Undo/Redo will now label the menu item with the last respective action.

src/mainframe.cpp

@@ -1899,6 +1899,38 @@ ui::MenuItem create_file_menu()
 	return file_menu_item;
 }
 
+ui::MenuItem undobutton{ui::null};
+void
+Undo_SetButtonlabel(const char *title)
+{
+	StringOutputStream name(128);
+	name << "Undo ("<< title << ")";
+	gtk_menu_item_set_label(undobutton, name.c_str());
+	gtk_widget_set_sensitive(undobutton, true);
+}
+void
+Undo_DisableButton(void)
+{
+	gtk_menu_item_set_label(undobutton, "Undo");
+	gtk_widget_set_sensitive(undobutton, false);
+}
+
+ui::MenuItem redobutton{ui::null};
+void
+Redo_SetButtonlabel(const char *title)
+{
+	StringOutputStream name(128);
+	name << "Redo (" << title << ")";
+	gtk_menu_item_set_label(redobutton, name.c_str());
+	gtk_widget_set_sensitive(redobutton, true);
+}
+void
+Redo_DisableButton(void)
+{
+	gtk_menu_item_set_label(redobutton, "Redo");
+	gtk_widget_set_sensitive(redobutton, false);
+}
+
 ui::MenuItem create_edit_menu()
 {
 	// Edit menu
@@ -1907,8 +1939,10 @@ ui::MenuItem create_edit_menu()
 	/*if (g_Layout_enableOpenStepUX.m_value) {
 	    menu_tearoff(menu);
 	   }*/
-	create_menu_item_with_mnemonic(menu, "_Undo", "Undo");
+	undobutton = create_menu_item_with_mnemonic(menu, "_Undo", "Undo");
-	create_menu_item_with_mnemonic(menu, "_Redo", "Redo");
+	redobutton = create_menu_item_with_mnemonic(menu, "_Redo", "Redo");
+	gtk_menu_item_set_label(undobutton, "Undo (Nothing...)");
+	gtk_menu_item_set_label(redobutton, "Redo (Nothing...)");
 	menu_separator(menu);
 	create_menu_item_with_mnemonic(menu, "_Copy", "Copy");
 	create_menu_item_with_mnemonic(menu, "_Paste", "Paste");

src/undo.cpp

@@ -37,6 +37,12 @@
 
 #include "timer.h"
 
+void Undo_SetButtonlabel(const char *title);
+void Undo_DisableButton(void);
+
+void Redo_SetButtonlabel(const char *title);
+void Redo_DisableButton(void);
+
 class DebugScopeTimer {
 Timer m_timer;
 const char *m_operation;
@@ -363,6 +369,8 @@ void finish(const char *command)
 {
 	if (finishUndo(command)) {
 		globalOutputStream() << command << '\n';
+		Undo_SetButtonlabel(command);
+		Redo_DisableButton();
 	}
 }
 
@@ -373,12 +381,19 @@ void undo()
 	} else {
 		Operation *operation = m_undo_stack.back();
 		globalOutputStream() << "Undo: " << operation->m_command.c_str() << "\n";
+		Redo_SetButtonlabel(operation->m_command.c_str());
 
 		startRedo();
 		trackersUndo();
 		operation->m_snapshot.restore();
 		finishRedo(operation->m_command.c_str());
 		m_undo_stack.pop_back();
+
+		Operation *operation2 = m_undo_stack.back();
+		if (operation2) {
+			Undo_SetButtonlabel(operation2->m_command.c_str());
+		} else
+			Undo_DisableButton();
 	}
 }
 
@@ -395,6 +410,14 @@ void redo()
 		operation->m_snapshot.restore();
 		finishUndo(operation->m_command.c_str());
 		m_redo_stack.pop_back();
+		Operation *operationu = m_undo_stack.back();
+		Undo_SetButtonlabel(operationu->m_command.c_str());
+
+		Operation *next = m_redo_stack.back();
+		if (!next)
+			Redo_DisableButton();
+		else
+			Redo_SetButtonlabel(next->m_command.c_str());
 	}
 }