Lab 6: Testing Principles and Test Generation

This project is a TypeScript sample workspace prepared for a SpecKit-style testing lab.

It demonstrates the full flow below:

• configure testing principles in the constitution
• generate test tasks from feature specs
• implement code and tests with a TDD workflow
• validate results with typecheck, lint, tests, and coverage

Stack

• TypeScript 5
• Jest + ts-jest
• ESLint 9
• Node.js + npm

Project Layout

.
|- .specify/memory/constitution.md
|- specs/001-user-auth/spec.md
|- specs/002-password-change/spec.md
|- specs/003-user-profile/spec.md
|- specs/001-user-auth/tasks.md
|- specs/002-password-change/tasks.md
|- specs/003-user-profile/tasks.md
|- src/auth/
|- tests/unit/auth/
|- tests/integration/auth/
|- tests/e2e/auth/
|- LAB-07-EXECUTION-CHECKLIST.md
|- stryker.config.json

What Is Implemented

Features: user authentication, password change, user profile lookup

• email validation
• password strength validation
• registration flow
• login flow
• password change flow
• profile lookup flow
• deterministic auth error codes
• in-memory repository for testable integration flow

Testing Principles Summary

The project follows the testing constitution in .specify/memory/constitution.md.

Key rules:

• TDD: RED -> GREEN -> REFACTOR
• Testing pyramid: ~70% unit, ~20% integration, ~10% E2E
• AAA test structure
• independent tests with beforeEach
• meaningful assertions only
• no testing of private internals

Commands

Install dependencies:

npm install

Run typecheck:

npm run typecheck

Run lint:

npm run lint

Run all tests:

npm test

Run unit tests only:

npm run test:unit

Run integration tests only:

npm run test:integration

Run E2E tests only:

npm run test:e2e

Generate coverage:

npm run test:coverage

Run mutation testing:

npm run test:mutation

Current Validation Status

Validated after implementing all three features:

• typecheck passes
• lint passes
• tests pass
• coverage exceeds constitution targets
• mutation testing runs successfully with Stryker

Measured coverage:

• line coverage: 96.84%
• branch coverage: 95%

Measured mutation score:

• total mutation score: 86.25%
• HTML report: reports/mutation/mutation.html

Feature Artifacts

• Feature spec: specs/001-user-auth/spec.md
• Generated tasks: specs/001-user-auth/tasks.md
• Feature spec: specs/002-password-change/spec.md
• Generated tasks: specs/002-password-change/tasks.md
• Feature spec: specs/003-user-profile/spec.md
• Generated tasks: specs/003-user-profile/tasks.md
• Lab guide: LAB-07-EXECUTION-CHECKLIST.md

Notes

• test:mutation now uses stryker.config.json with the Jest runner plugin for this TypeScript workspace.
• The current E2E layer is implemented as a high-level flow test with Jest inside this sample workspace.