Handle .filter_is_sticky (#17)

include/expressions.py

@@ -174,6 +174,8 @@ def add_where(self, queryset, host_table, included_table):
 
 
 class IncludeExpression(Expression):
+    # No need to use group bys when using .include
+    contains_aggregate = False
 
     def __init__(self, field, children=None):
         expressions = []

include/query.py

@@ -99,6 +99,13 @@ def include(self, *fields, **kwargs):
         """
         clone = self._clone()
 
+        # Preserve the stickiness of related querysets
+        # NOTE: by default _clone will clear this attribute
+        # .include does not modify the actual query, so we
+        # should not clear `filter_is_sticky`
+        if self.query.filter_is_sticky:
+            clone.query.filter_is_sticky = True
+
         clone._include_limit = kwargs.pop('limit_includes', None)
         assert not kwargs, '"limit_includes" is the only accepted kwargs. Eat your heart out 2.7'
 
@@ -111,15 +118,15 @@ def include(self, *fields, **kwargs):
         # Including multiple child fields ie .include(field1__field2, field1__field3)
         # turns into {field1: {field2: {}, field3: {}}
         for name in fields:
-            ctx, model = self._includes, self.model
+            ctx, model = clone._includes, clone.model
             for spl in name.split('__'):
                 field = model._meta.get_field(spl)
                 if isinstance(field, ForeignObjectRel) and field.is_hidden():
                     raise ValueError('Hidden field "{!r}" has no descriptor and therefore cannot be included'.format(field))
                 model = field.related_model
                 ctx = ctx.setdefault(field, OrderedDict())
 
-        for field in self._includes.keys():
+        for field in clone._includes.keys():
             clone._include(field)
 
         return clone
@@ -131,7 +138,11 @@ def count(self):
 
     def _clone(self):
         clone = super(IncludeQuerySet, self)._clone()
-        clone._includes = self._includes
+
+        clone._includes = self._includes.copy()
+        for field in self._includes.keys():
+            clone._include(field)
+
         return clone
 
     def _include(self, field):

tests/migrations/0003_auto_20170825_1341.py

@@ -0,0 +1,43 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.11.4 on 2017-08-25 13:41
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('tests', '0002_auto_20170713_1713'),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='Membership',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('active', models.BooleanField(default=True)),
+                ('joined', models.DateTimeField(auto_now_add=True)),
+                ('member', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='memberships', to='tests.Cat')),
+            ],
+        ),
+        migrations.CreateModel(
+            name='Organization',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('title', models.CharField(max_length=75)),
+                ('disliked', models.BooleanField(default=True)),
+            ],
+        ),
+        migrations.AddField(
+            model_name='membership',
+            name='organization',
+            field=models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='members', to='tests.Organization'),
+        ),
+        migrations.AddField(
+            model_name='cat',
+            name='organizations',
+            field=models.ManyToManyField(through='tests.Membership', to='tests.Organization'),
+        ),
+    ]

tests/models.py

@@ -31,5 +31,23 @@ class Cat(models.Model):
     parent = models.ForeignKey('Cat', null=True, related_name='children')
     siblings = models.ManyToManyField('Cat', related_name='related_to')
     emergency_contact = models.OneToOneField('Cat', null=True, related_name='emergency_contact_for')
+    organizations = models.ManyToManyField('Organization', through='Membership')
+
+    objects = IncludeManager()
+
+
+class Organization(models.Model):
+    title = models.CharField(max_length=75)
+    disliked = models.BooleanField(default=True)
+
+    objects = IncludeManager()
+
+
+class Membership(models.Model):
+    active = models.BooleanField(default=True)
+    joined = models.DateTimeField(auto_now_add=True)
+
+    organization = models.ForeignKey(Organization, related_name='members')
+    member = models.ForeignKey(Cat, related_name='memberships')
 
     objects = IncludeManager()

tests/test_include.py

@@ -275,3 +275,11 @@ def test_reverse_gfk(self, django_assert_num_queries):
         with django_assert_num_queries(1):
             ket = models.Cat.objects.include('aliases').get(pk=cat.id)
             assert len(ket.aliases.all()) == 7
+
+    def test_chaining(self, django_assert_num_queries):
+        cat = factories.CatFactory()
+
+        qs1 = cat.organizations.all().filter(members__active=False).include('members')
+        qs2 = cat.organizations.all().include('members').filter(members__active=False)
+
+        assert str(qs1.query) == str(qs2.query)