pyclaw.io name collision with python's io module when running doctest

[ketch]

Attempting to run doctests in src/pyclaw gives

» python geometry.py
Traceback (most recent call last):
  File "geometry.py", line 771, in <module>
    import doctest
  File "/Users/ketch/anaconda/lib/python2.7/doctest.py", line 99, in <module>
    import unittest, difflib, pdb, tempfile
  File "/Users/ketch/anaconda/lib/python2.7/tempfile.py", line 32, in <module>
    import io as _io
  File "/Users/ketch/Research/Software/clawpack/pyclaw/src/pyclaw/io/__init__.py", line 14, in <module>
    import ascii 
  File "/Users/ketch/Research/Software/clawpack/pyclaw/src/pyclaw/io/ascii.py", line 12, in <module>
    from ..util import read_data_line
ValueError: Attempted relative import beyond toplevel package

I was initially misled by the message about the relative import. The thing is, pyclaw.io shouldn't be involved at all here (this is the geometry module!) Doctest is trying to import the basic python IO module but it picks up the local package called "io" first.

Namespace fail.

This is extremely annoying. One option is to rename our io module, but that seems silly.

[mandli]

Running nosetests in src/pyclaw

nosetests --first-pkg-wins --with-doctest --exclude=example

seems to avoid this issue.

[mandli]

Should we add this to the travis script then?

[ketch]

I did, here: #405
But there are other issues, which I'm working on.

https://twitter.com/steve_silvester/status/519632438159372288

[ketch]

I'm going to close this since @mandli's workaround seems like the best option.