when(lazyGroupsConnection.get()).thenReturn(groupsConnection);
     LoggerConfig.getConfig(AuthenticatedRegistrarAccessor.class).addHandler(testLogHandler);
     // persistResource(loadRegistrar(ADMIN_CLIENT_ID));
@@ -125,14 +125,14 @@ public class AuthenticatedRegistrarAccessorTest {
     when(groupsConnection.isMemberOfGroup(any(), any())).thenReturn(false);
   }
 
-  @After
-  public void after() {
+  @AfterEach
+  void afterEach() {
     LoggerConfig.getConfig(AuthenticatedRegistrarAccessor.class).removeHandler(testLogHandler);
   }
 
   /** Users are owners for registrars if and only if they are in the contacts for that registrar. */
   @Test
-  public void getAllClientIdWithAccess_user() {
+  void getAllClientIdWithAccess_user() {
     AuthenticatedRegistrarAccessor registrarAccessor =
         new AuthenticatedRegistrarAccessor(
             USER, ADMIN_CLIENT_ID, SUPPORT_GROUP, lazyGroupsConnection);
@@ -144,7 +144,7 @@ public class AuthenticatedRegistrarAccessorTest {
 
   /** Logged out users don't have access to anything. */
   @Test
-  public void getAllClientIdWithAccess_loggedOutUser() {
+  void getAllClientIdWithAccess_loggedOutUser() {
     AuthenticatedRegistrarAccessor registrarAccessor =
         new AuthenticatedRegistrarAccessor(
             NO_USER, ADMIN_CLIENT_ID, SUPPORT_GROUP, lazyGroupsConnection);
@@ -165,7 +165,7 @@ public class AuthenticatedRegistrarAccessorTest {
    * <p>(in other words - they don't have OWNER access only to REAL registrars owned by others)
    */
   @Test
-  public void getAllClientIdWithAccess_gaeAdmin() {
+  void getAllClientIdWithAccess_gaeAdmin() {
     AuthenticatedRegistrarAccessor registrarAccessor =
         new AuthenticatedRegistrarAccessor(
             GAE_ADMIN, ADMIN_CLIENT_ID, SUPPORT_GROUP, lazyGroupsConnection);
@@ -197,7 +197,7 @@ public class AuthenticatedRegistrarAccessorTest {
    * <p>(in other words - they don't have OWNER access only to REAL registrars owned by others)
    */
   @Test
-  public void getAllClientIdWithAccess_userInSupportGroup() {
+  void getAllClientIdWithAccess_userInSupportGroup() {
     when(groupsConnection.isMemberOfGroup("user@gmail.com", SUPPORT_GROUP.get())).thenReturn(true);
     AuthenticatedRegistrarAccessor registrarAccessor =
         new AuthenticatedRegistrarAccessor(
@@ -220,7 +220,7 @@ public class AuthenticatedRegistrarAccessorTest {
 
   /** Empty Support group email - skips check and doesn't generate the lazy. */
   @Test
-  public void getAllClientIdWithAccess_emptySupportEmail_works() {
+  void getAllClientIdWithAccess_emptySupportEmail_works() {
     AuthenticatedRegistrarAccessor registrarAccessor =
         new AuthenticatedRegistrarAccessor(
             USER, ADMIN_CLIENT_ID, Optional.empty(), lazyGroupsConnection);
@@ -233,7 +233,7 @@ public class AuthenticatedRegistrarAccessorTest {
 
   /** Support group check throws - continue anyway. */
   @Test
-  public void getAllClientIdWithAccess_throwingGroupCheck_stillWorks() {
+  void getAllClientIdWithAccess_throwingGroupCheck_stillWorks() {
     when(groupsConnection.isMemberOfGroup(any(), any())).thenThrow(new RuntimeException("blah"));
     AuthenticatedRegistrarAccessor registrarAccessor =
         new AuthenticatedRegistrarAccessor(
@@ -247,7 +247,7 @@ public class AuthenticatedRegistrarAccessorTest {
 
   /** Fail loading registrar if user doesn't have access to it. */
   @Test
-  public void testGetRegistrarForUser_noAccess_isNotAdmin() {
+  void testGetRegistrarForUser_noAccess_isNotAdmin() {
     expectGetRegistrarFailure(
         REAL_CLIENT_ID_WITHOUT_CONTACT,
         USER,
@@ -256,7 +256,7 @@ public class AuthenticatedRegistrarAccessorTest {
   }
 
   @Test
-  public void testGetRegistrarForUser_registrarIsDisabled_isNotAdmin() {
+  void testGetRegistrarForUser_registrarIsDisabled_isNotAdmin() {
     persistResource(
         Registrar.loadByClientId("TheRegistrar")
             .get()
@@ -272,7 +272,7 @@ public class AuthenticatedRegistrarAccessorTest {
 
   /** Fail loading registrar if user doesn't have access to it, even if it's not REAL. */
   @Test
-  public void testGetRegistrarForUser_noAccess_isNotAdmin_notReal() {
+  void testGetRegistrarForUser_noAccess_isNotAdmin_notReal() {
     expectGetRegistrarFailure(
         OTE_CLIENT_ID_WITHOUT_CONTACT,
         USER,
@@ -282,7 +282,7 @@ public class AuthenticatedRegistrarAccessorTest {
 
   /** Fail loading registrar if there's no user associated with the request. */
   @Test
-  public void testGetRegistrarForUser_noUser() {
+  void testGetRegistrarForUser_noUser() {
     expectGetRegistrarFailure(
         CLIENT_ID_WITH_CONTACT,
         NO_USER,
@@ -292,7 +292,7 @@ public class AuthenticatedRegistrarAccessorTest {
 
   /** Succeed loading registrar if user has access to it. */
   @Test
-  public void testGetRegistrarForUser_inContacts_isNotAdmin() throws Exception {
+  void testGetRegistrarForUser_inContacts_isNotAdmin() throws Exception {
     expectGetRegistrarSuccess(
         CLIENT_ID_WITH_CONTACT,
         USER,
@@ -302,7 +302,7 @@ public class AuthenticatedRegistrarAccessorTest {
 
   /** Succeed loading registrar if admin with access. */
   @Test
-  public void testGetRegistrarForUser_inContacts_isAdmin() throws Exception {
+  void testGetRegistrarForUser_inContacts_isAdmin() throws Exception {
     expectGetRegistrarSuccess(
         CLIENT_ID_WITH_CONTACT,
         GAE_ADMIN,
@@ -312,7 +312,7 @@ public class AuthenticatedRegistrarAccessorTest {
 
   /** Succeed loading registrar for admin even if they aren't on the approved contacts list. */
   @Test
-  public void testGetRegistrarForUser_notInContacts_isAdmin() throws Exception {
+  void testGetRegistrarForUser_notInContacts_isAdmin() throws Exception {
     expectGetRegistrarSuccess(
         REAL_CLIENT_ID_WITHOUT_CONTACT,
         GAE_ADMIN,
@@ -321,7 +321,7 @@ public class AuthenticatedRegistrarAccessorTest {
   }
 
   @Test
-  public void testGetRegistrarForUser_registrarIsDisabled_isAdmin() throws Exception {
+  void testGetRegistrarForUser_registrarIsDisabled_isAdmin() throws Exception {
     persistResource(
         Registrar.loadByClientId("NewRegistrar")
             .get()
@@ -337,7 +337,7 @@ public class AuthenticatedRegistrarAccessorTest {
 
   /** Succeed loading non-REAL registrar for admin. */
   @Test
-  public void testGetRegistrarForUser_notInContacts_isAdmin_notReal() throws Exception {
+  void testGetRegistrarForUser_notInContacts_isAdmin_notReal() throws Exception {
     expectGetRegistrarSuccess(
         OTE_CLIENT_ID_WITHOUT_CONTACT,
         GAE_ADMIN,
@@ -347,7 +347,7 @@ public class AuthenticatedRegistrarAccessorTest {
 
   /** Fail loading registrar even if admin, if registrar doesn't exist. */
   @Test
-  public void testGetRegistrarForUser_doesntExist_isAdmin() {
+  void testGetRegistrarForUser_doesntExist_isAdmin() {
     expectGetRegistrarFailure(
         "BadClientId",
         GAE_ADMIN,
@@ -382,7 +382,7 @@ public class AuthenticatedRegistrarAccessorTest {
 
   /** guessClientIdForUser returns the first clientId in getAllClientIdWithRoles. */
   @Test
-  public void testGuessClientIdForUser_hasAccess_returnsFirst() throws Exception {
+  void testGuessClientIdForUser_hasAccess_returnsFirst() throws Exception {
     AuthenticatedRegistrarAccessor registrarAccessor =
         AuthenticatedRegistrarAccessor.createForTesting(
             ImmutableSetMultimap.of(
@@ -395,7 +395,7 @@ public class AuthenticatedRegistrarAccessorTest {
 
   /** If a user doesn't have access to any registrars, guess fails. */
   @Test
-  public void testGuessClientIdForUser_noAccess_fails() {
+  void testGuessClientIdForUser_noAccess_fails() {
     AuthenticatedRegistrarAccessor registrarAccessor =
         AuthenticatedRegistrarAccessor.createForTesting(ImmutableSetMultimap.of());
 
@@ -405,7 +405,7 @@ public class AuthenticatedRegistrarAccessorTest {
   }
 
   @Test
-  public void testNullness() {
+  void testNullness() {
     new NullPointerTester()
         .setDefault(HttpServletRequest.class, req)
         .setDefault(HttpServletResponse.class, rsp)

core/src/test/java/google/registry/request/auth/LegacyAuthenticationMechanismTest.java

@@ -28,23 +28,22 @@ import google.registry.security.XsrfTokenManager;
 import google.registry.testing.AppEngineRule;
 import google.registry.testing.FakeClock;
 import javax.servlet.http.HttpServletRequest;
-import org.junit.After;
-import org.junit.Before;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.junit.jupiter.api.extension.RegisterExtension;
 import org.mockito.Mock;
-import org.mockito.junit.MockitoJUnit;
-import org.mockito.junit.MockitoRule;
+import org.mockito.junit.jupiter.MockitoExtension;
+import org.mockito.junit.jupiter.MockitoSettings;
+import org.mockito.quality.Strictness;
 
-@RunWith(JUnit4.class)
-public final class LegacyAuthenticationMechanismTest {
+/** Unit tests for {@link LegacyAuthenticationMechanism}. */
+@ExtendWith(MockitoExtension.class)
+final class LegacyAuthenticationMechanismTest {
 
-  @Rule
-  public final AppEngineRule appEngine = AppEngineRule.builder().withDatastoreAndCloudSql().build();
-
-  @Rule public final MockitoRule mocks = MockitoJUnit.rule();
+  @RegisterExtension
+  final AppEngineRule appEngine = AppEngineRule.builder().withDatastoreAndCloudSql().build();
 
   @Mock private UserService userService;
   @Mock private HttpServletRequest req;
@@ -54,8 +53,8 @@ public final class LegacyAuthenticationMechanismTest {
   private LegacyAuthenticationMechanism legacyAuthenticationMechanism;
   private String goodToken;
 
-  @Before
-  public void setUp() {
+  @BeforeEach
+  void beforeEach() {
     xsrfTokenManager = new XsrfTokenManager(clock, userService);
     legacyAuthenticationMechanism =
         new LegacyAuthenticationMechanism(userService, xsrfTokenManager);
@@ -64,8 +63,8 @@ public final class LegacyAuthenticationMechanismTest {
     goodToken = xsrfTokenManager.generateToken("email@example.com");
   }
 
-  @After
-  public void tearDown() {
+  @AfterEach
+  void afterEach() {
     // Make sure we didn't use getParameter or getInputStream or any of the other "with side
     // effects" getters unexpectedly. But allow "no side effect" getters.
     //
@@ -83,14 +82,15 @@ public final class LegacyAuthenticationMechanismTest {
   }
 
   @Test
-  public void testAuthenticate_notLoggedIn() {
+  @MockitoSettings(strictness = Strictness.LENIENT)
+  void testAuthenticate_notLoggedIn() {
     when(userService.isUserLoggedIn()).thenReturn(false);
     assertThat(legacyAuthenticationMechanism.authenticate(req).authLevel())
         .isEqualTo(AuthLevel.NONE);
   }
 
   @Test
-  public void testAuthenticate_loggedInSafeMethod_get() {
+  void testAuthenticate_loggedInSafeMethod_get() {
     when(userService.isUserLoggedIn()).thenReturn(true);
     when(req.getMethod()).thenReturn("GET");
     assertThat(legacyAuthenticationMechanism.authenticate(req).authLevel())
@@ -98,7 +98,7 @@ public final class LegacyAuthenticationMechanismTest {
   }
 
   @Test
-  public void testAuthenticate_loggedInSafeMethod_head() {
+  void testAuthenticate_loggedInSafeMethod_head() {
     when(userService.isUserLoggedIn()).thenReturn(true);
     when(req.getMethod()).thenReturn("HEAD");
     assertThat(legacyAuthenticationMechanism.authenticate(req).authLevel())
@@ -106,7 +106,8 @@ public final class LegacyAuthenticationMechanismTest {
   }
 
   @Test
-  public void testAuthenticate_loggedInUnsafeMethod_post_noXsrfToken() {
+  @MockitoSettings(strictness = Strictness.LENIENT)
+  void testAuthenticate_loggedInUnsafeMethod_post_noXsrfToken() {
     when(userService.isUserLoggedIn()).thenReturn(true);
     when(req.getMethod()).thenReturn("POST");
     assertThat(legacyAuthenticationMechanism.authenticate(req).authLevel())
@@ -118,7 +119,7 @@ public final class LegacyAuthenticationMechanismTest {
   }
 
   @Test
-  public void testAuthenticate_loggedInUnsafeMethod_post_goodTokenInHeader() {
+  void testAuthenticate_loggedInUnsafeMethod_post_goodTokenInHeader() {
     when(userService.isUserLoggedIn()).thenReturn(true);
     when(req.getMethod()).thenReturn("POST");
     when(req.getHeader("X-CSRF-Token")).thenReturn(goodToken);
@@ -131,7 +132,8 @@ public final class LegacyAuthenticationMechanismTest {
   }
 
   @Test
-  public void testAuthenticate_loggedInUnsafeMethod_post_badTokenInHeader() {
+  @MockitoSettings(strictness = Strictness.LENIENT)
+  void testAuthenticate_loggedInUnsafeMethod_post_badTokenInHeader() {
     when(userService.isUserLoggedIn()).thenReturn(true);
     when(req.getMethod()).thenReturn("POST");
     when(req.getHeader("X-CSRF-Token")).thenReturn("bad");
@@ -144,7 +146,7 @@ public final class LegacyAuthenticationMechanismTest {
   }
 
   @Test
-  public void testAuthenticate_loggedInUnsafeMethod_post_goodTokenInParam() {
+  void testAuthenticate_loggedInUnsafeMethod_post_goodTokenInParam() {
     when(userService.isUserLoggedIn()).thenReturn(true);
     when(req.getMethod()).thenReturn("POST");
     when(req.getParameter("xsrfToken")).thenReturn(goodToken);
@@ -157,7 +159,8 @@ public final class LegacyAuthenticationMechanismTest {
   }
 
   @Test
-  public void testAuthenticate_loggedInUnsafeMethod_post_badTokenInParam() {
+  @MockitoSettings(strictness = Strictness.LENIENT)
+  void testAuthenticate_loggedInUnsafeMethod_post_badTokenInParam() {
     when(userService.isUserLoggedIn()).thenReturn(true);
     when(req.getMethod()).thenReturn("POST");
     when(req.getParameter("xsrfToken")).thenReturn("bad");

core/src/test/java/google/registry/request/auth/RequestAuthenticatorTest.java

@@ -36,18 +36,15 @@ import google.registry.testing.FakeOAuthService;
 import google.registry.testing.FakeUserService;
 import java.util.Optional;
 import javax.servlet.http.HttpServletRequest;
-import org.junit.Before;
-import org.junit.Rule;
-import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.RegisterExtension;
 
 /** Unit tests for {@link RequestAuthenticator}. */
-@RunWith(JUnit4.class)
-public class RequestAuthenticatorTest {
+class RequestAuthenticatorTest {
+
+  @RegisterExtension final AppEngineRule appEngine = AppEngineRule.builder().build();
 
-  @Rule
-  public final AppEngineRule appEngine = AppEngineRule.builder().build();
   private static final AuthSettings AUTH_NONE = AuthSettings.create(
       ImmutableList.of(AuthMethod.INTERNAL),
       AuthLevel.NONE,
@@ -112,8 +109,8 @@ public class RequestAuthenticatorTest {
       "test-client-id",
       ImmutableList.of("test-scope1", "test-scope2", "nontest-scope"));
 
-  @Before
-  public void before() {
+  @BeforeEach
+  void beforeEach() {
     when(req.getMethod()).thenReturn("POST");
   }
 
@@ -135,7 +132,7 @@ public class RequestAuthenticatorTest {
   }
 
   @Test
-  public void testNoAuthNeeded_noneFound() {
+  void testNoAuthNeeded_noneFound() {
     Optional<AuthResult> authResult = runTest(mockUserService, AUTH_NONE);
 
     verifyNoInteractions(mockUserService);
@@ -144,7 +141,7 @@ public class RequestAuthenticatorTest {
   }
 
   @Test
-  public void testNoAuthNeeded_internalFound() {
+  void testNoAuthNeeded_internalFound() {
     when(req.getHeader("X-AppEngine-QueueName")).thenReturn("__cron");
 
     Optional<AuthResult> authResult = runTest(mockUserService, AUTH_NONE);
@@ -156,7 +153,7 @@ public class RequestAuthenticatorTest {
   }
 
   @Test
-  public void testInternalAuth_notInvokedInternally() {
+  void testInternalAuth_notInvokedInternally() {
     Optional<AuthResult> authResult = runTest(mockUserService, AUTH_INTERNAL_OR_ADMIN);
 
     verifyNoInteractions(mockUserService);
@@ -164,7 +161,7 @@ public class RequestAuthenticatorTest {
   }
 
   @Test
-  public void testInternalAuth_success() {
+  void testInternalAuth_success() {
     when(req.getHeader("X-AppEngine-QueueName")).thenReturn("__cron");
 
     Optional<AuthResult> authResult = runTest(mockUserService, AUTH_INTERNAL_OR_ADMIN);
@@ -176,14 +173,14 @@ public class RequestAuthenticatorTest {
   }
 
   @Test
-  public void testAnyUserAnyMethod_notLoggedIn() {
+  void testAnyUserAnyMethod_notLoggedIn() {
     Optional<AuthResult> authResult = runTest(fakeUserService, AUTH_ANY_USER_ANY_METHOD);
 
     assertThat(authResult).isEmpty();
   }
 
   @Test
-  public void testAnyUserAnyMethod_xsrfFailure() {
+  void testAnyUserAnyMethod_xsrfFailure() {
     fakeUserService.setUser(testUser, false);
 
     Optional<AuthResult> authResult = runTest(fakeUserService, AUTH_ANY_USER_ANY_METHOD);
@@ -192,7 +189,7 @@ public class RequestAuthenticatorTest {
   }
 
   @Test
-  public void testAnyUserAnyMethod_success() {
+  void testAnyUserAnyMethod_success() {
     fakeUserService.setUser(testUser, false /* isAdmin */);
     when(req.getHeader(XsrfTokenManager.X_CSRF_TOKEN))
         .thenReturn(xsrfTokenManager.generateToken(testUser.getEmail()));
@@ -208,7 +205,7 @@ public class RequestAuthenticatorTest {
   }
 
   @Test
-  public void testAnyUserAnyMethod_xsrfNotRequiredForGet() {
+  void testAnyUserAnyMethod_xsrfNotRequiredForGet() {
     fakeUserService.setUser(testUser, false);
     when(req.getMethod()).thenReturn("GET");
 
@@ -222,14 +219,14 @@ public class RequestAuthenticatorTest {
   }
 
   @Test
-  public void testAdminUserAnyMethod_notLoggedIn() {
+  void testAdminUserAnyMethod_notLoggedIn() {
     Optional<AuthResult> authResult = runTest(fakeUserService, AUTH_ADMIN_USER_ANY_METHOD);
 
     assertThat(authResult).isEmpty();
   }
 
   @Test
-  public void testAdminUserAnyMethod_notAdminUser() {
+  void testAdminUserAnyMethod_notAdminUser() {
     fakeUserService.setUser(testUser, false /* isAdmin */);
 
     Optional<AuthResult> authResult = runTest(fakeUserService, AUTH_ADMIN_USER_ANY_METHOD);
@@ -238,7 +235,7 @@ public class RequestAuthenticatorTest {
   }
 
   @Test
-  public void testAdminUserAnyMethod_xsrfFailure() {
+  void testAdminUserAnyMethod_xsrfFailure() {
     fakeUserService.setUser(testUser, true);
 
     Optional<AuthResult> authResult = runTest(fakeUserService, AUTH_ADMIN_USER_ANY_METHOD);
@@ -247,7 +244,7 @@ public class RequestAuthenticatorTest {
   }
 
   @Test
-  public void testAdminUserAnyMethod_success() {
+  void testAdminUserAnyMethod_success() {
     fakeUserService.setUser(testUser, true /* isAdmin */);
     when(req.getHeader(XsrfTokenManager.X_CSRF_TOKEN))
         .thenReturn(xsrfTokenManager.generateToken(testUser.getEmail()));
@@ -263,7 +260,7 @@ public class RequestAuthenticatorTest {
   }
 
   @Test
-  public void testOAuth_success() {
+  void testOAuth_success() {
     fakeOAuthService.setUser(testUser);
     fakeOAuthService.setOAuthEnabled(true);
     when(req.getHeader(AUTHORIZATION)).thenReturn("Bearer TOKEN");
@@ -285,7 +282,7 @@ public class RequestAuthenticatorTest {
   }
 
   @Test
-  public void testOAuthAdmin_success() {
+  void testOAuthAdmin_success() {
     fakeOAuthService.setUser(testUser);
     fakeOAuthService.setUserAdmin(true);
     fakeOAuthService.setOAuthEnabled(true);
@@ -308,7 +305,7 @@ public class RequestAuthenticatorTest {
   }
 
   @Test
-  public void testOAuthMissingAuthenticationToken_failure() {
+  void testOAuthMissingAuthenticationToken_failure() {
     fakeOAuthService.setUser(testUser);
     fakeOAuthService.setOAuthEnabled(true);
 
@@ -318,7 +315,7 @@ public class RequestAuthenticatorTest {
   }
 
   @Test
-  public void testOAuthClientIdMismatch_failure() {
+  void testOAuthClientIdMismatch_failure() {
     fakeOAuthService.setUser(testUser);
     fakeOAuthService.setOAuthEnabled(true);
     fakeOAuthService.setClientId("wrong-client-id");
@@ -330,7 +327,7 @@ public class RequestAuthenticatorTest {
   }
 
   @Test
-  public void testOAuthNoScopes_failure() {
+  void testOAuthNoScopes_failure() {
     fakeOAuthService.setUser(testUser);
     fakeOAuthService.setOAuthEnabled(true);
     fakeOAuthService.setAuthorizedScopes();
@@ -342,7 +339,7 @@ public class RequestAuthenticatorTest {
   }
 
   @Test
-  public void testOAuthMissingScope_failure() {
+  void testOAuthMissingScope_failure() {
     fakeOAuthService.setUser(testUser);
     fakeOAuthService.setOAuthEnabled(true);
     fakeOAuthService.setAuthorizedScopes("test-scope1", "test-scope3");
@@ -354,7 +351,7 @@ public class RequestAuthenticatorTest {
   }
 
   @Test
-  public void testOAuthExtraScope_success() {
+  void testOAuthExtraScope_success() {
     fakeOAuthService.setUser(testUser);
     fakeOAuthService.setOAuthEnabled(true);
     fakeOAuthService.setAuthorizedScopes("test-scope1", "test-scope2", "test-scope3");
@@ -377,7 +374,7 @@ public class RequestAuthenticatorTest {
   }
 
   @Test
-  public void testAnyUserNoLegacy_failureWithLegacyUser() {
+  void testAnyUserNoLegacy_failureWithLegacyUser() {
     fakeUserService.setUser(testUser, false /* isAdmin */);
 
     Optional<AuthResult> authResult = runTest(fakeUserService, AUTH_ANY_USER_NO_LEGACY);
@@ -386,7 +383,7 @@ public class RequestAuthenticatorTest {
   }
 
   @Test
-  public void testCheckAuthConfig_NoMethods_failure() {
+  void testCheckAuthConfig_NoMethods_failure() {
     IllegalArgumentException thrown =
         assertThrows(
             IllegalArgumentException.class,
@@ -395,7 +392,7 @@ public class RequestAuthenticatorTest {
   }
 
   @Test
-  public void testCheckAuthConfig_WrongMethodOrdering_failure() {
+  void testCheckAuthConfig_WrongMethodOrdering_failure() {
     IllegalArgumentException thrown =
         assertThrows(
             IllegalArgumentException.class,
@@ -406,7 +403,7 @@ public class RequestAuthenticatorTest {
   }
 
   @Test
-  public void testCheckAuthConfig_DuplicateMethods_failure() {
+  void testCheckAuthConfig_DuplicateMethods_failure() {
     IllegalArgumentException thrown =
         assertThrows(
             IllegalArgumentException.class,
@@ -417,7 +414,7 @@ public class RequestAuthenticatorTest {
   }
 
   @Test
-  public void testCheckAuthConfig_InternalWithUser_failure() {
+  void testCheckAuthConfig_InternalWithUser_failure() {
     IllegalArgumentException thrown =
         assertThrows(
             IllegalArgumentException.class,
@@ -428,7 +425,7 @@ public class RequestAuthenticatorTest {
   }
 
   @Test
-  public void testCheckAuthConfig_WronglyIgnoringUser_failure() {
+  void testCheckAuthConfig_WronglyIgnoringUser_failure() {
     IllegalArgumentException thrown =
         assertThrows(
             IllegalArgumentException.class,

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

@@ -60,11 +60,10 @@ import org.mockito.Mock;
 import org.mockito.junit.jupiter.MockitoExtension;
 
 @ExtendWith(MockitoExtension.class)
-public final class ConsoleRegistrarCreatorActionTest {
+final class ConsoleRegistrarCreatorActionTest {
 
   @RegisterExtension
-  public final AppEngineRule appEngineRule =
-      AppEngineRule.builder().withDatastoreAndCloudSql().build();
+  final AppEngineRule appEngineRule = AppEngineRule.builder().withDatastoreAndCloudSql().build();
 
   @RegisterExtension
   @Order(value = Integer.MAX_VALUE)