Agent skill

Stryker Mutation Testing

Stryker mutation testing for assessing test suite quality and effectiveness

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Forks 31

Install this agent skill to your Project

npx add-skill https://github.com/a5c-ai/babysitter/tree/main/library/specializations/qa-testing-automation/skills/stryker-mutation

SKILL.md

Stryker Mutation Testing Skill

Overview

This skill provides expert-level capabilities for Stryker-based mutation testing, enabling test quality assessment by introducing code mutations and measuring test effectiveness.

Capabilities

Mutation Execution

  • Configure Stryker for JavaScript/TypeScript
  • Execute mutation testing runs
  • Configure mutation operators

Score Analysis

  • Analyze mutation score
  • Track killed vs survived mutants
  • Identify weak test assertions

Configuration

  • Configure mutators and test runners
  • Set up file patterns for mutation
  • Configure timeout settings

Reporting

  • Generate HTML mutation reports
  • Dashboard integration for tracking
  • CI/CD report generation

Optimization

  • Configure incremental mutation testing
  • Optimize mutation runs for large codebases
  • Parallel mutation execution

Test Quality Insights

  • Identify gaps in test coverage
  • Recommend assertion improvements
  • Prioritize test enhancements

Target Processes

  • mutation-testing.js - Mutation testing implementation
  • quality-gates.js - Mutation score gates
  • shift-left-testing.js - Early test quality validation

Dependencies

  • @stryker-mutator/core - Stryker core
  • Test runner plugins (jest-runner, karma-runner)
  • Reporter plugins

Usage Example

javascript
{
  kind: 'skill',
  skill: {
    name: 'stryker-mutation',
    context: {
      action: 'execute',
      configFile: 'stryker.conf.json',
      mutate: ['src/**/*.ts'],
      thresholds: {
        high: 80,
        low: 60,
        break: 50
      }
    }
  }
}

Configuration

The skill uses stryker.conf.json or stryker.conf.js and supports incremental testing for faster feedback.

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