pytest-factoryboy

2.8.1 · active · verified Sat Apr 11

pytest-factoryboy is a pytest plugin that integrates factory_boy for easily creating test data within your pytest tests. It provides fixtures for generating instances of your factory_boy factories, streamlining setup for database models or complex objects. As of version 2.8.1, it's actively maintained with a stable release cadence.

Warnings

breaking The `fb` fixture, common in older versions, was removed in `pytest-factoryboy` 2.0.0. Attempting to use it will result in a `FixtureLookupError`.
Fix: Migrate your tests to use the `factory` fixture instead. For example, change `def my_fixture(fb):` to `def my_fixture(factory):` and `fb.MyFactory()` to `factory(MyFactory)()`.
breaking Factory resolution and discovery mechanisms underwent significant changes in `pytest-factoryboy` 2.0.0. Tests relying on implicit factory discovery or specific naming conventions from 1.x might break.
Fix: Ensure your factories are explicitly linked or passed to the `factory` fixture, e.g., `factory(UserFactory)`. Review the official documentation for the updated factory discovery process if you're experiencing issues with factories not being found.
gotcha Factories defined directly within test functions or nested scopes might not be properly discovered or utilized by `pytest-factoryboy`.
Fix: Define your `factory_boy` factories in `conftest.py` or dedicated `factories.py` modules that are importable and visible to your pytest suite. This ensures consistent discovery and reuse across your tests.

Install

pip install pytest-factoryboy Install stable version

Imports

factory (fixture)
```
def test_something(factory): ...
```
The `factory` fixture is automatically discovered and injected by pytest. You do not need to import it explicitly.

Quickstart

This quickstart demonstrates how to define a `factory_boy` factory for a simple `User` class, then use the `pytest-factoryboy` provided `factory` fixture to create a specific `user_factory` fixture. This `user_factory` can then be used in your tests to create single instances, batches, or instances with overridden attributes.

import pytest
import factory

# Assume a simple data model for demonstration
class User:
    def __init__(self, username, email):
        self.username = username
        self.email = email

    def __repr__(self):
        return f"User(username='{self.username}', email='{self.email}')"

# Define your factory_boy factory (e.g., in factories.py or conftest.py)
class UserFactory(factory.Factory):
    class Meta:
        model = User # Link to your actual model/class

    username = factory.Sequence(lambda n: f'user{n}')
    email = factory.LazyAttribute(lambda o: f'{o.username}@example.com')

# In your conftest.py or test file, define a fixture that uses `pytest-factoryboy`'s `factory` fixture
@pytest.fixture
def user_factory(factory):
    # `factory` is provided by pytest-factoryboy, it returns a callable bound to UserFactory
    return factory(UserFactory)

# Now use your `user_factory` in tests
def test_create_single_user(user_factory):
    user = user_factory()
    assert user.username.startswith('user')
    assert user.email.endswith('@example.com')
    assert isinstance(user, User)

def test_create_multiple_users(user_factory):
    users = user_factory.create_batch(3)
    assert len(users) == 3
    assert all(isinstance(u, User) for u in users)

def test_create_user_with_override(user_factory):
    user = user_factory(username='admin_user', email='admin@example.com')
    assert user.username == 'admin_user'
    assert user.email == 'admin@example.com'

view raw JSON →