Uninstall virtualenv, Mac When trying to run a command:

pip uninstall virtualenv


it raises an error:

Exception:
Traceback (most recent call last):
  File "/usr/local/Cellar/python/2.7.8_1/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pip-1.5.6-py2.7.egg/pip/basecommand.py", line 122, in main
    status = self.run(options, args)
  File "/usr/local/Cellar/python/2.7.8_1/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pip-1.5.6-py2.7.egg/pip/commands/uninstall.py", line 59, in run
    requirement_set.uninstall(auto_confirm=options.yes)
  File "/usr/local/Cellar/python/2.7.8_1/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pip-1.5.6-py2.7.egg/pip/req.py", line 1035, in uninstall
    req.uninstall(auto_confirm=auto_confirm)
  File "/usr/local/Cellar/python/2.7.8_1/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pip-1.5.6-py2.7.egg/pip/req.py", line 568, in uninstall
    for path in pip.wheel.uninstallation_paths(dist):
  File "/usr/local/Cellar/python/2.7.8_1/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pip-1.5.6-py2.7.egg/pip/wheel.py", line 375, in unique
    for item in fn(*args, **kw):
  File "/usr/local/Cellar/python/2.7.8_1/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pip-1.5.6-py2.7.egg/pip/wheel.py", line 393, in uninstallation_paths
    r = csv.reader(FakeFile(dist.get_metadata_lines('RECORD')))
  File "/usr/local/Cellar/python/2.7.8_1/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pip-1.5.6-py2.7.egg/pip/_vendor/pkg_resources.py", line 1369, in get_metadata_lines
    return yield_lines(self.get_metadata(name))
  File "/usr/local/Cellar/python/2.7.8_1/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pip-1.5.6-py2.7.egg/pip/_vendor/pkg_resources.py", line 1361, in get_metadata
    return self._get(self._fn(self.egg_info,name))
  File "/usr/local/Cellar/python/2.7.8_1/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/pip-1.5.6-py2.7.egg/pip/_vendor/pkg_resources.py", line 1470, in _get
    stream = open(path, 'rb')
IOError: [Errno 2] No such file or directory: '/Library/Python/2.7/site-packages/virtualenv-1.11.6.dist-info/RECORD'

Storing debug log for failure in /var/folders/qn/_rqylh917b33tgzrfm1wy79h0000gn/T/tmpFtrtEX


I have no clue how to fix it, it start to show when I was trying to uninstall packages. Does anyone know how to solve the issue?
I encountered the same problem. I solved it by creating an empty file called RECORD in the virtualenv directory. 

On my machine, the command to run in Terminal was 

 touch /usr/local/lib/python2.7/site-packages/virtualenv-1.11.6.dist-info/RECORD


That's it. After doing that, pip install virtualenv --upgrade worked for me.