Infinite recursion upon rendering repository files

[strk@…]

After upgrading from 1.0 to 1.2 (r15395), attempts to read *any* file from the Browse Source tree result in an infinite recursion, eventually handled by a Maximum recursion depth exceeded while calling a Python object error.

The backtrace:

...
  File "/usr/local/lib/python2.6/dist-packages/Trac-1.2.1dev-py2.6.egg/trac/util/__init__.py", line 1197, in __get__
    result = self.fn(instance)
  File "/usr/local/lib/python2.6/dist-packages/Trac-1.2.1dev-py2.6.egg/trac/mimeview/pygments.py", line 241, in _types
    js_entry = self._types.get('text/javascript')
  File "/usr/local/lib/python2.6/dist-packages/Trac-1.2.1dev-py2.6.egg/trac/util/__init__.py", line 1197, in __get__
    result = self.fn(instance)
  File "/usr/local/lib/python2.6/dist-packages/Trac-1.2.1dev-py2.6.egg/trac/mimeview/pygments.py", line 241, in _types
    js_entry = self._types.get('text/javascript')
...

I've also reported this on the user list: ​https://groups.google.com/forum/#!topic/trac-users/yaMesS3G6uo

[strk@…]

Uninstalling package-manager installed python-pygments (Pygments==1.3.1) fixed the issue. It looks like the package was shadowing a newer Pygments==2.2.0

Not sure if Trac could/should handle this case (broken dep?) itself.

[Jun Omae]

Thanks for the reporting. PygmentsRenderer._types method decorated with @lazy recursively use self._types property at tags/trac-1.2/trac/mimeview/pygments.py@:231-232,241#L231​.

It seems this issue introduced in [14208].

[Jun Omae]

It can be reproduced with Pygments 1.3.

[Ryan J Ollos]

It looks like a simple fix would be:

trac/mimeview/pygments.py

@@ -238 +238 @@
 
         # Pygments < 1.4 doesn't know application/javascript
         if 'application/javascript' not in types:
-            js_entry = self._types.get('text/javascript')
+            js_entry = types.get('text/javascript')
             if js_entry:
                 types['application/javascript'] = js_entry
 

[Ryan J Ollos]

Committed to 1.2-stable in r15488, merged to trunk in r15489.