ENH/BUG: pass formatting params thru to to_csv

[patricktokeeffe]

Add support for passing remaining csv.writer formatting parameters thru to DataFrame.to_csv().

Maybe write tests for this? That much is over my head currently.

[jtratner]

Can't just add this...needs to be supported by C parser too (and therefore needs tests, etc)

[patricktokeeffe]

Yea, I didn't expect it to be that easy. Is it better etiquette to close this PR and reopen later or just leave it hanging?

[jtratner]

oh this is to_csv -- just need to put together some tests for this.

[jreback]

does this close an issue?

need tests for this

[patricktokeeffe]

I realized this commit was doing two things so I refactored into a separate PR (#6034). I'm still a little lost on what kind of test to make though since these params are just passed internally to com.UnicodeWriter or csv.writer.

The only thing that occurs to me is to write an output file using the new parameters then read it back in and make sure the write occurred correctly. Is that overkill? Any tips or hints what to model the test(s) on?

[patricktokeeffe]

This PR seems to cover #4528 too

[patricktokeeffe]

I tried using self.assertRaises as a context manager which doesn't work for python2.6. Any tips on compatibility?

[patricktokeeffe]

Specifically it fails like this:

Traceback (most recent call last):
  File "/home/travis/virtualenv/python2.6_with_system_site_packages/lib/python2.6/site-packages/pandas/tests/test_format.py", line 1729, in test_to_csv_quotechar
    df.to_csv(path, quoting=1, quotechar=None)
  File "/usr/lib/python2.6/contextlib.py", line 34, in __exit__
    self.gen.throw(type, value, traceback)
  File "/home/travis/virtualenv/python2.6_with_system_site_packages/lib/python2.6/site-packages/pandas/util/testing.py", line 372, in ensure_clean
    yield filename
  File "/home/travis/virtualenv/python2.6_with_system_site_packages/lib/python2.6/site-packages/pandas/tests/test_format.py", line 1728, in test_to_csv_quotechar
    with self.assertRaises(TypeError):
TypeError: failUnlessRaises() takes at least 3 arguments (2 given)

[TomAugspurger]

Use with tm.assertRaises(TypeError):

https://github.com/pydata/pandas/wiki/Testing#wiki-testing-for-exceptions

[patricktokeeffe]

Thanks @TomAugspurger

[jreback]

@patricktokeeffe pls rebase, and move the release notes to 0.14 section. thanks

which issues does this cover?

[patricktokeeffe]

@jreback I sent this PR without creating an issue. It does cover #4528 though the idea mentioned there of adding a csv dialect argument is a good one not included in this PR.

[jreback]

thanks nice little fix!