Testing Patterns

Foundational testing practices applicable across languages and frameworks.

Rules

• Write tests for happy paths and error cases
• Test edge cases and boundary conditions
• Each test should test one thing
• Tests should be deterministic and repeatable
• Use descriptive test names that explain the scenario

Checklist

• Happy path is covered
• Error cases are tested
• Edge cases are identified and tested
• Tests are independent and can run in any order
• Test data is isolated per test
• No flaky tests in the suite

Pitfalls

• Testing implementation details instead of behavior
• Not testing error paths
• Shared mutable state between tests
• Tests that depend on execution order