testing-patterns

def test_user_registration():
    # Arrange
    user_data = {"email": "test@example.com", "password": "secure123"}
 
    # Act
    result = register_user(user_data)
 
    # Assert
    assert result.success is True
    assert result.user.email == "test@example.com"

from unittest.mock import Mock, patch
 
@patch('services.email.send_email')
def test_sends_welcome_email(mock_send):
    mock_send.return_value = True
 
    register_user({"email": "test@example.com"})
 
    mock_send.assert_called_once_with(
        to="test@example.com",
        template="welcome"
    )

import pytest
from factories import UserFactory
 
@pytest.fixture
def user():
    return UserFactory.create(role="admin")
 
@pytest.fixture
def authenticated_client(user):
    client = TestClient(app)
    client.login(user)
    return client
 
def test_admin_dashboard(authenticated_client):
    response = authenticated_client.get("/admin")
    assert response.status_code == 200

@pytest.mark.integration
def test_full_checkout_flow(db_session, stripe_mock):
    # Create test data
    user = create_user()
    product = create_product(price=100)
 
    # Execute flow
    cart = add_to_cart(user, product)
    order = checkout(cart, payment_method="card")
 
    # Verify
    assert order.status == "completed"
    assert stripe_mock.charges.create.called