How to use junit.jupiter Extensions in OSGi and plain java

Author: jukzi

eclipse.platform.releng/bundles/org.eclipse.test/META-INF/MANIFEST.MF

@@ -11,7 +11,9 @@ Require-Bundle: org.apache.ant,
  org.eclipse.core.runtime,
  org.eclipse.ui.ide.application,
  org.eclipse.equinox.app,
- org.junit
+ org.apache.aries.spifly.dynamic.bundle,
+ org.junit,
+ junit-jupiter-api
 Import-Package: org.junit.jupiter.api,
  org.junit.platform.engine,
  org.junit.platform.engine.discovery,
@@ -24,5 +26,6 @@ Import-Package: org.junit.jupiter.api,
  org.junit.jupiter.engine
 Bundle-ActivationPolicy: lazy
 Bundle-RequiredExecutionEnvironment: JavaSE-17
-Export-Package: org.eclipse.test
+Export-Package: org.eclipse.test,
+ org.eclipse.test.services
 Automatic-Module-Name: org.eclipse.test

eclipse.platform.releng/bundles/org.eclipse.test/src/META-INF/services/org.junit.jupiter.api.extension.Extension

@@ -0,0 +1 @@
+org.eclipse.test.services.LoggingTestExtension

eclipse.platform.releng/bundles/org.eclipse.test/src/junit-platform.properties

@@ -0,0 +1 @@
+junit.jupiter.extensions.autodetection.enabled=true

eclipse.platform.releng/bundles/org.eclipse.test/src/org/eclipse/test/services/LoggingTestExtension.java

@@ -0,0 +1,43 @@
+package org.eclipse.test.services;
+
+import org.junit.jupiter.api.extension.AfterTestExecutionCallback;
+import org.junit.jupiter.api.extension.BeforeTestExecutionCallback;
+import org.junit.jupiter.api.extension.ExtensionContext;
+import org.junit.jupiter.api.extension.ExtensionContext.Namespace;
+import org.junit.jupiter.api.extension.ExtensionContext.Store;
+
+/** logs start, stop, duration, error for all tests executed **/
+public class LoggingTestExtension implements AfterTestExecutionCallback, BeforeTestExecutionCallback {
+	public static String BEFORE_TEST_START = "Test Before: ";
+	public static String AFTER_TEST_PASSED = "Test Passed: ";
+	public static String AFTER_TEST_FAILED = "Test Failed: ";
+
+	public LoggingTestExtension() {
+		System.out.println("LoggingTestService");
+	}
+	@Override
+	public void beforeTestExecution(ExtensionContext context) throws Exception {
+		long n0 = System.nanoTime();
+		getStore(context).put("TIME", n0);
+		System.out.println(BEFORE_TEST_START + context.getDisplayName());
+	}
+
+	@Override
+	public void afterTestExecution(ExtensionContext context) throws Exception {
+		long t1 = System.nanoTime();
+		long t0 = getStore(context).remove("TIME", long.class);
+		String took = " after: " + (t1 - t0) / 1_000_000 + "ms";
+		Throwable t = context.getExecutionException().orElse(null);
+		if (t == null) {
+			System.out.println(AFTER_TEST_PASSED + context.getDisplayName() + took);
+		} else {
+			System.out.println(AFTER_TEST_FAILED + context.getDisplayName() + took);
+			t.printStackTrace(System.out);
+		}
+	}
+
+	private Store getStore(ExtensionContext context) {
+		return context.getStore(Namespace.create(getClass(), context.getRequiredTestMethod()));
+	}
+
+}

eclipse.platform.releng/bundles/org.eclipse.test/src/org/eclipse/test/services/LoggingTestExtensionTest.java

@@ -0,0 +1,37 @@
+package org.eclipse.test.services;
+
+import static org.junit.Assert.assertTrue;
+
+import java.io.ByteArrayOutputStream;
+import java.io.PrintStream;
+
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.api.BeforeAll;
+import org.junit.jupiter.api.Test;
+
+/** verifies the Extension is used **/
+public class LoggingTestExtensionTest {
+	private static final String SOMETHING = "something";
+	private static final ByteArrayOutputStream OUT = new ByteArrayOutputStream();
+	private static PrintStream oldStdOut;
+
+	@BeforeAll
+	public static void beforeAll() {
+		oldStdOut = System.out;
+		System.setOut(new PrintStream(OUT));
+	}
+	@Test
+	public void testWritten() {
+		System.out.println(SOMETHING);
+	}
+
+	@AfterAll
+	public static void afterAll() {
+		String output = new String(OUT.toByteArray());
+		System.setOut(oldStdOut);
+		assertTrue(output, output.contains("testWritten"));
+		assertTrue(output, output.contains(SOMETHING));
+		assertTrue(output, output.contains(org.eclipse.test.services.LoggingTestExtension.BEFORE_TEST_START));
+		assertTrue(output, output.contains(org.eclipse.test.services.LoggingTestExtension.AFTER_TEST_PASSED));
+	}
+}

eclipse.platform.releng/bundles/org.eclipse.test/src/org/eclipse/test/services/LoggingTestExtensionTest2.java

@@ -0,0 +1,18 @@
+package org.eclipse.test.services;
+
+import org.junit.jupiter.api.Test;
+
+// Manual demonstration:
+public class LoggingTestExtensionTest2 {
+
+	@Test
+	public void testWritten() {
+		System.out.println("real");
+	}
+
+	@Test
+	public void testWritten2() {
+		throw new RuntimeException("intended");
+	}
+
+}