Fixed #28293 -- Fixed union(), intersection(), and difference() when combining with an EmptyQuerySet.

Thanks Jon Dufresne for the report and Tim Graham for the review.
This commit is contained in:
Mariusz Felisiak 2017-06-13 08:16:16 +02:00 committed by GitHub
parent 9dc83c356d
commit 82175ead72
4 changed files with 42 additions and 1 deletions

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@ -818,12 +818,25 @@ class QuerySet:
return clone
def union(self, *other_qs, all=False):
# If the query is an EmptyQuerySet, combine all nonempty querysets.
if isinstance(self, EmptyQuerySet):
qs = [q for q in other_qs if not isinstance(q, EmptyQuerySet)]
return qs[0]._combinator_query('union', *qs[1:], all=all) if qs else self
return self._combinator_query('union', *other_qs, all=all)
def intersection(self, *other_qs):
# If any query is an EmptyQuerySet, return it.
if isinstance(self, EmptyQuerySet):
return self
for other in other_qs:
if isinstance(other, EmptyQuerySet):
return other
return self._combinator_query('intersection', *other_qs)
def difference(self, *other_qs):
# If the query is an EmptyQuerySet, return it.
if isinstance(self, EmptyQuerySet):
return self
return self._combinator_query('difference', *other_qs)
def select_for_update(self, nowait=False, skip_locked=False):

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@ -390,7 +390,7 @@ class SQLCompiler:
features = self.connection.features
compilers = [
query.get_compiler(self.using, self.connection)
for query in self.query.combined_queries
for query in self.query.combined_queries if not query.is_empty()
]
if not features.supports_slicing_ordering_in_compound:
for query, compiler in zip(self.query.combined_queries, compilers):

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@ -29,3 +29,6 @@ Bugfixes
* Fixed crash in admin's inlines when a model has an inherited non-editable
primary key (:ticket:`27967`).
* Fixed ``QuerySet.union()``, ``intersection()``, and ``difference()`` when
combining with an ``EmptyQuerySet`` (:ticket:`28293`).

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@ -42,6 +42,31 @@ class QuerySetSetOperationTests(TestCase):
self.assertEqual(len(list(qs1.union(qs2, all=True))), 20)
self.assertEqual(len(list(qs1.union(qs2))), 10)
@skipUnlessDBFeature('supports_select_intersection')
def test_intersection_with_empty_qs(self):
qs1 = Number.objects.all()
qs2 = Number.objects.none()
self.assertEqual(len(qs1.intersection(qs2)), 0)
self.assertEqual(len(qs2.intersection(qs1)), 0)
self.assertEqual(len(qs2.intersection(qs2)), 0)
@skipUnlessDBFeature('supports_select_difference')
def test_difference_with_empty_qs(self):
qs1 = Number.objects.all()
qs2 = Number.objects.none()
self.assertEqual(len(qs1.difference(qs2)), 10)
self.assertEqual(len(qs2.difference(qs1)), 0)
self.assertEqual(len(qs2.difference(qs2)), 0)
def test_union_with_empty_qs(self):
qs1 = Number.objects.all()
qs2 = Number.objects.none()
self.assertEqual(len(qs1.union(qs2)), 10)
self.assertEqual(len(qs2.union(qs1)), 10)
self.assertEqual(len(qs2.union(qs1, qs1, qs1)), 10)
self.assertEqual(len(qs2.union(qs1, qs1, all=True)), 20)
self.assertEqual(len(qs2.union(qs2)), 0)
def test_limits(self):
qs1 = Number.objects.all()
qs2 = Number.objects.all()