expose querysetproxy on reverse of foreignkey (virtual fk), add additional methods from queryset to querysetproxy

tests/test_queryproxy_on_m2m_models.py

@@ -0,0 +1,182 @@
+import asyncio
+from typing import List, Optional, Union
+
+import databases
+import pytest
+import sqlalchemy
+
+import ormar
+from tests.settings import DATABASE_URL
+
+database = databases.Database(DATABASE_URL, force_rollback=True)
+metadata = sqlalchemy.MetaData()
+
+
+class Subject(ormar.Model):
+    class Meta:
+        tablename = "subjects"
+        database = database
+        metadata = metadata
+
+    id: int = ormar.Integer(primary_key=True)
+    name: str = ormar.String(max_length=80)
+
+
+class Author(ormar.Model):
+    class Meta:
+        tablename = "authors"
+        database = database
+        metadata = metadata
+
+    id: int = ormar.Integer(primary_key=True)
+    first_name: str = ormar.String(max_length=80)
+    last_name: str = ormar.String(max_length=80)
+
+
+class Category(ormar.Model):
+    class Meta:
+        tablename = "categories"
+        database = database
+        metadata = metadata
+
+    id: int = ormar.Integer(primary_key=True)
+    name: str = ormar.String(max_length=40)
+    sort_order: int = ormar.Integer(nullable=True)
+    subject: Optional[Subject] = ormar.ForeignKey(Subject)
+
+
+class PostCategory(ormar.Model):
+    class Meta:
+        tablename = "posts_categories"
+        database = database
+        metadata = metadata
+
+
+class Post(ormar.Model):
+    class Meta:
+        tablename = "posts"
+        database = database
+        metadata = metadata
+
+    id: int = ormar.Integer(primary_key=True)
+    title: str = ormar.String(max_length=200)
+    categories: Optional[Union[Category, List[Category]]] = ormar.ManyToMany(
+        Category, through=PostCategory
+    )
+    author: Optional[Author] = ormar.ForeignKey(Author)
+
+
+@pytest.fixture(scope="module")
+def event_loop():
+    loop = asyncio.get_event_loop()
+    yield loop
+    loop.close()
+
+
+@pytest.fixture(autouse=True, scope="module")
+async def create_test_database():
+    engine = sqlalchemy.create_engine(DATABASE_URL)
+    metadata.create_all(engine)
+    yield
+    metadata.drop_all(engine)
+
+
+@pytest.mark.asyncio
+async def test_queryset_methods():
+    async with database:
+        async with database.transaction(force_rollback=True):
+            guido = await Author.objects.create(
+                first_name="Guido", last_name="Van Rossum"
+            )
+            subject = await Subject(name="Random").save()
+            post = await Post.objects.create(title="Hello, M2M", author=guido)
+            news = await Category.objects.create(
+                name="News", sort_order=1, subject=subject
+            )
+            breaking = await Category.objects.create(
+                name="Breaking", sort_order=3, subject=subject
+            )
+
+            # Add a category to a post.
+            await post.categories.add(news)
+            await post.categories.add(breaking)
+
+            category = await post.categories.get_or_create(name="News")
+            assert category == news
+            assert len(post.categories) == 1
+
+            category = await post.categories.get_or_create(name="Breaking News")
+            assert category != breaking
+            assert category.pk is not None
+            assert len(post.categories) == 2
+
+            await post.categories.update_or_create(pk=category.pk, name="Urgent News")
+            assert len(post.categories) == 2
+            cat = await post.categories.get_or_create(name="Urgent News")
+            assert cat.pk == category.pk
+            assert len(post.categories) == 1
+
+            await post.categories.remove(cat)
+            await cat.delete()
+
+            assert len(post.categories) == 0
+
+            category = await post.categories.update_or_create(
+                name="Weather News", sort_order=2, subject=subject
+            )
+            assert category.pk is not None
+            assert category.posts[0] == post
+
+            assert len(post.categories) == 1
+
+            categories = await post.categories.all()
+            assert len(categories) == 3 == len(post.categories)
+
+            assert await post.categories.exists()
+            assert 3 == await post.categories.count()
+
+            categories = await post.categories.limit(2).all()
+            assert len(categories) == 2 == len(post.categories)
+
+            categories2 = await post.categories.limit(2).offset(1).all()
+            assert len(categories2) == 2 == len(post.categories)
+            assert categories != categories2
+
+            categories = await post.categories.order_by("-sort_order").all()
+            assert len(categories) == 3 == len(post.categories)
+            assert post.categories[2].name == "News"
+            assert post.categories[0].name == "Breaking"
+
+            categories = await post.categories.exclude(name__icontains="news").all()
+            assert len(categories) == 1 == len(post.categories)
+            assert post.categories[0].name == "Breaking"
+
+            categories = (
+                await post.categories.filter(name__icontains="news")
+                .order_by("-name")
+                .all()
+            )
+            assert len(categories) == 2 == len(post.categories)
+            assert post.categories[0].name == "Weather News"
+            assert post.categories[1].name == "News"
+
+            categories = await post.categories.fields("name").all()
+            assert len(categories) == 3 == len(post.categories)
+            for cat in post.categories:
+                assert cat.sort_order is None
+
+            categories = await post.categories.exclude_fields("sort_order").all()
+            assert len(categories) == 3 == len(post.categories)
+            for cat in post.categories:
+                assert cat.sort_order is None
+                assert cat.subject.name is None
+
+            categories = await post.categories.select_related("subject").all()
+            assert len(categories) == 3 == len(post.categories)
+            for cat in post.categories:
+                assert cat.subject.name is not None
+
+            categories = await post.categories.prefetch_related("subject").all()
+            assert len(categories) == 3 == len(post.categories)
+            for cat in post.categories:
+                assert cat.subject.name is not None