Fixed bug with QuerySet.exclude() failing to do negations on Q objects, and

at the same time generalised exclude/QNot so that they work for 'external'
Q objects i.e. ones that simply have 'get_sql' defined.


git-svn-id: http://code.djangoproject.com/svn/django/trunk@2997 bcc190cf-cafb-0310-a4f2-bffc1f526a37
This commit is contained in:
Luke Plant 2006-05-26 23:41:43 +00:00
parent c3baf4668f
commit 60c3e55b1f
2 changed files with 17 additions and 6 deletions

View File

@ -291,22 +291,26 @@ class QuerySet(object):
def filter(self, *args, **kwargs):
"Returns a new QuerySet instance with the args ANDed to the existing set."
return self._filter_or_exclude(Q, *args, **kwargs)
return self._filter_or_exclude(None, *args, **kwargs)
def exclude(self, *args, **kwargs):
"Returns a new QuerySet instance with NOT (args) ANDed to the existing set."
return self._filter_or_exclude(QNot, *args, **kwargs)
def _filter_or_exclude(self, qtype, *args, **kwargs):
def _filter_or_exclude(self, mapper, *args, **kwargs):
# mapper is a callable used to transform Q objects,
# or None for identity transform
if mapper is None:
mapper = lambda x: x
if len(args) > 0 or len(kwargs) > 0:
assert self._limit is None and self._offset is None, \
"Cannot filter a query once a slice has been taken."
clone = self._clone()
if len(kwargs) > 0:
clone._filters = clone._filters & qtype(**kwargs)
clone._filters = clone._filters & mapper(Q(**kwargs))
if len(args) > 0:
clone._filters = clone._filters & reduce(operator.and_, args)
clone._filters = clone._filters & reduce(operator.and_, map(mapper, args))
return clone
def complex_filter(self, filter_obj):
@ -318,7 +322,7 @@ class QuerySet(object):
if hasattr(filter_obj, 'get_sql'):
return self._filter_or_exclude(None, filter_obj)
else:
return self._filter_or_exclude(Q, **filter_obj)
return self._filter_or_exclude(None, **filter_obj)
def select_related(self, true_or_false=True):
"Returns a new QuerySet instance with '_select_related' modified."
@ -582,9 +586,12 @@ class Q(object):
class QNot(Q):
"Encapsulates NOT (...) queries as objects"
def __init__(self, q):
"Creates a negation of the q object passed in."
self.q = q
def get_sql(self, opts):
tables, joins, where, params = super(QNot, self).get_sql(opts)
tables, joins, where, params = self.q.get_sql(opts)
where2 = ['(NOT (%s))' % " AND ".join(where)]
return tables, joins, where2, params

View File

@ -89,6 +89,10 @@ Hello and goodbye
>>> Article.objects.filter(Q(headline__startswith='Hello')).in_bulk([1,2])
{1: Hello}
# Demonstrating exclude with a Q object
>>> Article.objects.exclude(Q(headline__startswith='Hello'))
[Goodbye]
# The 'complex_filter' method supports framework features such as
# 'limit_choices_to' which normally take a single dictionary of lookup arguments
# but need to support arbitrary queries via Q objects too.