Fix undo of line end type change

At the moment undo of line end type change only undos the changes made
in the document but the different line ending settings remains active.

This patch fixes the issue by combining the line end scintilla undo action
with a new UNDO_EOL action responsible for updating the line ending
settings.

Fixes #409

src/callbacks.c

@@ -497,8 +497,15 @@ static void convert_eol(gint mode)
 
 	g_return_if_fail(doc != NULL);
 
+	/* sci_convert_eols() adds UNDO_SCINTILLA action in on_editor_notify().
+	 * It is added to the undo stack before sci_convert_eols() finishes
+	 * so after adding UNDO_EOL, UNDO_EOL will be at the top of the stack
+	 * and UNDO_SCINTILLA below it. */
 	sci_convert_eols(doc->editor->sci, mode);
+	document_undo_add(doc, UNDO_EOL, GINT_TO_POINTER(sci_get_eol_mode(doc->editor->sci)));
+
 	sci_set_eol_mode(doc->editor->sci, mode);
+
 	ui_update_statusbar(doc, -1);
 }
 

src/document.c

@@ -2953,6 +2953,25 @@ void document_undo(GeanyDocument *doc)
 				g_free(action->data);
 				break;
 			}
+			case UNDO_EOL:
+			{
+				undo_action *next_action;
+
+				document_redo_add(doc, UNDO_EOL, GINT_TO_POINTER(sci_get_eol_mode(doc->editor->sci)));
+
+				sci_set_eol_mode(doc->editor->sci, GPOINTER_TO_INT(action->data));
+
+				ui_update_statusbar(doc, -1);
+				ui_document_show_hide(doc);
+
+				/* When undoing, UNDO_EOL is always followed by UNDO_SCINTILLA
+				 * which undos the line endings in the editor and should be
+				 * performed together with UNDO_EOL. */
+				next_action = g_trash_stack_peek(&doc->priv->undo_actions);
+				if (next_action && next_action->type == UNDO_SCINTILLA)
+					document_undo(doc);
+				break;
+			}
 			case UNDO_RELOAD:
 			{
 				UndoReloadData *data = (UndoReloadData*)action->data;
@@ -3017,9 +3036,18 @@ void document_redo(GeanyDocument *doc)
 		{
 			case UNDO_SCINTILLA:
 			{
+				undo_action *next_action;
+
 				document_undo_add_internal(doc, UNDO_SCINTILLA, NULL);
 
 				sci_redo(doc->editor->sci);
+
+				/* When redoing an EOL change, the UNDO_SCINTILLA which changes
+				 * the line ends in the editor is followed by UNDO_EOL
+				 * which should be performed together with UNDO_SCINTILLA. */
+				next_action = g_trash_stack_peek(&doc->priv->redo_actions);
+				if (next_action != NULL && next_action->type == UNDO_EOL)
+					document_redo(doc);
 				break;
 			}
 			case UNDO_BOM:
@@ -3044,6 +3072,16 @@ void document_redo(GeanyDocument *doc)
 				g_free(action->data);
 				break;
 			}
+			case UNDO_EOL:
+			{
+				document_undo_add_internal(doc, UNDO_EOL, GINT_TO_POINTER(sci_get_eol_mode(doc->editor->sci)));
+
+				sci_set_eol_mode(doc->editor->sci, GPOINTER_TO_INT(action->data));
+
+				ui_update_statusbar(doc, -1);
+				ui_document_show_hide(doc);
+				break;
+			}
 			case UNDO_RELOAD:
 			{
 				UndoReloadData *data = (UndoReloadData*)action->data;

src/documentprivate.h

@@ -35,6 +35,7 @@ enum
 	UNDO_ENCODING,
 	UNDO_BOM,
 	UNDO_RELOAD,
+	UNDO_EOL,
 	UNDO_ACTIONS_MAX
 };