Unit Testing

Conduct sensitivity analyses to test robustness of findings. Use when: (1) Testing assumption violations, (2) Meta-analysis robustness, (3) Handling missing data, (4) Examining outliers.

Pick and run the smallest correct validation step (checks → focused Jest by path → broader suites). Use whenever you modify code and need confidence quickly.

Use when implementing any feature or bugfix before writing implementation code

Guide for writing Go tests following this project's patterns including httptest, test organization, and coverage requirements.

Generate comprehensive test suites ensuring 80%+ coverage for DevPortfolio. Use when asked to write tests, generate test suites, increase coverage, or create test cases. Generates Vitest + React Testing Library tests following AAA pattern with accessibility and i18n tests.

Introduce test-driven development to beginners with simple Flask/Sinatra test examples and TDD concepts

Develop and test API routes in the Next.js App Router. Use this when the user asks to create, modify, test, or debug API endpoints, handle API responses, validate request parameters, or work with the /api directory.

Design and implement visual regression testing for UI changes. Definesscreenshot coverage, rendering stabilization, baseline management, and CIintegration (e.g., Playwright screenshots, Percy/Chromatic). Use whenUI/styling/layout changes need protection against regressions, or when addingscreenshot-based tests to a web/WASM/desktop UI.

This skill should be used when estimating development time for Jira tickets. It provides both manual and AI-assisted estimates with T-shirt sizes, story points, and phase-by-phase time breakdowns based on task type classification, complexity scoring, and project architecture (monolithic/serverless/frontend/fullstack/mobile/test_automation).

Test Nuxt 3 / Nitro API handlers with real PostgreSQL, transaction rollback isolation, and typed factories. No mocks, real SQL.

Automatically troubleshoot unexpected results OR command/script errors without user request. Triggers when: (1) unexpected behavior - command succeeded but expected effect didn't happen, missing expected errors, wrong output, silent failures; (2) explicit failures - stderr, exceptions, non-zero exit, SDK/API errors. Applies systematic diagnosis using error templates, hypothesis testing, and web research for any Stack Overflow-worthy issue.

Guides test creation for Polibase following strict testing standards. Activates when writing tests or creating test files. Enforces external service mocking (no real API calls), async/await patterns, test independence, and proper use of pytest-asyncio to prevent CI failures and API costs.

Guides on analyzing and improving test coverage for Python (pytest-cov) and JavaScript (c8) projects. Use when a user asks to set up test coverage, generate coverage reports, understand why coverage is low, or improve their test coverage.

Test n8n nodes using Jest, nock for HTTP mocking, and local testing workflows with npm link. Use this skill when writing test files in __tests__ folders, mocking HTTP requests with nock, creating mock IExecuteFunctions contexts, testing helper functions, setting up golden file tests, running the linter before publishing, or locally testing nodes in the n8n UI. Apply when organizing test files, mocking external APIs, validating node execution output, or following the pre-publish checklist.

Run ruff + pytest and fix issues minimally.

Best practices for writing Python tests - use when creating or improving test coverage

Vitest setup and best practices. Use when configuring Vitest for TypeScript projects.

Review Prisma code for common violations, security issues, and performance anti-patterns found in AI coding agent stress testing. Use when reviewing Prisma Client usage, database operations, or performing code reviews on projects using Prisma ORM.

Automates visual regression testing for Storybook components using cloud-based snapshot comparison. Use when setting up visual testing, catching UI regressions, or reviewing component changes.

🔄 PHP-QA-CI TOOL ORCHESTRATOR - Automatic run→fix→run cycling for php-qa-ci tools.**ONLY for php-qa-ci pipeline tools** (./bin/qa -t toolname)NOT for ad-hoc tool execution outside php-qa-ci.Use when user requests QA tools via php-qa-ci:- "run phpstan", "use stan skills"- "run tests", "run phpunit"- "run rector", "run cs fixer"- "run allStatic", "run allCS"**CRITICAL**: MUST cycle automatically until tool reports clean OR escalation needed.DO NOT stop after one fix to ask "what next?" - KEEP CYCLING.Supports all php-qa-ci tools via ./bin/qa -t {toolname}:- phpstan (static analysis) - has fixer agent- phpunit (tests) - has fixer agent- rector (refactoring) - self-fixing, re-run until clean- fixer (code style) - self-fixing, re-run until clean- infection (mutation testing) - no auto-fix- allStatic/allCs/allTests - meta groupsAutomatically detects which tools have fixers and invokes them.**PERFORMS PREFLIGHT CHECK**: Invokes docs-conflict-checker agent to ensureproject documentation doesn