Testing Anti-Patterns

Overview

Tests must verify real behavior, not mock behavior. Mocks are a means to isolate, not the thing being tested.

Core principle: Test what the code does, not what the mocks do.

Following strict TDD prevents these anti-patterns. See the Test-Driven Development skill (available in the skill library) for the complete TDD workflow.

When to Use This Skill

Activate this skill when:

• Writing or changing tests - Verify tests cover real behavior
• Adding mocks - Ensure mocking is necessary and correct
• Reviewing test failures - Check if mock behavior is the issue
• Tempted to add test-only methods - STOP and reconsider
• Tests feel overly complex - Sign of over-mocking