[gtk+] textview: Make "extend selection" only extend

[Carlos Garnacho <carlosg src gnome org>]

commit 8c091d1484c7b269b302a03212df37a785aae55e
Author: Carlos Garnacho <carlosg gnome org>
Date:   Thu Nov 20 14:03:07 2014 +0100

    textview: Make "extend selection" only extend
    
    This mode could also shrink the selection, plus the starting point would
    seem somewhat arbitrary (actually dependent on the dragging direction of
    the last selection).
    
    Made this mode more consistent by only allowing it to extend the selection,
    only in one direction for each operation, and so it keeps the current
    selection as a minimum.

 gtk/gtktextview.c |   20 ++++++++++++--------
 1 files changed, 12 insertions(+), 8 deletions(-)
---
diff --git a/gtk/gtktextview.c b/gtk/gtktextview.c
index 33a0751..f41590c 100644
--- a/gtk/gtktextview.c
+++ b/gtk/gtktextview.c
@@ -7161,10 +7161,11 @@ gtk_text_view_drag_gesture_update (GtkGestureDrag *gesture,
       extend_selection (text_view, data->granularity, &cursor, &start, &end);
 
       /* either the selection extends to the front, or end (or not) */
-      if (gtk_text_iter_compare (&cursor, &orig_start) < 0)
-        gtk_text_buffer_select_range (buffer, &start, &orig_end);
-      else
-        gtk_text_buffer_select_range (buffer, &end, &orig_start);
+      if (gtk_text_iter_compare (&orig_start, &start) < 0)
+        start = orig_start;
+      if (gtk_text_iter_compare (&orig_end, &end) > 0)
+        end = orig_end;
+      gtk_text_buffer_select_range (buffer, &start, &end);
 
       gtk_text_view_scroll_mark_onscreen (text_view,
                                          gtk_text_buffer_get_insert (buffer));
@@ -7313,15 +7314,18 @@ gtk_text_view_start_selection_drag (GtkTextView          *text_view,
            gtk_text_iter_compare (&old_ins, &old_bound) <= 0))
         {
           bound = old_end;
-          orig_start = old_end;
-          orig_end = old_end;
         }
       else
         {
           ins = bound;
           bound = old_start;
-          orig_end = bound;
-          orig_start = bound;
+        }
+
+      /* Store any previous selection */
+      if (gtk_text_iter_compare (&old_start, &old_end) != 0)
+        {
+          orig_start = old_ins;
+          orig_end = old_bound;
         }
     }