id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc
4653	TypeError: unsupported operand type(s) for +: 'NoneType' and 'NoneType'	anonymous	somebody	"==== How to Reproduce ====

While doing a GET operation on `/changeset/fe3edfceb59f84e056a84224c012a59e26fe39f9/OpenModelica`, Trac issued an internal error.

''Trying to view existing OMEdit ticket 4670866''

Request parameters:
{{{
{'new': u'fe3edfceb59f84e056a84224c012a59e26fe39f9',
 'new_path': u'/OpenModelica'}
}}}

User agent: `Mozilla/5.0 (Windows NT 10.0; WOW64; Trident/7.0; .NET4.0C; .NET4.0E; .NET CLR 2.0.50727; .NET CLR 3.0.30729; .NET CLR 3.5.30729; rv:11.0) like Gecko`

==== System Information ====
''System information not available''

==== Enabled Plugins ====
''Plugin information not available''

==== Python Traceback ====
{{{
Traceback (most recent call last):
  File ""/usr/local/lib/python2.7/dist-packages/trac/web/main.py"", line 554, in _dispatch_request
    dispatcher.dispatch(req)
  File ""/usr/local/lib/python2.7/dist-packages/trac/web/main.py"", line 247, in dispatch
    resp = chosen_handler.process_request(req)
  File ""/usr/local/lib/python2.7/dist-packages/trac/versioncontrol/web_ui/changeset.py"", line 353, in process_request
    self._render_html(req, repos, chgset, restricted, xhr, data)
  File ""/usr/local/lib/python2.7/dist-packages/trac/versioncontrol/web_ui/changeset.py"", line 588, in _render_html
    diff_bytes += _estimate_changes(old_node, new_node)
  File ""/usr/local/lib/python2.7/dist-packages/trac/versioncontrol/web_ui/changeset.py"", line 538, in _estimate_changes
    return old_size + new_size
TypeError: unsupported operand type(s) for +: 'NoneType' and 'NoneType'
}}}"	defect	closed	high	never	*unknown*		invalid