[gtksourceview] Fix corner case in join lines

[Paolo Borelli <pborelli src gnome org>]

commit d862246aeb1ee47791e55b5b778f8a4cb5d4c0a9
Author: Paolo Borelli <pborelli gnome org>
Date:   Thu Mar 12 14:27:36 2015 +0100

    Fix corner case in join lines
    
    https://bugzilla.gnome.org/show_bug.cgi?id=746056

 gtksourceview/gtksourcebuffer.c |   17 +++++++++--------
 1 files changed, 9 insertions(+), 8 deletions(-)
---
diff --git a/gtksourceview/gtksourcebuffer.c b/gtksourceview/gtksourcebuffer.c
index c9ab977..d3ce2f4 100644
--- a/gtksourceview/gtksourcebuffer.c
+++ b/gtksourceview/gtksourcebuffer.c
@@ -2580,11 +2580,6 @@ gtk_source_buffer_join_lines (GtkSourceBuffer *buffer,
        g_return_if_fail (start != NULL);
        g_return_if_fail (end != NULL);
 
-       if (gtk_text_iter_get_line (start) == gtk_text_iter_get_line (end))
-       {
-               return;
-       }
-
        gtk_text_iter_order (start, end);
 
        text_buffer = GTK_TEXT_BUFFER (buffer);
@@ -2594,10 +2589,11 @@ gtk_source_buffer_join_lines (GtkSourceBuffer *buffer,
 
        move_to_line_text_end (start);
 
-       while (gtk_text_iter_compare (start, end) < 0)
+       while (gtk_text_iter_get_line (start) < gtk_text_iter_get_line (end))
        {
                GtkTextIter iter;
                gunichar ch;
+               gboolean insert_space = FALSE;
 
                iter = *start;
 
@@ -2606,14 +2602,19 @@ gtk_source_buffer_join_lines (GtkSourceBuffer *buffer,
                        ch = gtk_text_iter_get_char (&iter);
                        if (!g_unichar_isspace (ch))
                        {
+                               insert_space = TRUE;
                                break;
                        }
-               } while (gtk_text_iter_forward_char (&iter));
+               } while (gtk_text_iter_forward_char (&iter) &&
+                        gtk_text_iter_compare (&iter, end) < 0);
 
                if (!gtk_text_iter_is_end (&iter))
                {
                        gtk_text_buffer_delete (text_buffer, start, &iter);
-                       gtk_text_buffer_insert (text_buffer, start, " ", 1);
+                       if (insert_space)
+                       {
+                               gtk_text_buffer_insert (text_buffer, start, " ", 1);
+                       }
                }
 
                move_to_line_text_end (start);