Add integration test

Issue: #2229
Signed-off-by: yongjunhong <kevin0928@naver.com>

junit-vintage-engine/src/test/java/org/junit/vintage/engine/execution/ParallelExecutionIntegrationTests.java

@@ -0,0 +1,107 @@
+/*
+ * Copyright 2015-2024 the original author or authors.
+ *
+ * All rights reserved. This program and the accompanying materials are
+ * made available under the terms of the Eclipse Public License v2.0 which
+ * accompanies this distribution and is available at
+ *
+ * https://www.eclipse.org/legal/epl-v20.html
+ */
+
+package org.junit.vintage.engine.execution;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.junit.platform.testkit.engine.EventConditions.event;
+import static org.junit.platform.testkit.engine.EventConditions.finishedSuccessfully;
+import static org.junit.platform.testkit.engine.EventConditions.finishedWithFailure;
+import static org.junit.platform.testkit.engine.EventConditions.started;
+import static org.junit.platform.testkit.engine.EventConditions.test;
+import static org.junit.vintage.engine.samples.junit4.JUnit4ParallelTestCase.*;
+
+import java.time.Instant;
+import java.util.Arrays;
+import java.util.List;
+
+import org.assertj.core.api.Condition;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.TestReporter;
+import org.junit.platform.engine.discovery.ClassSelector;
+import org.junit.platform.engine.discovery.DiscoverySelectors;
+import org.junit.platform.launcher.LauncherDiscoveryRequest;
+import org.junit.platform.launcher.core.LauncherDiscoveryRequestBuilder;
+import org.junit.platform.testkit.engine.EngineExecutionResults;
+import org.junit.platform.testkit.engine.EngineTestKit;
+import org.junit.platform.testkit.engine.Event;
+import org.junit.platform.testkit.engine.Events;
+import org.junit.vintage.engine.VintageTestEngine;
+
+class ParallelExecutionIntegrationTests {
+
+	private static final String PARALLEL_EXECUTION_ENABLED = "junit.vintage.execution.parallel.enabled";
+	private static final String PARALLEL_POOL_SIZE = "junit.vintage.execution.parallel.pool-size";
+
+	@Test
+	void successfulParallelTest(TestReporter reporter) {
+		var events = executeInParallelSuccessfully(3, SuccessfulParallelTestCase.class).list();
+
+		var startedTimestamps = getTimestampsFor(events, event(test(), started()));
+		var finishedTimestamps = getTimestampsFor(events, event(test(), finishedSuccessfully()));
+
+		reporter.publishEntry("startedTimestamps", startedTimestamps.toString());
+		reporter.publishEntry("finishedTimestamps", finishedTimestamps.toString());
+
+		assertThat(startedTimestamps).hasSize(3);
+		assertThat(finishedTimestamps).hasSize(3);
+	}
+
+	@Test
+	void failingParallelTest(TestReporter reporter) {
+		var events = executeInParallel(3, FailingParallelTestCase.class).list();
+
+		var startedTimestamps = getTimestampsFor(events, event(test(), started()));
+		var finishedTimestamps = getTimestampsFor(events, event(test(), finishedWithFailure()));
+		reporter.publishEntry("startedTimestamps", startedTimestamps.toString());
+		reporter.publishEntry("finishedTimestamps", finishedTimestamps.toString());
+
+		assertThat(startedTimestamps).hasSize(3);
+		assertThat(finishedTimestamps).hasSize(3);
+	}
+
+	private List<Instant> getTimestampsFor(List<Event> events, Condition<Event> condition) {
+		// @formatter:off
+		return events.stream()
+				.filter(condition::matches)
+				.map(Event::getTimestamp)
+				.toList();
+		// @formatter:on
+	}
+
+	private Events executeInParallelSuccessfully(int poolSize, Class<?>... testClasses) {
+		var events = execute(poolSize, testClasses).allEvents();
+		try {
+			return events.assertStatistics(it -> it.failed(0));
+		}
+		catch (AssertionError error) {
+			events.debug();
+			throw error;
+		}
+	}
+
+	private Events executeInParallel(int poolSize, Class<?>... testClasses) {
+		return execute(poolSize, testClasses).allEvents();
+	}
+
+	private static EngineExecutionResults execute(int poolSize, Class<?>... testClass) {
+		return EngineTestKit.execute(new VintageTestEngine(), request(poolSize, testClass));
+	}
+
+	private static LauncherDiscoveryRequest request(int poolSize, Class<?>... testClasses) {
+		var classSelectors = Arrays.stream(testClasses) //
+				.map(DiscoverySelectors::selectClass) //
+				.toArray(ClassSelector[]::new);
+
+		return LauncherDiscoveryRequestBuilder.request().selectors(classSelectors).configurationParameter(PARALLEL_EXECUTION_ENABLED,
+			String.valueOf(true)).configurationParameter(PARALLEL_POOL_SIZE, String.valueOf(poolSize)).build();
+	}
+
+}

junit-vintage-engine/src/testFixtures/java/org/junit/vintage/engine/samples/junit4/JUnit4ParallelTestCase.java

@@ -0,0 +1,83 @@
+/*
+ * Copyright 2015-2024 the original author or authors.
+ *
+ * All rights reserved. This program and the accompanying materials are
+ * made available under the terms of the Eclipse Public License v2.0 which
+ * accompanies this distribution and is available at
+ *
+ * https://www.eclipse.org/legal/epl-v20.html
+ */
+
+package org.junit.vintage.engine.samples.junit4;
+
+import static java.util.concurrent.TimeUnit.MILLISECONDS;
+import static org.junit.Assert.*;
+
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.atomic.AtomicInteger;
+
+import org.junit.BeforeClass;
+import org.junit.Test;
+import org.junit.experimental.runners.Enclosed;
+import org.junit.runner.RunWith;
+
+@RunWith(Enclosed.class)
+public class JUnit4ParallelTestCase {
+
+	public static class SuccessfulParallelTestCase {
+		static AtomicInteger sharedResource;
+		static CountDownLatch countDownLatch;
+
+		@BeforeClass
+		public static void initialize() {
+			sharedResource = new AtomicInteger();
+			countDownLatch = new CountDownLatch(3);
+		}
+
+		@Test
+		public void firstTest() throws Exception {
+			incrementAndBlock(sharedResource, countDownLatch);
+		}
+
+		@Test
+		public void secondTest() throws Exception {
+			incrementAndBlock(sharedResource, countDownLatch);
+		}
+
+		@Test
+		public void thirdTest() throws Exception {
+			incrementAndBlock(sharedResource, countDownLatch);
+		}
+	}
+
+	public static class FailingParallelTestCase {
+		@Test
+		public void firstTest() {
+			fail("failing test");
+		}
+
+		@Test
+		public void secondTest() {
+			fail("failing test");
+		}
+
+		@Test
+		public void thirdTest() {
+			fail("failing test");
+		}
+	}
+
+	@SuppressWarnings("ResultOfMethodCallIgnored")
+	private static int incrementAndBlock(AtomicInteger sharedResource, CountDownLatch countDownLatch)
+			throws InterruptedException {
+		var value = sharedResource.incrementAndGet();
+		countDownLatch.countDown();
+		countDownLatch.await(estimateSimulatedTestDurationInMiliseconds(), MILLISECONDS);
+		return value;
+	}
+
+	private static long estimateSimulatedTestDurationInMiliseconds() {
+		var runningInCi = Boolean.parseBoolean(System.getenv("CI"));
+		return runningInCi ? 1000 : 100;
+	}
+}