[gnome-builder] sourceview: fix duplicate-entire-line when at EOL

[Christian Hergert <chergert src gnome org>]

commit 666c7ff1829eced1b8c9948df2b1440ef0f50efd
Author: Christian Hergert <chergert redhat com>
Date:   Tue Jul 23 12:47:52 2019 -0700

    sourceview: fix duplicate-entire-line when at EOL
    
    If we are at the end of the line, moving to the line end will
    cause us to advance to the line end on the following line. Doing
    so results in not copying the line.
    
    Fixes #981

 src/libide/sourceview/ide-source-view.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)
---
diff --git a/src/libide/sourceview/ide-source-view.c b/src/libide/sourceview/ide-source-view.c
index 3228a9c8b..331627fa0 100644
--- a/src/libide/sourceview/ide-source-view.c
+++ b/src/libide/sourceview/ide-source-view.c
@@ -2938,7 +2938,9 @@ ide_source_view_real_duplicate_entire_line (IdeSourceView *self)
       end = begin;
 
       gtk_text_iter_set_line_offset (&begin, 0);
-      gtk_text_iter_forward_to_line_end (&end);
+
+      if (!gtk_text_iter_ends_line (&end))
+        gtk_text_iter_forward_to_line_end (&end);
 
       if (gtk_text_iter_get_line (&begin) == gtk_text_iter_get_line (&end))
         {