Entry point: /faion-net — invoke this skill for automatic routing to the appropriate domain.

Testing Developer Skill

Testing strategies and implementation covering unit tests, integration tests, E2E tests, TDD workflow, and testing best practices.

Purpose

Handles all aspects of software testing including test design, implementation, mocking, fixtures, and testing frameworks.

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Context Discovery

Auto-Investigation

Detect testing setup from project:

Signal	How to Check	What It Tells Us
pytest.ini or pyproject.toml [tool.pytest]	Glob("**/pytest.ini")	pytest used
conftest.py	Glob("**/conftest.py")	pytest fixtures exist
jest.config.*	Glob("**/jest.config.*")	Jest used
vitest.config.*	Glob("**/vitest.config.*")	Vitest used
*_test.go	Glob("**/*_test.go")	Go tests exist
playwright.config.*	Glob("**/playwright.config.*")	E2E with Playwright
cypress/	Glob("**/cypress/**")	E2E with Cypress
Coverage config	Grep("coverage", "**/package.json")	Coverage enabled

Read existing patterns:

• Check existing tests for patterns (AAA, fixtures)
• Read conftest.py for shared fixtures
• Check CI for test commands

Discovery Questions

Q1: Testing Goal

question: "What testing help do you need?"
header: "Goal"
multiSelect: false
options:
  - label: "Write tests for existing code"
    description: "Add test coverage"
  - label: "Set up testing framework"
    description: "Configure from scratch"
  - label: "TDD for new feature"
    description: "Write tests first"
  - label: "Fix flaky tests"
    description: "Stabilize test suite"
  - label: "Improve coverage"
    description: "Find and fill gaps"

Q2: Test Level

question: "What level of testing?"
header: "Level"
multiSelect: true
options:
  - label: "Unit tests"
    description: "Test individual functions/classes"
  - label: "Integration tests"
    description: "Test components together"
  - label: "E2E tests"
    description: "Test full user flows"
  - label: "API tests"
    description: "Test HTTP endpoints"

Routing:

• "Unit" → unit-testing, mocking-strategies
• "Integration" → integration-testing, test containers
• "E2E" → e2e-testing, Playwright/Cypress
• "API" → api-testing, contract testing

Q3: Test Framework (if not detected)

question: "Which test framework?"
header: "Framework"
multiSelect: false
options:
  - label: "pytest (Python)"
    description: "Python testing framework"
  - label: "Jest (JavaScript)"
    description: "JavaScript testing"
  - label: "Vitest (JavaScript)"
    description: "Fast Vite-native testing"
  - label: "Go testing"
    description: "Built-in Go testing"
  - label: "Playwright (E2E)"
    description: "Cross-browser E2E"

Q4: Mocking Needs

question: "What do you need to mock?"
header: "Mocking"
multiSelect: true
options:
  - label: "External APIs"
    description: "HTTP calls to third parties"
  - label: "Database"
    description: "DB queries and transactions"
  - label: "Time/dates"
    description: "Freeze time for tests"
  - label: "File system"
    description: "File operations"
  - label: "Nothing / minimal mocking"
    description: "Prefer real dependencies"

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When to Use

• Unit testing strategies
• Integration testing
• End-to-end (E2E) testing
• Test-driven development (TDD)
• Mocking and stubbing
• Test fixtures and factories
• Security testing
• Code coverage analysis
• Language-specific testing (pytest, Jest, Go testing, etc.)

Methodologies

Category	Methodology	File
Testing Levels
Unit testing	Unit test patterns, isolation, assertions	unit-testing.md
Integration testing	Integration test patterns, test containers	integration-testing.md
E2E testing basics	End-to-end test patterns	e2e-testing.md
E2E testing alt	E2E strategies	testing-e2e.md
Testing Practices
TDD workflow	Red-green-refactor, TDD cycle	tdd-workflow.md
Mocking strategies	Mocks, stubs, spies, fakes	mocking-strategies.md
Test fixtures	Fixture patterns, factory pattern	test-fixtures.md
Testing patterns	General testing patterns	testing-patterns.md
Security
Security testing	SAST, DAST, penetration testing	security-testing.md
Language-Specific
pytest testing	pytest fixtures, parametrize, markers	testing-pytest.md
JavaScript testing	Jest, Vitest, React Testing Library	testing-javascript.md
Go testing	Go testing stdlib, table tests	testing-go.md

Tools by Language

Python: pytest, unittest, hypothesis, factory-boy, faker JavaScript: Jest, Vitest, Mocha, Chai, React Testing Library, Cypress, Playwright Go: testing stdlib, testify, gomock Java: JUnit 5, Mockito, AssertJ C#: xUnit, NUnit, Moq, FluentAssertions

E2E: Playwright, Cypress, Selenium, Puppeteer Security: OWASP ZAP, Burp Suite, Snyk, SonarQube

Related Sub-Skills

Sub-skill	Relationship
faion-python-developer	pytest, Django testing
faion-javascript-developer	Jest, Vitest testing
faion-backend-developer	Language-specific testing
faion-api-developer	API testing, contract testing
faion-devtools-developer	Code coverage, test automation

Integration

Invoked by parent skill faion-software-developer for testing-related work.

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faion-testing-developer v1.0 | 12 methodologies