Fixed #25307 -- Fixed QuerySet.annotate() crash with conditional expressions.

Thanks Travis Newport for the tests and Josh Smeaton for contributing
to the patch.
This commit is contained in:
Josh Smeaton 2017-01-17 02:03:15 +11:00 committed by Tim Graham
parent f2d2f17896
commit 1df89a60c5
4 changed files with 84 additions and 2 deletions

View File

@ -56,6 +56,17 @@ class Lookup(object):
sqls, sqls_params = ['%s'] * len(params), params
return sqls, sqls_params
def get_source_expressions(self):
if self.rhs_is_direct_value():
return [self.lhs]
return [self.lhs, self.rhs]
def set_source_expressions(self, new_exprs):
if len(new_exprs) == 1:
self.lhs = new_exprs[0]
else:
self.lhs, self.rhs = new_exprs
def get_prep_lookup(self):
if hasattr(self.rhs, '_prepare'):
return self.rhs._prepare(self.lhs.output_field)
@ -116,6 +127,10 @@ class Lookup(object):
def contains_aggregate(self):
return self.lhs.contains_aggregate or getattr(self.rhs, 'contains_aggregate', False)
@property
def is_summary(self):
return self.lhs.is_summary or getattr(self.rhs, 'is_summary', False)
class Transform(RegisterLookupMixin, Func):
"""

View File

@ -18,6 +18,7 @@ from django.db.models.aggregates import Count
from django.db.models.constants import LOOKUP_SEP
from django.db.models.expressions import Col, Ref
from django.db.models.fields.related_lookups import MultiColSource
from django.db.models.lookups import Lookup
from django.db.models.query_utils import (
Q, check_rel_lookup_compatibility, refs_expression,
)
@ -366,11 +367,20 @@ class Query(object):
orig_exprs = annotation.get_source_expressions()
new_exprs = []
for expr in orig_exprs:
# FIXME: These conditions are fairly arbitrary. Identify a better
# method of having expressions decide which code path they should
# take.
if isinstance(expr, Ref):
# Its already a Ref to subquery (see resolve_ref() for
# details)
new_exprs.append(expr)
elif isinstance(expr, Col):
elif isinstance(expr, (WhereNode, Lookup)):
# Decompose the subexpressions further. The code here is
# copied from the else clause, but this condition must appear
# before the contains_aggregate/is_summary condition below.
new_expr, col_cnt = self.rewrite_cols(expr, col_cnt)
new_exprs.append(new_expr)
elif isinstance(expr, Col) or (expr.contains_aggregate and not expr.is_summary):
# Reference to column. Make sure the referenced column
# is selected.
col_cnt += 1

View File

@ -118,6 +118,13 @@ class WhereNode(tree.Node):
cols.extend(child.get_group_by_cols())
return cols
def get_source_expressions(self):
return self.children[:]
def set_source_expressions(self, children):
assert len(children) == len(self.children)
self.children = children
def relabel_aliases(self, change_map):
"""
Relabels the alias values of any children. 'change_map' is a dictionary
@ -160,6 +167,10 @@ class WhereNode(tree.Node):
def contains_aggregate(self):
return self._contains_aggregate(self)
@property
def is_summary(self):
return any(child.is_summary for child in self.children)
class NothingNode(object):
"""

View File

@ -9,7 +9,8 @@ from django.contrib.contenttypes.models import ContentType
from django.core.exceptions import FieldError
from django.db import connection
from django.db.models import (
Avg, Count, F, Max, Q, StdDev, Sum, Value, Variance,
Avg, Case, Count, DecimalField, F, IntegerField, Max, Q, StdDev, Sum,
Value, Variance, When,
)
from django.test import TestCase, skipUnlessAnyDBFeature, skipUnlessDBFeature
from django.test.utils import Approximate
@ -371,6 +372,51 @@ class AggregationTests(TestCase):
{'c__max': 3}
)
def test_conditional_aggreate(self):
# Conditional aggregation of a grouped queryset.
self.assertEqual(
Book.objects.annotate(c=Count('authors')).values('pk').aggregate(test=Sum(
Case(When(c__gt=1, then=1), output_field=IntegerField())
))['test'],
3
)
def test_sliced_conditional_aggregate(self):
self.assertEqual(
Author.objects.all()[:5].aggregate(test=Sum(Case(
When(age__lte=35, then=1), output_field=IntegerField()
)))['test'],
3
)
def test_annotated_conditional_aggregate(self):
annotated_qs = Book.objects.annotate(discount_price=F('price') * 0.75)
self.assertAlmostEqual(
annotated_qs.aggregate(test=Avg(Case(
When(pages__lt=400, then='discount_price'),
output_field=DecimalField()
)))['test'],
22.27, places=2
)
def test_distinct_conditional_aggregate(self):
self.assertEqual(
Book.objects.distinct().aggregate(test=Avg(Case(
When(price=Decimal('29.69'), then='pages'),
output_field=IntegerField()
)))['test'],
325
)
def test_conditional_aggregate_on_complex_condition(self):
self.assertEqual(
Book.objects.distinct().aggregate(test=Avg(Case(
When(Q(price__gte=Decimal('29')) & Q(price__lt=Decimal('30')), then='pages'),
output_field=IntegerField()
)))['test'],
325
)
def test_decimal_aggregate_annotation_filter(self):
"""
Filtering on an aggregate annotation with Decimal values should work.