Log resource deltas during FileBuffersForFilesInLinkedFolders

FileBuffersForFilesInLinkedFolders.test16_3() fails infrequently during CI jobs,
the fail indicates a missing resource delta notification.

This change adds logging for resource deltas during FileBuffersForFilesInLinkedFolders tests,
which should help detecting potential concurrent workspace operations.

In addition, an extra check in FileBufferFunctions.test16_3() is added,
validating that the test file buffer was not disconnected prematurely.

See: #2528

Author: trancexpress

tests/org.eclipse.core.filebuffers.tests/src/org/eclipse/core/filebuffers/tests/FileBufferFunctions.java

@@ -35,10 +35,19 @@
 import org.eclipse.core.filesystem.EFS;
 import org.eclipse.core.filesystem.IFileInfo;
 import org.eclipse.core.filesystem.IFileStore;
+import org.eclipse.core.internal.filebuffers.ResourceFileBuffer;
 
+import org.eclipse.core.runtime.CoreException;
+import org.eclipse.core.runtime.ILog;
 import org.eclipse.core.runtime.IPath;
+import org.eclipse.core.runtime.Status;
 
 import org.eclipse.core.resources.IProject;
+import org.eclipse.core.resources.IResourceChangeEvent;
+import org.eclipse.core.resources.IResourceChangeListener;
+import org.eclipse.core.resources.IResourceDelta;
+import org.eclipse.core.resources.IResourceDeltaVisitor;
+import org.eclipse.core.resources.ResourcesPlugin;
 
 import org.eclipse.core.filebuffers.FileBuffers;
 import org.eclipse.core.filebuffers.IFileBuffer;
@@ -55,6 +64,8 @@
  */
 public abstract class FileBufferFunctions {
 
+	private static final IResourceChangeListener LOG_RESOURCE_DELTAS_LISTENER= FileBufferFunctions::logDeltaEvent;
+
 	private IProject fProject;
 	protected ITextFileBufferManager fManager;
 	private IPath fPath;
@@ -82,6 +93,9 @@ public void setUp() throws Exception {
 		fPath= createPath(fProject);
 		ITextFileBuffer buffer= fManager.getTextFileBuffer(fPath, LocationKind.NORMALIZE);
 		assertNull(buffer);
+		if (logResourceDeltas()) {
+			ResourcesPlugin.getWorkspace().addResourceChangeListener(LOG_RESOURCE_DELTAS_LISTENER);
+		}
 	}
 
 	protected IProject getProject() {
@@ -90,6 +104,9 @@ protected IProject getProject() {
 
 	@AfterEach
 	public void tearDown() {
+		if (logResourceDeltas()) {
+			ResourcesPlugin.getWorkspace().removeResourceChangeListener(LOG_RESOURCE_DELTAS_LISTENER);
+		}
 		ITextFileBuffer buffer= fManager.getTextFileBuffer(fPath, LocationKind.NORMALIZE);
 		assertNull(buffer);
 		ResourceHelper.deleteProject("project");
@@ -99,6 +116,10 @@ protected IPath getPath() {
 		return fPath;
 	}
 
+	protected boolean logResourceDeltas() {
+		return false;
+	}
+
 	@RegisterExtension
 	public TestFailExtension failReporter= new TestFailExtension();
 
@@ -1004,6 +1025,9 @@ public void stateChanging(IFileBuffer buf) {
 
 				fileBuffer= fManager.getTextFileBuffer(fPath, LocationKind.NORMALIZE);
 				if (moveUnderlyingFile() != null) {
+					if (fileBuffer instanceof ResourceFileBuffer buffer) {
+						assertFalse(buffer.isDisconnected(), "Buffer should not be disconnected");
+					}
 					assertEquals(1, listener.count);
 					assertSame(fileBuffer, listener.buffer);
 				}
@@ -1294,4 +1318,33 @@ public void testGetFileBuffers() throws Exception {
 		}
 	}
 
+	protected static void logDeltaEvent(IResourceChangeEvent event) {
+		ILog log= FileBuffersTestPlugin.getDefault().getLog();
+		StringBuilder s= new StringBuilder();
+		s.append("[");
+		s.append(Thread.currentThread().getName());
+		s.append("] thread logging resource change event");
+		s.append(System.lineSeparator());
+		s.append("Delta:");
+		IResourceDelta delta= event.getDelta();
+		if (delta != null) {
+			IResourceDeltaVisitor visitor= new IResourceDeltaVisitor() {
+				@Override
+				public boolean visit(IResourceDelta d) throws CoreException {
+					s.append(System.lineSeparator());
+					s.append("\tkind: ");
+					s.append(d.getKind());
+					s.append(", resource: ");
+					s.append(d.getResource());
+					return true;
+				}
+			};
+			try {
+				delta.accept(visitor);
+			} catch (CoreException e) {
+				log.log(Status.error("Error occurred while visiting delta", e));
+			}
+		}
+		log.log(Status.info(s.toString()));
+	}
 }

tests/org.eclipse.core.filebuffers.tests/src/org/eclipse/core/filebuffers/tests/FileBuffersForFilesInLinkedFolders.java

@@ -126,4 +126,9 @@ protected Class<IAnnotationModel> getAnnotationModelClass() throws Exception {
 		Bundle bundle= Platform.getBundle("org.eclipse.ui.editors");
 		return bundle != null ? IAnnotationModel.class : null;
 	}
+
+	@Override
+	protected boolean logResourceDeltas() {
+		return true;
+	}
 }