Bug 500061 - Compare editor does not link with Project ExplorerI20190114-1800

Add an ILinkHelper to link the EditorInput of a CompareEditor to the
CommonNavigator.
- The LinkHelper links the IFile of the active sub-editor to the
CommonNavigator, when the CompareEditor part is activated.
- The link is *not* refreshed when the active editor in the
CompareEditor is changed, either due to user input, or the editor input
becoming available. The ILinkHelper is only consulted on
'partActivated'.

Change-Id: I2bbb4b9aac2826a8880e626782369a49228d88ad
Signed-off-by: Rolf Theunissen <rolf.theunissen@altran.com>

1 files changed, 48 insertions, 0 deletions

diff --git a/bundles/org.eclipse.compare/compare/org/eclipse/compare/internal/CompareLinkHelper.java b/bundles/org.eclipse.compare/compare/org/eclipse/compare/internal/CompareLinkHelper.java
new file mode 100644
index 000000000..dc5fdc956
--- /dev/null
+++ b/bundles/org.eclipse.compare/compare/org/eclipse/compare/internal/CompareLinkHelper.java
@@ -0,0 +1,48 @@
+/*******************************************************************************
+ * Copyright (c) 2019 IBM Corporation 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:
+ * Rolf Theunissen - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.compare.internal;
+
+import org.eclipse.core.resources.IFile;
+import org.eclipse.jface.viewers.IStructuredSelection;
+import org.eclipse.jface.viewers.StructuredSelection;
+import org.eclipse.ui.IEditorInput;
+import org.eclipse.ui.IWorkbenchPage;
+import org.eclipse.ui.ide.ResourceUtil;
+import org.eclipse.ui.navigator.ILinkHelper;
+
+/**
+ * Links CompareEditorInput to IFiles in the CommonNavigator.
+ *
+ * @since 3.8
+ */
+public class CompareLinkHelper implements ILinkHelper {
+
+	@Override
+	public IStructuredSelection findSelection(IEditorInput anInput) {
+		IEditorInput eInput = anInput.getAdapter(IEditorInput.class);
+
+		IFile file = ResourceUtil.getFile(eInput);
+		if (file != null) {
+			return new StructuredSelection(file);
+		}
+
+		return StructuredSelection.EMPTY;
+	}
+
+	@Override
+	public void activateEditor(IWorkbenchPage aPage, IStructuredSelection aSelection) {
+		// do nothing
+	}
+
+}