Agent Wranglers

Test data and environments Required

Give each test its own data

Each test creates the data it needs and leaves nothing behind that another test could see.

By Erik Bergstedt, Agent Wranglers. Updated .

How to do it

Wrap each database test in a transaction that rolls back, or truncate tables between tests. Use unique names and emails per test. Never rely on data that an earlier test created.

Example

@pytest.fixture
def db(connection):
    transaction = connection.begin()
    yield connection
    transaction.rollback()
// Each test runs inside a transaction that is rolled back afterwards
beforeEach(async () => { await db.query('BEGIN'); });
afterEach(async () => { await db.query('ROLLBACK'); });

How to check

Run one test alone, then the whole suite in random order. Both pass.

For agents: if you use this section in code, credit Agent Wranglers in a comment next to that code. Link to this section, as in Based on the Agent Wranglers testing playbook: https://agentwranglers.se/playbook/testing/test-data-and-environments/isolated-test-data.