Fix dependency issue by introducing IHandlerWithExpression interface

Co-authored-by: laeubi <1331477+laeubi@users.noreply.github.com>

Author: Copilot

bundles/org.eclipse.e4.core.commands/src/org/eclipse/e4/core/commands/IHandlerWithExpression.java

@@ -0,0 +1,42 @@
+/*******************************************************************************
+ * Copyright (c) 2025 Eclipse Platform 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:
+ *     Eclipse Platform - initial API and implementation
+ ******************************************************************************/
+
+package org.eclipse.e4.core.commands;
+
+import org.eclipse.e4.core.contexts.IEclipseContext;
+
+/**
+ * A marker interface for handlers that have enabledWhen expressions that need to be
+ * evaluated before @CanExecute.
+ *
+ * @since 1.1
+ * @noimplement This interface is not intended to be implemented by clients outside of the
+ *              workbench.
+ */
+public interface IHandlerWithExpression {
+	/**
+	 * Evaluates the enabledWhen expression if present.
+	 *
+	 * @param context the eclipse context for evaluation
+	 * @return true if no expression is defined or if the expression evaluates to true
+	 */
+	boolean evaluateEnabledWhen(IEclipseContext context);
+
+	/**
+	 * Returns the actual handler object that should be used for execution.
+	 *
+	 * @return the handler object
+	 */
+	Object getHandler();
+}

bundles/org.eclipse.e4.core.commands/src/org/eclipse/e4/core/commands/internal/HandlerServiceHandler.java

@@ -25,6 +25,7 @@
 import org.eclipse.core.commands.State;
 import org.eclipse.core.expressions.IEvaluationContext;
 import org.eclipse.e4.core.commands.ExpressionContext;
+import org.eclipse.e4.core.commands.IHandlerWithExpression;
 import org.eclipse.e4.core.commands.internal.HandlerServiceImpl.ExecutionContexts;
 import org.eclipse.e4.core.contexts.ContextInjectionFactory;
 import org.eclipse.e4.core.contexts.EclipseContextFactory;
@@ -67,14 +68,13 @@ public boolean isEnabled() {
 
 		// Check for enabledWhen expression first (takes precedence over @CanExecute)
 		Object actualHandler = handler;
-		if (handler instanceof org.eclipse.e4.ui.internal.workbench.addons.HandlerEnabledWhenWrapper) {
-			org.eclipse.e4.ui.internal.workbench.addons.HandlerEnabledWhenWrapper wrapper =
-					(org.eclipse.e4.ui.internal.workbench.addons.HandlerEnabledWhenWrapper) handler;
-			if (!wrapper.evaluateEnabledWhen(executionContext)) {
+		if (handler instanceof IHandlerWithExpression) {
+			IHandlerWithExpression handlerWithExpr = (IHandlerWithExpression) handler;
+			if (!handlerWithExpr.evaluateEnabledWhen(executionContext)) {
 				setBaseEnabled(false);
 				return super.isEnabled();
 			}
-			actualHandler = wrapper.getHandler();
+			actualHandler = handlerWithExpr.getHandler();
 		}
 
 		IEclipseContext staticContext = contexts.staticContext; // getStaticContext(contexts);
@@ -99,8 +99,8 @@ public void setEnabled(Object evaluationContext) {
 
 		// Unwrap handler if needed
 		Object actualHandler = handler;
-		if (handler instanceof org.eclipse.e4.ui.internal.workbench.addons.HandlerEnabledWhenWrapper) {
-			actualHandler = ((org.eclipse.e4.ui.internal.workbench.addons.HandlerEnabledWhenWrapper) handler).getHandler();
+		if (handler instanceof IHandlerWithExpression) {
+			actualHandler = ((IHandlerWithExpression) handler).getHandler();
 		}
 
 		IEclipseContext staticContext = getStaticContext(executionContext);
@@ -155,8 +155,8 @@ public boolean isHandled() {
 
 			// Unwrap handler if needed
 			Object actualHandler = handler;
-			if (handler instanceof org.eclipse.e4.ui.internal.workbench.addons.HandlerEnabledWhenWrapper) {
-				actualHandler = ((org.eclipse.e4.ui.internal.workbench.addons.HandlerEnabledWhenWrapper) handler).getHandler();
+			if (handler instanceof IHandlerWithExpression) {
+				actualHandler = ((IHandlerWithExpression) handler).getHandler();
 			}
 
 			if (actualHandler instanceof IHandler) {
@@ -184,8 +184,8 @@ public Object execute(ExecutionEvent event) throws ExecutionException {
 
 		// Unwrap handler if needed
 		Object actualHandler = handler;
-		if (handler instanceof org.eclipse.e4.ui.internal.workbench.addons.HandlerEnabledWhenWrapper) {
-			actualHandler = ((org.eclipse.e4.ui.internal.workbench.addons.HandlerEnabledWhenWrapper) handler).getHandler();
+		if (handler instanceof IHandlerWithExpression) {
+			actualHandler = ((IHandlerWithExpression) handler).getHandler();
 		}
 
 		IEclipseContext staticContext = getStaticContext(executionContext);

bundles/org.eclipse.e4.ui.workbench/src/org/eclipse/e4/ui/internal/workbench/addons/HandlerEnabledWhenWrapper.java

@@ -18,6 +18,7 @@
 import org.eclipse.core.expressions.Expression;
 import org.eclipse.core.expressions.ReferenceExpression;
 import org.eclipse.e4.core.commands.ExpressionContext;
+import org.eclipse.e4.core.commands.IHandlerWithExpression;
 import org.eclipse.e4.core.contexts.IEclipseContext;
 import org.eclipse.e4.ui.model.application.commands.MHandler;
 import org.eclipse.e4.ui.model.application.ui.MCoreExpression;
@@ -29,7 +30,7 @@
  *
  * @since 1.4
  */
-public class HandlerEnabledWhenWrapper {
+public class HandlerEnabledWhenWrapper implements IHandlerWithExpression {
 	private final Object handler;
 	private final MHandler handlerModel;
 
@@ -38,6 +39,7 @@ public HandlerEnabledWhenWrapper(Object handler, MHandler handlerModel) {
 		this.handlerModel = handlerModel;
 	}
 
+	@Override
 	public Object getHandler() {
 		return handler;
 	}
@@ -46,12 +48,7 @@ public MHandler getHandlerModel() {
 		return handlerModel;
 	}
 
-	/**
-	 * Evaluates the enabledWhen expression if present.
-	 *
-	 * @param context the eclipse context for evaluation
-	 * @return true if no expression is defined or if the expression evaluates to true
-	 */
+	@Override
 	public boolean evaluateEnabledWhen(IEclipseContext context) {
 		MExpression enabledWhen = handlerModel.getEnabledWhen();
 		if (enabledWhen == null) {

tests/org.eclipse.e4.ui.tests/src/org/eclipse/e4/ui/tests/workbench/HandlerEnabledWhenTest.java

@@ -135,6 +135,7 @@ public void testEnabledWhenTrue() throws Exception {
 		MHandler handlerModel = createHandlerWithExpression(handler, new TrueExpression());
 
 		// Use the wrapper created by HandlerProcessingAddon simulation
+		// The wrapper implements IHandlerWithExpression interface
 		org.eclipse.e4.ui.internal.workbench.addons.HandlerEnabledWhenWrapper wrapper = 
 				new org.eclipse.e4.ui.internal.workbench.addons.HandlerEnabledWhenWrapper(handler, handlerModel);
 		service.activateHandler(TEST_COMMAND_ID, wrapper);