[gtk/wip/chergert/textundo: 4/8] gtk-demo: wrap text operations in irreversible actions

[Christian Hergert <chergert src gnome org>]

commit c536a2b9b83620d3a7a80e3a0de9fd0528c8a934
Author: Christian Hergert <chergert redhat com>
Date:   Fri Nov 1 11:18:21 2019 -0700

    gtk-demo: wrap text operations in irreversible actions
    
    This ensures that the actions to set the text for the demo tabs cannot
    be undone. This matches the previous behavior for GtkTextBuffer.

 demos/gtk-demo/main.c | 5 +++++
 1 file changed, 5 insertions(+)
---
diff --git a/demos/gtk-demo/main.c b/demos/gtk-demo/main.c
index 6460f10388..a188fc3318 100644
--- a/demos/gtk-demo/main.c
+++ b/demos/gtk-demo/main.c
@@ -748,6 +748,9 @@ load_file (const gchar *demoname,
 
   source_buffer = gtk_text_buffer_new (NULL);
 
+  gtk_text_buffer_begin_irreversible_action (info_buffer);
+  gtk_text_buffer_begin_irreversible_action (source_buffer);
+
   resource_filename = g_strconcat ("/sources/", filename, NULL);
   bytes = g_resources_lookup_data (resource_filename, 0, &err);
   g_free (resource_filename);
@@ -880,9 +883,11 @@ load_file (const gchar *demoname,
 
   fontify (source_buffer);
 
+  gtk_text_buffer_end_irreversible_action (source_buffer);
   gtk_text_view_set_buffer (GTK_TEXT_VIEW (source_view), source_buffer);
   g_object_unref (source_buffer);
 
+  gtk_text_buffer_end_irreversible_action (info_buffer);
   gtk_text_view_set_buffer (GTK_TEXT_VIEW (info_view), info_buffer);
   g_object_unref (info_buffer);
 }