[gedit] Fix Bug 734185 - Python debug_plugin_message results in AttributeError or wrong file/line

[Paolo Borelli <pborelli src gnome org>]

commit fadfe8492d52695f4499826a53c1357d7bea3eaf
Author: Daniel Trebbien <dtrebbien gmail com>
Date:   Sun Sep 14 08:49:17 2014 -0400

    Fix Bug 734185 - Python debug_plugin_message results in AttributeError or wrong file/line
    
    Before overwriting the `frame` local variable, check that `frame.f_back`
    is not None. Also, change the `num_back_frames` argument to get_trace_info()
    in the debug_plugin_message() override from 2 to 1 because the @override
    decorator had one level of indirection removed.

 gedit/Gedit.py |    7 +++++--
 1 files changed, 5 insertions(+), 2 deletions(-)
---
diff --git a/gedit/Gedit.py b/gedit/Gedit.py
index 4bf9e06..5aed5f9 100644
--- a/gedit/Gedit.py
+++ b/gedit/Gedit.py
@@ -49,7 +49,10 @@ def get_trace_info(num_back_frames=0):
     frame = inspect.currentframe().f_back
     try:
         for i in range(num_back_frames):
-            frame = frame.f_back
+            back_frame = frame.f_back
+            if back_frame == None:
+                break
+            frame = back_frame
 
         filename = frame.f_code.co_filename
 
@@ -73,7 +76,7 @@ orig_debug_plugin_message_func = Gedit.debug_plugin_message
 
 @override(Gedit.debug_plugin_message)
 def debug_plugin_message(format, *format_args):
-    filename, lineno, func_name = get_trace_info(2)
+    filename, lineno, func_name = get_trace_info(1)
     orig_debug_plugin_message_func(filename, lineno, func_name, format % format_args)
 __all__.append(debug_plugin_message)