[TIP] dicts in doctests

[Nicolas Chauvat]

On Wed, Sep 17, 2008 at 07:43:43PM -0500, Pete wrote:
> Hiya-
> 
> Is there a preferred way of testing dicts in doctests?  The random key  
> ordering can be problematic (IIRC, this bit the django port to Jython).
> 
>  >>> dict([('x', 1), ('y', 2)])
> {'x': 1, 'y': 2}
> 
> Python doesn't guarantee what order the dict is printed in.  It'd be  
> possible to work around like so:
> 
>  >>> dict([('x', 1), ('y', 2)]) == {'x': 1, 'y': 2}
> True
> 
> or even
> 
>  >>> d = dict([('x', 1), ('y', 2)])
>  >>> sorted(d.items())
> [('x': 1), ('y': 2)]
> 
> But both of these approaches kinda defeat the tests as documentation  
> benefit.
> 
> Any thoughts?  Just go with the first case & hope for the best?  The  
> ordering's relatively stable across CPythons (versions & platforms)  
> AFAIK...

from logilab.common.testlib import TestCase

class MyTestCase(TestCase):

      def test_me(self):
          self.assertDictEquals({1:'one'}, {2:'two'})

will provide a nice error message if the assertion fails.

-- 
Nicolas Chauvat

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