Integrated tests

test_integrated.py

import pytest
from django.contrib.auth.models import User
from ninja.testing import TestClient
from .models import Product, CartItem, Cart
from .endpoints import api

@pytest.fixture
def user(db): # db fixture assumed from pytest-django
    user = User.objects.create_user(username='testuser', password='testpass')
    Cart.objects.create(user=user)
    return user

@pytest.fixture
def client(user):
    return TestClient(api)

@pytest.fixture
def authenticated_client(client, user):
    client.authenticate(user)
    return client

@pytest.fixture
def product(db):
    return Product.objects.create(name='Test Product', price=10.0)

@pytest.fixture
def cart_item(db, user, product):
    return CartItem.objects.create(cart=user.cart, product=product, quantity=1)


def test_user_not_authenticated(product, client):
    response = client.post('/cart', json={'product_id': product.id, 'quantity': 1})
    assert response.status_code == 401

def test_non_existing_product_raises_404(authenticated_client):
    payload = {'product_id': 9999, 'quantity': 1}
    response = authenticated_client.post('/cart', json=payload)
    assert response.status_code == 404

def test_cart_item_quantity_incremented(authenticated_client, product, cart_item):
    payload = {'product_id': product.id, 'quantity': 1}
    response = authenticated_client.post('/cart', json=payload)
    assert response.status_code == 200
    cart_item.refresh_from_db()
    assert cart_item.quantity == 2

def test_cart_item_created_if_not_exist(authenticated_client, product):
    payload = {'product_id': product.id, 'quantity': 1}
    response = authenticated_client.post('/cart', json=payload)
    cart_item = CartItem.objects.get(cart=user.cart, product=product)
    assert response.status_code == 200
    assert cart_item.quantity == 1
    assert response.json() == {"id": product.id, "quantity": 1}