add subqueries tests

Author: timgraham

django_mongodb_backend/compiler.py

@@ -53,7 +53,7 @@ def _get_column_from_expression(self, expr, alias):
         Create a column named `alias` from the given expression to hold the
         aggregate value.
         """
-        column_target = expr.output_field.__class__()
+        column_target = expr.output_field.clone()
         column_target.db_column = alias
         column_target.set_attributes_from_name(alias)
         return Col(self.collection_name, column_target)
@@ -81,7 +81,7 @@ def _prepare_expressions_for_pipeline(self, expression, target, annotation_group
             alias = (
                 f"__aggregation{next(annotation_group_idx)}" if sub_expr != expression else target
             )
-            column_target = sub_expr.output_field.__class__()
+            column_target = sub_expr.output_field.clone()
             column_target.db_column = alias
             column_target.set_attributes_from_name(alias)
             inner_column = Col(self.collection_name, column_target)

tests/model_fields_/models.py

@@ -119,3 +119,10 @@ class Author(models.Model):
 class Book(models.Model):
     name = models.CharField(max_length=100)
     author = EmbeddedModelField(Author)
+
+
+class Library(models.Model):
+    name = models.CharField(max_length=100)
+    books = models.ManyToManyField("Book", related_name="libraries")
+    location = models.CharField(max_length=100, null=True, blank=True)
+    best_seller = models.CharField(max_length=100, null=True, blank=True)

tests/model_fields_/test_embedded_model.py

@@ -1,5 +1,10 @@
 from django.core.exceptions import ValidationError
 from django.db import models
+from django.db.models import (
+    Exists,
+    OuterRef,
+    Subquery,
+)
 from django.test import SimpleTestCase, TestCase
 from django.test.utils import isolate_apps
 
@@ -11,6 +16,7 @@
     Book,
     Data,
     Holder,
+    Library,
 )
 
 
@@ -123,3 +129,62 @@ class MyModel(models.Model):
         self.assertEqual(
             msg, "Embedded models cannot have relational fields (Target.key is a ForeignKey)."
         )
+
+
+class SubqueryExistsTest(TestCase):
+    def setUp(self):
+        # Create test data
+        address1 = Address.objects.create(city="New York", state="NY", zip_code=10001)
+        address2 = Address.objects.create(city="Boston", state="MA", zip_code=20002)
+        author1 = Author.objects.create(name="Alice", age=30, address=address1)
+        author2 = Author.objects.create(name="Bob", age=40, address=address2)
+        book1 = Book.objects.create(name="Book A", author=author1)
+        book2 = Book.objects.create(name="Book B", author=author2)
+        Book.objects.create(name="Book C", author=author2)
+        Book.objects.create(name="Book D", author=author2)
+        Book.objects.create(name="Book E", author=author1)
+
+        library1 = Library.objects.create(
+            name="Central Library", location="Downtown", best_seller="Book A"
+        )
+        library2 = Library.objects.create(
+            name="Community Library", location="Suburbs", best_seller="Book A"
+        )
+
+        # Add books to libraries
+        library1.books.add(book1, book2)
+        library2.books.add(book2)
+
+    def test_exists_subquery(self):
+        subquery = Book.objects.filter(
+            author__name=OuterRef("name"), author__address__city="Boston"
+        )
+        queryset = Author.objects.filter(Exists(subquery))
+
+        self.assertEqual(queryset.count(), 1)
+
+    def test_in_subquery(self):
+        subquery = Author.objects.filter(age__gt=35).values("name")
+        queryset = Book.objects.filter(author__name__in=Subquery(subquery)).order_by("name")
+
+        self.assertEqual(queryset.count(), 3)
+        self.assertQuerySetEqual(queryset, ["Book B", "Book C", "Book D"], lambda book: book.name)
+
+    def test_range_query(self):
+        queryset = Author.objects.filter(age__range=(25, 45)).order_by("name")
+
+        self.assertEqual(queryset.count(), 2)
+        self.assertQuerySetEqual(queryset, ["Alice", "Bob"], lambda author: author.name)
+
+    def test_exists_with_foreign_object(self):
+        subquery = Library.objects.filter(best_seller=OuterRef("name"))
+        queryset = Book.objects.filter(Exists(subquery))
+
+        self.assertEqual(queryset.count(), 1)
+        self.assertEqual(queryset.first().name, "Book A")
+
+    def test_foreign_field_with_ranges(self):
+        queryset = Library.objects.filter(books__author__age__range=(25, 35))
+
+        self.assertEqual(queryset.count(), 1)
+        self.assertEqual(queryset.first().name, "Central Library")