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lich make factory

Create test factories for generating test data.

What is a Factory?

A factory creates test data with:

  • Fake data - Realistic random values
  • Defaults - Sensible pre-filled values
  • Overrides - Customize specific fields

Usage

lich make factory <Name>

Example

$ lich make factory User

✅ Factory UserFactory created!

Files created:
  backend/tests/factories/user_factory.py

Generated Code

"""
User factory for test data generation.
"""
from uuid import uuid4
from datetime import datetime
from typing import Optional
from faker import Faker

from internal.entities.user import User

fake = Faker()


class UserFactory:
    """Factory for creating User test instances."""

    @staticmethod
    def create(
        id: Optional[str] = None,
        name: Optional[str] = None,
        email: Optional[str] = None,
        **overrides
    ) -> User:
        """
        Create a User instance with fake data.

        Args:
            id: Override ID
            name: Override name
            email: Override email
            **overrides: Any other field overrides
        """
        return User(
            id=id or uuid4(),
            name=name or fake.name(),
            email=email or fake.email(),
            created_at=datetime.utcnow(),
            **overrides
        )

    @staticmethod
    def create_batch(count: int, **overrides) -> list:
        """Create multiple User instances."""
        return [UserFactory.create(**overrides) for _ in range(count)]

Use in Tests

from tests.factories.user_factory import UserFactory

def test_user_registration():
    # Create test user
    user = UserFactory.create(
        email="test@example.com"
    )

    assert user.email == "test@example.com"
    assert user.name  # Random name

def test_list_users():
    # Create 10 test users
    users = UserFactory.create_batch(10)

    assert len(users) == 10

Why Use Factories?

Benefit Description
🎲 Realistic Data Faker generates real-looking data
⚡ Speed Create test data quickly
🔧 Flexible Override only what you need
🧹 Clean Tests No verbose setup code

See Also