Since upgrading to OSX 10.9 I seem to have this issue when running trial (tried it with Twisted 13.0.0, 13.2.0 and 14.0.0):

Unexpected error while writing cache file
Traceback (most recent call last):
  File "/usr/local/lib/python2.7/site-packages/twisted/scripts/trial.py", line 472, in postOptions
    _BasicOptions.postOptions(self)
  File "/usr/local/lib/python2.7/site-packages/twisted/scripts/trial.py", line 382, in postOptions
    self['reporter'] = self._loadReporterByName(self['reporter'])
  File "/usr/local/lib/python2.7/site-packages/twisted/scripts/trial.py", line 369, in _loadReporterByName
    for p in plugin.getPlugins(itrial.IReporter):
  File "/usr/local/lib/python2.7/site-packages/twisted/plugin.py", line 209, in getPlugins
    allDropins = getCache(package)
--- <exception caught here> ---
  File "/usr/local/lib/python2.7/site-packages/twisted/plugin.py", line 181, in getCache
    dropinPath.setContent(pickle.dumps(dropinDotCache))

The only zip on the path is the pseudo python27.zip.

Any ideas?

-J