7.4Regex in Test Assertions

# Validate response format
import re

def test_user_id_format(api_response):
    """User IDs should be UUIDs."""
    user_id = api_response.json()["id"]
    uuid_pattern = r'^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$'
    assert re.match(uuid_pattern, user_id), f"Invalid UUID format: {user_id}"

def test_email_format(api_response):
    """Email should be valid format."""
    email = api_response.json()["email"]
    email_pattern = r'^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$'
    assert re.match(email_pattern, email), f"Invalid email format: {email}"

def test_error_message_no_stack_trace(error_response):
    """Error messages should not contain internal stack traces."""
    body = error_response.text
    assert not re.search(r'at .*\(.*:\d+:\d+\)', body), "Stack trace exposed in error"
    assert not re.search(r'Traceback \(most recent call last\)', body), "Python traceback exposed"
    assert not re.search(r'/usr/src/app', body), "Internal file paths exposed"

TypeScript Regex

test("API response contains valid ISO date", () => {
    const createdAt = response.data.created_at;
    const isoDatePattern = /^\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}/;
    expect(createdAt).toMatch(isoDatePattern);
});

test("Error response does not leak internals", () => {
    const body = JSON.stringify(errorResponse.data);
    expect(body).not.toMatch(/at .*\(.*:\d+:\d+\)/);
    expect(body).not.toMatch(/node_modules/);
});