Catch Action* exceptions and present message box

Author: Dominic Price

client_server/Actions.cc

@@ -5,6 +5,7 @@
 #include "DocumentThread.hh"
 #include "GUIBase.hh"
 
+#include <boost/core/demangle.hpp>
 #include <iostream>
 
 using namespace cadabra;
@@ -29,7 +30,8 @@ void ActionBase::execute(DocumentThread& cl, GUIBase& )
 			}
 		++it;
 		}
-	throw std::logic_error("ActionAddCell: cannot find cell with id "+std::to_string(ref_id.id));
+	std::string class_name = boost::core::demangle(typeid(*this).name());
+	throw std::logic_error(class_name + ": cannot find cell with id "+std::to_string(ref_id.id));
 	}
 
 ActionAddCell::ActionAddCell(DataCell cell, DataCell::id_t ref_id, Position pos_)

client_server/DocumentThread.cc

@@ -187,7 +187,12 @@ void DocumentThread::process_action_queue()
 		// Execute the action; this will run synchronously, so after
 		// this returns the doc and visual representation have both been
 		// updated.
-		ab->execute(*this, *gui);
+		try {
+			ab->execute(*this, *gui);
+		}
+		catch (const std::exception& err) {
+			on_unhandled_error(err);
+		}
 		// Lock the queue to remove the action just executed, and
 		// add it to the undo stack.
 		stack_mutex.lock();
@@ -198,6 +203,10 @@ void DocumentThread::process_action_queue()
 	stack_mutex.unlock();
 	}
 
+bool DocumentThread::on_unhandled_error(const std::exception& err)
+	{
+	return true;
+	}
 
 DocumentThread::Prefs::Prefs(bool use_defaults)
 	{

client_server/DocumentThread.hh

@@ -151,6 +151,7 @@ namespace cadabra {
 			/// while this is running. So a running action can add more actions.
 
 			void                                             process_action_queue();
+			virtual bool on_unhandled_error(const std::exception& err);
 
 
 

frontend/gtkmm/NotebookWindow.cc

@@ -591,6 +591,13 @@ bool NotebookWindow::on_configure_event(GdkEventConfigure *cfg)
 	return ret;
 	}
 
+bool NotebookWindow::on_unhandled_error(const std::exception& err)
+{
+	Gtk::MessageDialog md(*this, err.what(), false, Gtk::MessageType::MESSAGE_ERROR, Gtk::ButtonsType::BUTTONS_OK, true);
+	md.run();
+	return true;
+}
+
 void NotebookWindow::set_title_prefix(const std::string& pf)
 	{
 	title_prefix=pf;

frontend/gtkmm/NotebookWindow.hh

@@ -115,6 +115,7 @@ namespace cadabra {
 			virtual bool on_key_press_event(GdkEventKey*) override;
 			virtual bool on_delete_event(GdkEventAny*) override;
 			virtual bool on_configure_event(GdkEventConfigure *cfg) override;
+			virtual bool on_unhandled_error(const std::exception& err) override;
 
 			DTree::iterator current_cell;