Parsing a date in python without using a default

Question

I\'m using python\'s dateutil.parser tool to parse some dates I\'m getting from a third party feed. It allows specifying a default date, which itself defaults

Answer 1

This is probably a "hack", but it looks like dateutil looks at very few attributes out of the default you pass in. You could provide a 'fake' datetime that explodes in the desired way.

>>> import datetime
>>> import dateutil.parser
>>> class NoDefaultDate(object):
...     def replace(self, **fields):
...         if any(f not in fields for f in ('year', 'month', 'day')):
...             return None
...         return datetime.datetime(2000, 1, 1).replace(**fields)
>>> def wrap_parse(v):
...     _actual = dateutil.parser.parse(v, default=NoDefaultDate())
...     return _actual.date() if _actual is not None else None
>>> cases = (
...   ('2011-10-12', datetime.date(2011, 10, 12)),
...   ('2011-10', None),
...   ('2011', None),
...   ('10-12', None),
...   ('2011-10-12T11:45:30', datetime.date(2011, 10, 12)),
...   ('10-12 11:45', None),
...   ('', None),
...   )
>>> all(wrap_parse(test) == expected for test, expected in cases)
True