Bug 579247 - Commands for multi-selection not available in multipage editor Change-Id: Ibcd40039339b3ba2c6e79820d3f840640abe95e5 Reviewed-on: https://git.eclipse.org/r/c/platform/eclipse.platform.text/+/191917 Tested-by: Platform Bot <platform-bot@eclipse.org> Reviewed-by: Mickael Istria <mistria@redhat.com>

diff --git a/org.eclipse.ui.workbench.texteditor/plugin.xml b/org.eclipse.ui.workbench.texteditor/plugin.xml
index 70d47cf..9dea32d 100644
--- a/org.eclipse.ui.workbench.texteditor/plugin.xml
+++ b/org.eclipse.ui.workbench.texteditor/plugin.xml

@@ -1381,60 +1381,45 @@
             class="org.eclipse.ui.internal.texteditor.ToMultiSelectionHandler"
             commandId="org.eclipse.ui.edit.text.toMultiSelection">
          <enabledWhen>
-            <with
-                 variable="activeEditor">
-              <instanceof
-                    value="org.eclipse.ui.texteditor.ITextEditor">
-              </instanceof>
-           </with>
+            <with variable="activeEditor">
+              <adapt type="org.eclipse.ui.texteditor.ITextEditor"/>
+            </with>
          </enabledWhen>
       </handler>
       <handler
             class="org.eclipse.ui.internal.texteditor.multiselection.AddAllMatchesToMultiSelectionHandler"
             commandId="org.eclipse.ui.edit.text.select.addAllMatchesToMultiSelection">
          <enabledWhen>
-            <with
-                 variable="activeEditor">
-              <instanceof
-                    value="org.eclipse.ui.texteditor.ITextEditor">
-              </instanceof>
-           </with>
+            <with variable="activeEditor">
+              <adapt type="org.eclipse.ui.texteditor.ITextEditor"/>
+            </with>
          </enabledWhen>
       </handler>	
       <handler
             class="org.eclipse.ui.internal.texteditor.multiselection.MultiSelectionDownHandler"
             commandId="org.eclipse.ui.edit.text.select.selectMultiSelectionDown">
          <enabledWhen>
-            <with
-                 variable="activeEditor">
-              <instanceof
-                    value="org.eclipse.ui.texteditor.ITextEditor">
-              </instanceof>
-           </with>
+            <with variable="activeEditor">
+              <adapt type="org.eclipse.ui.texteditor.ITextEditor"/>
+            </with>
          </enabledWhen>
       </handler>
       <handler
             class="org.eclipse.ui.internal.texteditor.multiselection.MultiSelectionUpHandler"
             commandId="org.eclipse.ui.edit.text.select.selectMultiSelectionUp">
          <enabledWhen>
-            <with
-                 variable="activeEditor">
-              <instanceof
-                    value="org.eclipse.ui.texteditor.ITextEditor">
-              </instanceof>
-           </with>
+            <with variable="activeEditor">
+              <adapt type="org.eclipse.ui.texteditor.ITextEditor"/>
+            </with>
          </enabledWhen>
       </handler>
       <handler
             class="org.eclipse.ui.internal.texteditor.multiselection.StopMultiSelectionHandler"
             commandId="org.eclipse.ui.edit.text.select.stopMultiSelection">
          <enabledWhen>
-            <with
-                 variable="activeEditor">
-              <instanceof
-                    value="org.eclipse.ui.texteditor.ITextEditor">
-              </instanceof>
-           </with>
+            <with variable="activeEditor">
+              <adapt type="org.eclipse.ui.texteditor.ITextEditor"/>
+            </with>
          </enabledWhen>
       </handler>
    </extension>

diff --git a/org.eclipse.ui.workbench.texteditor/src/org/eclipse/ui/internal/texteditor/ToMultiSelectionHandler.java b/org.eclipse.ui.workbench.texteditor/src/org/eclipse/ui/internal/texteditor/ToMultiSelectionHandler.java
index 0fda409..ee9ebaf 100644
--- a/org.eclipse.ui.workbench.texteditor/src/org/eclipse/ui/internal/texteditor/ToMultiSelectionHandler.java
+++ b/org.eclipse.ui.workbench.texteditor/src/org/eclipse/ui/internal/texteditor/ToMultiSelectionHandler.java

@@ -14,6 +14,8 @@
 import org.eclipse.core.commands.ExecutionEvent;
 import org.eclipse.core.commands.ExecutionException;
 
+import org.eclipse.core.runtime.Adapters;
+
 import org.eclipse.jface.viewers.ISelection;
 
 import org.eclipse.jface.text.IBlockTextSelection;
@@ -33,10 +35,10 @@
 	@Override
 	public Object execute(ExecutionEvent event) throws ExecutionException {
 		IEditorPart editor = HandlerUtil.getActiveEditor(event);
-		if (!(editor instanceof ITextEditor)) {
+		ITextEditor textEditor = Adapters.adapt(editor, ITextEditor.class);
+		if (textEditor == null) {
 			return null;
 		}
-		ITextEditor textEditor = (ITextEditor) editor;
 		ISelection selection = textEditor.getSelectionProvider().getSelection();
 		if (!(selection instanceof IBlockTextSelection)) {
 			return null;

diff --git a/org.eclipse.ui.workbench.texteditor/src/org/eclipse/ui/internal/texteditor/multiselection/AbstractMultiSelectionHandler.java b/org.eclipse.ui.workbench.texteditor/src/org/eclipse/ui/internal/texteditor/multiselection/AbstractMultiSelectionHandler.java
index ba42de9..f16c20b 100644
--- a/org.eclipse.ui.workbench.texteditor/src/org/eclipse/ui/internal/texteditor/multiselection/AbstractMultiSelectionHandler.java
+++ b/org.eclipse.ui.workbench.texteditor/src/org/eclipse/ui/internal/texteditor/multiselection/AbstractMultiSelectionHandler.java

@@ -24,6 +24,8 @@
 import org.eclipse.core.commands.ExecutionEvent;
 import org.eclipse.core.commands.ExecutionException;
 
+import org.eclipse.core.runtime.Adapters;
+
 import org.eclipse.jface.viewers.ISelection;
 
 import org.eclipse.jface.text.BadLocationException;
@@ -320,7 +322,7 @@
 
 	private void initTextEditor() {
 		IEditorPart editor = HandlerUtil.getActiveEditor(event);
-		textEditor = editor instanceof ITextEditor ? (ITextEditor) editor : null;
+		textEditor = Adapters.adapt(editor, ITextEditor.class);
 	}
 
 	private IDocument getDocument() {