API Tools Test: find out why sealed GC fails.

apitools/org.eclipse.pde.api.tools.tests/src/org/eclipse/pde/api/tools/comparator/tests/ClassDeltaSealedTests.java

@@ -0,0 +1,108 @@
+/*******************************************************************************
+ * Copyright (c) 2025 SAP SE and others.
+ *
+ * This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License 2.0
+ * which accompanies this distribution, and is available at
+ * https://www.eclipse.org/legal/epl-2.0/
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ *     SAP SE - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.pde.api.tools.comparator.tests;
+
+import static org.assertj.core.api.Assertions.fail;
+import static org.junit.Assert.assertNotNull;
+
+import org.eclipse.pde.api.tools.internal.provisional.VisibilityModifiers;
+import org.eclipse.pde.api.tools.internal.provisional.comparator.ApiComparator;
+import org.eclipse.pde.api.tools.internal.provisional.comparator.IDelta;
+import org.eclipse.pde.api.tools.internal.provisional.model.IApiBaseline;
+import org.eclipse.pde.api.tools.internal.provisional.model.IApiComponent;
+import org.junit.Test;
+
+/**
+ * Observes what deltas the API comparator produces for three scenarios,
+ * all starting from a baseline with a {@code final} GC class with a
+ * {@code @noreference} handle field:
+ *
+ * <ul>
+ *   <li>test100: final GC + handle → final GC + handle (no modifier change)</li>
+ *   <li>test101: final GC + handle → sealed GC + handle + GCExtension</li>
+ *   <li>test102: final GC + handle → normal GC + handle + GCExtension</li>
+ * </ul>
+ *
+ * All tests compile with Java 17.
+ * The tests never fail — they print the resulting deltas to System.out.
+ */
+public class ClassDeltaSealedTests extends DeltaTestSetup {
+
+	@Override
+	public String getTestRoot() {
+		return "class"; //$NON-NLS-1$
+	}
+
+	@Override
+	protected String[] getCompilerOptions() {
+		return new String[] { "-17", "-preserveAllLocals", "-nowarn" }; //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
+	}
+
+	/**
+	 * Scenario 1: final GC + handle → final GC + handle (no modifier change).
+	 */
+	@Test
+	public void test100() {
+		observeDeltas("test100"); //$NON-NLS-1$
+		fail("show"); //$NON-NLS-1$
+	}
+
+	/**
+	 * Scenario 2: final GC + handle → sealed GC + handle + GCExtension.
+	 */
+	@Test
+	public void test101() {
+		observeDeltas("test101"); //$NON-NLS-1$
+		fail("show"); //$NON-NLS-1$
+	}
+
+	/**
+	 * Scenario 3: final GC + handle → normal GC + handle + GCExtension.
+	 */
+	@Test
+	public void test102() {
+		observeDeltas("test102"); //$NON-NLS-1$
+		fail("show"); //$NON-NLS-1$
+
+	}
+
+	private void observeDeltas(String testName) {
+		deployBundles(testName);
+		IApiBaseline before = getBeforeState();
+		IApiBaseline after = getAfterState();
+		IApiComponent beforeComp = before.getApiComponent(BUNDLE_NAME);
+		assertNotNull("no before api component", beforeComp); //$NON-NLS-1$
+		IApiComponent afterComp = after.getApiComponent(BUNDLE_NAME);
+		assertNotNull("no after api component", afterComp); //$NON-NLS-1$
+
+		IDelta delta = ApiComparator.compare(beforeComp, afterComp, before, after,
+				VisibilityModifiers.ALL_VISIBILITIES, null);
+		assertNotNull("No delta", delta); //$NON-NLS-1$
+
+		System.out.println("=== Deltas for " + testName + " ==="); //$NON-NLS-1$ //$NON-NLS-2$
+		if (delta == ApiComparator.NO_DELTA) {
+			System.out.println("  NO_DELTA"); //$NON-NLS-1$
+			return;
+		}
+		IDelta[] leaves = collectLeaves(delta);
+		System.out.println("  count=" + leaves.length); //$NON-NLS-1$
+		for (IDelta leaf : leaves) {
+			System.out.println("  kind=" + leaf.getKind() //$NON-NLS-1$
+					+ " flags=" + leaf.getFlags() //$NON-NLS-1$
+					+ " elementType=" + leaf.getElementType() //$NON-NLS-1$
+					+ " key=" + leaf.getKey() //$NON-NLS-1$
+					+ " msg=" + leaf.getMessage()); //$NON-NLS-1$
+		}
+	}
+}

apitools/org.eclipse.pde.api.tools.tests/src/org/eclipse/pde/api/tools/comparator/tests/DeltaTestSetup.java

@@ -166,13 +166,21 @@ protected void deployBundle(String testName, String name, String bundleName) {
 				TestSuiteHelper.getPluginDirectoryPath().append(TESTS_DELTAS_NAME).append(getTestRoot()).append(testName).append(name).toOSString()
 		};
 		IPath destinationPath = WORKSPACE_ROOT.append(name).append(bundleName);
-		String[] compilerOptions = TestSuiteHelper.getCompilerOptions();
+		String[] compilerOptions = getCompilerOptions();
 		assertTrue(TestSuiteHelper.compile(sourceFilePaths, destinationPath.toOSString(), compilerOptions));
 
 		// copy the MANIFEST in the workspace folder
 		copyResources(testName, name, destinationPath.toOSString());
 	}
 
+	/**
+	 * Returns the compiler options to use when compiling test bundles.
+	 * Subclasses may override to use a different Java compliance level.
+	 */
+	protected String[] getCompilerOptions() {
+		return TestSuiteHelper.getCompilerOptions();
+	}
+
 	protected void deployBundles(String testName) {
 		deployBundle(testName, BEFORE);
 		deployBundle(testName, AFTER);

apitools/org.eclipse.pde.api.tools.tests/tests-deltas/class/test100/after/GC.java

@@ -0,0 +1,8 @@
+public final class GC {
+
+	/**
+	 * @noreference This field is not intended to be referenced by clients.
+	 */
+	public long handle;
+
+}

apitools/org.eclipse.pde.api.tools.tests/tests-deltas/class/test100/before/GC.java

@@ -0,0 +1,8 @@
+public final class GC {
+
+	/**
+	 * @noreference This field is not intended to be referenced by clients.
+	 */
+	public long handle;
+
+}

apitools/org.eclipse.pde.api.tools.tests/tests-deltas/class/test100/resources/META-INF/MANIFEST.MF

@@ -0,0 +1,8 @@
+Manifest-Version: 1.0
+Bundle-ManifestVersion: 2
+Bundle-Name: deltatest Plug-in
+Bundle-SymbolicName: deltatest
+Bundle-Version: 1.0.0
+Bundle-RequiredExecutionEnvironment: JavaSE-17
+Export-Package: .,
+ p

apitools/org.eclipse.pde.api.tools.tests/tests-deltas/class/test101/after/GC.java

@@ -0,0 +1,8 @@
+public sealed class GC permits GCExtension {
+
+	/**
+	 * @noreference This field is not intended to be referenced by clients.
+	 */
+	public long handle;
+
+}

apitools/org.eclipse.pde.api.tools.tests/tests-deltas/class/test101/after/GCExtension.java

@@ -0,0 +1,3 @@
+public final class GCExtension extends GC {
+
+}

apitools/org.eclipse.pde.api.tools.tests/tests-deltas/class/test101/before/GC.java

@@ -0,0 +1,8 @@
+public final class GC {
+
+	/**
+	 * @noreference This field is not intended to be referenced by clients.
+	 */
+	public long handle;
+
+}

apitools/org.eclipse.pde.api.tools.tests/tests-deltas/class/test101/resources/META-INF/MANIFEST.MF

@@ -0,0 +1,8 @@
+Manifest-Version: 1.0
+Bundle-ManifestVersion: 2
+Bundle-Name: deltatest Plug-in
+Bundle-SymbolicName: deltatest
+Bundle-Version: 1.0.0
+Bundle-RequiredExecutionEnvironment: JavaSE-17
+Export-Package: .,
+ p

apitools/org.eclipse.pde.api.tools.tests/tests-deltas/class/test101/resources/after/META-INF/MANIFEST.MF

@@ -6,5 +6,5 @@ Bundle-Name: deltatest Plug-in
 Bundle-SymbolicName: deltatest
 Bundle-Version: 1.0.0
 Bundle-RequiredExecutionEnvironment: J2SE-1.4
-Export-Package: p
-
+Export-Package: .,
+ p

apitools/org.eclipse.pde.api.tools.tests/tests-deltas/class/test102/after/GC.java

@@ -0,0 +1,8 @@
+public class GC {
+
+	/**
+	 * @noreference This field is not intended to be referenced by clients.
+	 */
+	public long handle;
+
+}

apitools/org.eclipse.pde.api.tools.tests/tests-deltas/class/test102/after/GCExtension.java

@@ -0,0 +1,3 @@
+public class GCExtension extends GC {
+
+}

apitools/org.eclipse.pde.api.tools.tests/tests-deltas/class/test102/before/GC.java

@@ -0,0 +1,8 @@
+public final class GC {
+
+	/**
+	 * @noreference This field is not intended to be referenced by clients.
+	 */
+	public long handle;
+
+}

apitools/org.eclipse.pde.api.tools.tests/tests-deltas/class/test102/resources/META-INF/MANIFEST.MF

@@ -0,0 +1,8 @@
+Manifest-Version: 1.0
+Bundle-ManifestVersion: 2
+Bundle-Name: deltatest Plug-in
+Bundle-SymbolicName: deltatest
+Bundle-Version: 1.0.0
+Bundle-RequiredExecutionEnvironment: JavaSE-17
+Export-Package: .,
+ p