Fix crash when grouping by key press and no nodes selected.

Author: kovacsv

Sources/NodeUIEngine/NUIE_InteractionHandler.cpp

@@ -841,7 +841,9 @@ EventHandlerResult InteractionHandler::HandleKeyPress (NodeUIEnvironment& env, c
 	switch (pressedKey.GetKeyCode ()) {
 		case KeyCode::Delete:
 			{
-				command.reset (new DeleteNodesMenuCommand (uiManager, env, selectedNodes));
+				if (!selectedNodes.IsEmpty ()) {
+					command.reset (new DeleteNodesMenuCommand (uiManager, env, selectedNodes));
+				}
 			}
 			break;
 		case KeyCode::SelectAll:
@@ -856,18 +858,24 @@ EventHandlerResult InteractionHandler::HandleKeyPress (NodeUIEnvironment& env, c
 			break;
 		case KeyCode::Copy:
 			{
-				command.reset (new CopyNodesMenuCommand (uiManager, selectedNodes));
+				if (!selectedNodes.IsEmpty ()) {
+					command.reset (new CopyNodesMenuCommand (uiManager, selectedNodes));
+				}
 			}
 			break;
 		case KeyCode::Paste:
 			{
-				Point modelPastePosition = pastePositionCalculator.CalculatePastePosition (uiManager, env);
-				command.reset (new PasteNodesMenuCommand (uiManager, modelPastePosition));
+				if (uiManager.CanPaste ()) {
+					Point modelPastePosition = pastePositionCalculator.CalculatePastePosition (uiManager, env);
+					command.reset (new PasteNodesMenuCommand (uiManager, modelPastePosition));
+				}
 			}
 			break;
 		case KeyCode::Group:
 			{
-				command.reset (new CreateGroupMenuCommand (uiManager, selectedNodes));
+				if (!selectedNodes.IsEmpty ()) {
+					command.reset (new CreateGroupMenuCommand (uiManager, selectedNodes));
+				}
 			}
 			break;
 		case KeyCode::Undo:

Sources/NodeUIEngine/NUIE_NodeUIManagerCommands.cpp

@@ -54,6 +54,9 @@ DeleteNodesCommand::DeleteNodesCommand (const NE::NodeCollection& nodes, NE::Eva
 
 void DeleteNodesCommand::Do (NodeUIManager& uiManager)
 {
+	if (DBGERROR (nodes.IsEmpty ())) {
+		return;
+	}
 	nodes.Enumerate ([&] (const NE::NodeId& nodeId) {
 		uiManager.DeleteNode (nodeId, evaluationEnv);
 		return true;
@@ -198,6 +201,9 @@ CopyNodesCommand::CopyNodesCommand (const NE::NodeCollection& nodes) :
 
 void CopyNodesCommand::Do (NodeUIManager& uiManager)
 {
+	if (DBGERROR (nodes.IsEmpty ())) {
+		return;
+	}
 	uiManager.Copy (nodes);
 }
 
@@ -209,6 +215,10 @@ PasteNodesCommand::PasteNodesCommand (const Point& position) :
 
 void PasteNodesCommand::Do (NodeUIManager& uiManager)
 {
+	if (DBGERROR (!uiManager.CanPaste ())) {
+		return;
+	}
+
 	std::unordered_set<NE::NodeId> oldNodes;
 	uiManager.EnumerateUINodes ([&] (const UINodeConstPtr& uiNode) {
 		oldNodes.insert (uiNode->GetId ());
@@ -253,6 +263,9 @@ AddGroupCommand::AddGroupCommand (const UINodeGroupPtr& uiGroup, const NE::NodeC
 
 void AddGroupCommand::Do (NodeUIManager& uiManager)
 {
+	if (DBGERROR (nodes.IsEmpty ())) {
+		return;
+	}
 	uiManager.AddUINodeGroup (uiGroup);
 	uiManager.AddNodesToUIGroup (uiGroup, nodes);
 }