TypeError: unsupported operand type(s) for -: 'int' and 'NoneType'

[stromnov@…]

How to Reproduce

While doing a GET operation on /wiki/WikiStart, Trac issued an internal error.

System Information

Python	2.4.3 (#2, Oct 18 2006, 08:31:46) [GCC 3.4.4 [FreeBSD] 20050518]
Subversion	1.4.0
SQLite	3.3.7
pysqlite	2.3.2

Python Traceback

Traceback (most recent call last):
  File "/usr/local/lib/python2.4/site-packages/trac/web/main.py", line 377, in dispatch_request
    dispatcher.dispatch(req)
  File "/usr/local/lib/python2.4/site-packages/trac/web/main.py", line 248, in dispatch
    content_type)
  File "/usr/local/lib/python2.4/site-packages/trac/web/chrome.py", line 471, in render_template
    return stream.render(method, doctype=doctype)

  ...some traceback stripped off...

  File "/usr/local/lib/python2.4/site-packages/genshi/template.py", line 929, in _eval
    result = data.evaluate(ctxt)
  File "/usr/local/lib/python2.4/site-packages/genshi/eval.py", line 103, in evaluate
    {'data': data})
  File "/usr/local/share/trac/templates/wiki_diff.html", line 73, in <Expression u"new_version - old_version > 1 and "version %d to " % (old_version+1) or """>
    <input type="submit" name="delete_version" value="Delete ${
TypeError: unsupported operand type(s) for -: 'int' and 'NoneType'

[Christian Boos]

Ok, this is triggered when trying to view the Last change of a newly created page.

[Christian Boos]

Should be fixed by r4023.