Talks - Liz Acosta: Mock It Till You Make It: How to Verify Your External Mocks Without Ever...

Unit tests should be descriptive, automatic, independent, repeatable and deterministic with precise assertions

Mocking is essential for modern software testing to isolate components and control dependencies, but should be used judiciously:

• Only mock what you need
• Keep mocks simple
• Occasionally verify mocks for accuracy
• Don’t mock what you don’t own

Use auto_spec=True when mocking to ensure mocks stay true to the original object’s methods and attributes

The @patch decorator helps target and replace specific objects with mocks during testing

Skip tests can be used to separate tests into different environments (dev vs prod) and control when tests run

Complex mocking (mocks within mocks) is often a code smell indicating need to refactor

Unit tests serve as documentation - they help new developers understand code functionality

Mocks can fall out of sync with reality and make tests meaningless if not maintained properly

Test failures should help identify actual issues rather than mock configuration problems

Writing tests makes us better engineers by forcing us to consider expected behaviors and proper system design