Provide variable substitution selection dialog

plugin/META-INF/MANIFEST.MF

@@ -15,7 +15,8 @@ Require-Bundle: org.eclipse.ui,
  org.eclipse.cdt.ui;resolution:=optional,
  org.eclipse.cdt.core;resolution:=optional,
  org.eclipse.ui.workbench.texteditor,
- org.eclipse.jface.text
+ org.eclipse.jface.text,
+ org.eclipse.debug.ui
 Bundle-RequiredExecutionEnvironment: JavaSE-11
 Bundle-ActivationPolicy: lazy
 Bundle-ClassPath: target/easyshell-library.jar

plugin/plugin.xml

@@ -235,5 +235,12 @@
             name="EasyShell All (Multiple Action)">
       </editor>
    </extension>
+   <extension
+         point="org.eclipse.debug.ui.stringVariablePresentations">
+      <variablePresentation
+            argumentSelector="de.anbos.eclipse.easyshell.plugin.misc.DynamicVariableSelector"
+            variableName="easyshell">
+      </variablePresentation>
+   </extension>
 
 </plugin>

plugin/src/de/anbos/eclipse/easyshell/plugin/misc/DynamicVariableSelector.java

@@ -0,0 +1,28 @@
+package de.anbos.eclipse.easyshell.plugin.misc;
+
+import org.eclipse.core.variables.IStringVariable;
+import org.eclipse.debug.ui.stringsubstitution.IArgumentSelector;
+import org.eclipse.jface.viewers.LabelProvider;
+import org.eclipse.jface.window.Window;
+import org.eclipse.swt.widgets.Shell;
+import org.eclipse.ui.dialogs.ElementListSelectionDialog;
+
+import de.anbos.eclipse.easyshell.plugin.types.Variable;
+
+public class DynamicVariableSelector implements IArgumentSelector {
+
+	@Override
+	public String selectArgument(IStringVariable stringVariable, Shell shell) {
+		ElementListSelectionDialog dialog = new ElementListSelectionDialog(shell, new LabelProvider());
+		var varNames = Variable.getVisibleVariables().stream().map(variable -> variable.getName()).sorted()
+				.toArray(String[]::new);
+		dialog.setElements(varNames);
+		dialog.setTitle("Select EasyShell Variable");
+		dialog.setMessage("Select an EasyShell variable (? = any character, * = any String):");
+		if (dialog.open() == Window.OK) {
+			return (String) dialog.getResult()[0];
+		}
+		return null;
+	}
+
+}