[gnome-builder] gtk: add helper to get GtkTextIter's previous char.

[Christian Hergert <chergert src gnome org>]

commit 0372df8272f68cdbdb5b1e37e3d629475270c8a8
Author: Christian Hergert <christian hergert me>
Date:   Fri Jan 2 15:43:47 2015 -0800

    gtk: add helper to get GtkTextIter's previous char.

 src/util/gb-gtk.c |   16 ++++++++++++++++
 src/util/gb-gtk.h |    2 ++
 2 files changed, 18 insertions(+), 0 deletions(-)
---
diff --git a/src/util/gb-gtk.c b/src/util/gb-gtk.c
index c6e77b5..d8d0fff 100644
--- a/src/util/gb-gtk.c
+++ b/src/util/gb-gtk.c
@@ -154,3 +154,19 @@ gb_gtk_text_view_get_iter_visible (GtkTextView *text_view,
 
   return gdk_rectangle_intersect (&visible_rect, &iter_location, NULL);
 }
+
+gunichar
+gb_gtk_text_iter_get_previous_char (const GtkTextIter *iter)
+{
+  GtkTextIter copy;
+
+  g_return_val_if_fail (iter, 0);
+
+  copy = *iter;
+
+  gtk_text_iter_backward_char (&copy);
+  if (gtk_text_iter_equal (&copy, iter))
+    return '\0';
+
+  return gtk_text_iter_get_char (&copy);
+}
diff --git a/src/util/gb-gtk.h b/src/util/gb-gtk.h
index 66304c4..c7a79e6 100644
--- a/src/util/gb-gtk.h
+++ b/src/util/gb-gtk.h
@@ -38,6 +38,8 @@ void gb_gtk_text_view_scroll_to_iter (GtkTextView *text_view,
 gboolean gb_gtk_text_view_get_iter_visible (GtkTextView *text_view,
                                             GtkTextIter *iter);
 
+gunichar gb_gtk_text_iter_get_previous_char (const GtkTextIter *iter);
+
 G_END_DECLS
 
 #endif /* GB_GTK_H */