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Testing Anti Patterns

Skill Verified Active

Never test mock behavior. Never add test-only methods to production classes. Understand dependencies before mocking. Language-agnostic principles with TypeScript/Jest and Python/pytest examples.

Purpose

To help developers write more effective, robust, and maintainable tests by identifying and preventing common anti-patterns that lead to fragile test suites and production issues.

Features

  • Identification of core testing anti-patterns
  • Language-agnostic principles
  • TypeScript/Jest and Python/pytest examples
  • Detailed detection strategies and red flags
  • Actionable fixes and prevention guidance

Use Cases

  • When writing or changing tests
  • When adding mocks to a test suite
  • During code reviews of test code
  • When debugging complex or flaky tests

Non-Goals

  • Providing a testing framework itself
  • Automating the detection of anti-patterns within a codebase
  • Teaching basic unit testing concepts

Practices

  • Test Quality
  • Test Design
  • Code Review

Installation

npx skills add bobmatnyc/claude-mpm-skills

Runs the Vercel skills CLI (skills.sh) via npx — needs Node.js locally and at least one installed skills-compatible agent (Claude Code, Cursor, Codex, …). Assumes the repo follows the agentskills.io format.

Quality Score

Verified
97 /100
Analyzed about 22 hours ago

Trust Signals

Last commit29 days ago
Stars44
LicenseMIT
Status
View Source

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