add skip_reverse parameter, add links to related libs, fix weakref error, fix through error with extra=forbid

tests/test_relations/test_skipping_reverse.py

@@ -0,0 +1,223 @@
+from typing import List, Optional
+
+import databases
+import pytest
+import sqlalchemy
+
+import ormar
+from tests.settings import DATABASE_URL
+
+database = databases.Database(DATABASE_URL)
+metadata = sqlalchemy.MetaData()
+
+
+class BaseMeta(ormar.ModelMeta):
+    database = database
+    metadata = metadata
+
+
+class Author(ormar.Model):
+    class Meta(BaseMeta):
+        pass
+
+    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(BaseMeta):
+        tablename = "categories"
+
+    id: int = ormar.Integer(primary_key=True)
+    name: str = ormar.String(max_length=40)
+
+
+class Post(ormar.Model):
+    class Meta(BaseMeta):
+        pass
+
+    id: int = ormar.Integer(primary_key=True)
+    title: str = ormar.String(max_length=200)
+    categories: Optional[List[Category]] = ormar.ManyToMany(Category, skip_reverse=True)
+    author: Optional[Author] = ormar.ForeignKey(Author, skip_reverse=True)
+
+
+@pytest.fixture(autouse=True, scope="module")
+def create_test_database():
+    engine = sqlalchemy.create_engine(DATABASE_URL)
+    metadata.create_all(engine)
+    yield
+    metadata.drop_all(engine)
+
+
+@pytest.fixture(scope="function")
+async def cleanup():
+    yield
+    async with database:
+        PostCategory = Post.Meta.model_fields["categories"].through
+        await PostCategory.objects.delete(each=True)
+        await Post.objects.delete(each=True)
+        await Category.objects.delete(each=True)
+        await Author.objects.delete(each=True)
+
+
+def test_model_definition():
+    category = Category(name="Test")
+    author = Author(first_name="Test", last_name="Author")
+    post = Post(title="Test Post", author=author)
+    post.categories = category
+
+    assert post.categories[0] == category
+    assert post.author == author
+
+    with pytest.raises(AttributeError):
+        assert author.posts
+
+    with pytest.raises(AttributeError):
+        assert category.posts
+
+    assert "posts" not in category._orm
+
+
+@pytest.mark.asyncio
+async def test_assigning_related_objects(cleanup):
+    async with database:
+        guido = await Author.objects.create(first_name="Guido", last_name="Van Rossum")
+        post = await Post.objects.create(title="Hello, M2M", author=guido)
+        news = await Category.objects.create(name="News")
+
+        # Add a category to a post.
+        await post.categories.add(news)
+        # other way is disabled
+        with pytest.raises(AttributeError):
+            await news.posts.add(post)
+
+        assert await post.categories.get_or_none(name="no exist") is None
+        assert await post.categories.get_or_none(name="News") == news
+
+        # Creating columns object from instance:
+        await post.categories.create(name="Tips")
+        assert len(post.categories) == 2
+
+        post_categories = await post.categories.all()
+        assert len(post_categories) == 2
+
+        category = await Category.objects.select_related("posts").get(name="News")
+        with pytest.raises(AttributeError):
+            assert category.posts
+
+
+@pytest.mark.asyncio
+async def test_quering_of_related_model_works_but_no_result(cleanup):
+    async with database:
+        guido = await Author.objects.create(first_name="Guido", last_name="Van Rossum")
+        post = await Post.objects.create(title="Hello, M2M", author=guido)
+        news = await Category.objects.create(name="News")
+
+        await post.categories.add(news)
+
+        post_categories = await post.categories.all()
+        assert len(post_categories) == 1
+
+        assert "posts" not in post.dict().get("categories", [])[0]
+
+        assert news == await post.categories.get(name="News")
+
+        posts_about_python = await Post.objects.filter(categories__name="python").all()
+        assert len(posts_about_python) == 0
+
+        # relation not in dict
+        category = (
+            await Category.objects.select_related("posts")
+            .filter(posts__author=guido)
+            .get()
+        )
+        assert category == news
+        assert "posts" not in category.dict()
+
+        # relation not in json
+        category2 = (
+            await Category.objects.select_related("posts")
+            .filter(posts__author__first_name="Guido")
+            .get()
+        )
+        assert category2 == news
+        assert "posts" not in category2.json()
+
+        assert "posts" not in Category.schema().get("properties")
+
+
+@pytest.mark.asyncio
+async def test_removal_of_the_relations(cleanup):
+    async with database:
+        guido = await Author.objects.create(first_name="Guido", last_name="Van Rossum")
+        post = await Post.objects.create(title="Hello, M2M", author=guido)
+        news = await Category.objects.create(name="News")
+        await post.categories.add(news)
+        assert len(await post.categories.all()) == 1
+        await post.categories.remove(news)
+        assert len(await post.categories.all()) == 0
+
+        with pytest.raises(AttributeError):
+            await news.posts.add(post)
+        with pytest.raises(AttributeError):
+            await news.posts.remove(post)
+
+        await post.categories.add(news)
+        await post.categories.clear()
+        assert len(await post.categories.all()) == 0
+
+        await post.categories.add(news)
+        await news.delete()
+        assert len(await post.categories.all()) == 0
+
+
+@pytest.mark.asyncio
+async def test_selecting_related(cleanup):
+    async with database:
+        guido = await Author.objects.create(first_name="Guido", last_name="Van Rossum")
+        guido2 = await Author.objects.create(
+            first_name="Guido2", last_name="Van Rossum"
+        )
+
+        post = await Post.objects.create(title="Hello, M2M", author=guido)
+        post2 = await Post.objects.create(title="Bye, M2M", author=guido2)
+
+        news = await Category.objects.create(name="News")
+        recent = await Category.objects.create(name="Recent")
+
+        await post.categories.add(news)
+        await post.categories.add(recent)
+        await post2.categories.add(recent)
+
+        assert len(await post.categories.all()) == 2
+        assert (await post.categories.limit(1).all())[0] == news
+        assert (await post.categories.offset(1).limit(1).all())[0] == recent
+        assert await post.categories.first() == news
+        assert await post.categories.exists()
+
+        # still can order
+        categories = (
+            await Category.objects.select_related("posts")
+            .order_by("posts__title")
+            .all()
+        )
+        assert categories[0].name == "Recent"
+        assert categories[1].name == "News"
+
+        # still can filter
+        categories = await Category.objects.filter(posts__title="Bye, M2M").all()
+        assert categories[0].name == "Recent"
+        assert len(categories) == 1
+
+        # same for reverse fk
+        authors = (
+            await Author.objects.select_related("posts").order_by("posts__title").all()
+        )
+        assert authors[0].first_name == "Guido2"
+        assert authors[1].first_name == "Guido"
+
+        authors = await Author.objects.filter(posts__title="Bye, M2M").all()
+        assert authors[0].first_name == "Guido2"
+        assert len(authors) == 1