Modernize to 2025 standards with TDD, comprehensive testing, and antcolony conventions

[Sceat]

Summary

Complete modernization of @hydre/graphql-http to 2025 standards with test-driven development, comprehensive coverage, and antcolony backend conventions.

Key Improvements

✅ Testing Infrastructure

• Migrated to Node.js built-in test runner (node:test)
• Added comprehensive test suites for all 4 adapters (Koa, Fastify, Lambda, TinyHttp)
• 28 tests passing with 85.56% code coverage
• Error path and edge case coverage included
• c8 coverage reporting with enforced thresholds (75% lines, 70% branches)

✅ Dependencies Updated

• graphql: 16.6.0 → 16.12.0
• ESLint: 8.x → 9.17.0 (flat config)
• Prettier: 2.8.8 → 3.6.2
• Husky: 4.x → 9.1.7
• Fastify: 4.17.0 → 5.2.0
• All dev dependencies to latest stable versions
• Removed Babel (no longer needed with modern Node.js)
• Fixed security vulnerability (brace-expansion)

✅ Code Quality & Standards

• ESLint 9 flat config (eslint.config.js)
• Pino structured logging added
• TypeScript type checking enabled
• Modern JavaScript patterns enforced
• snake_case convention throughout (with backward compat)

✅ Security

• npm audit clean (0 vulnerabilities)
• Removed deprecated dependencies
• Updated packages with known CVEs

Breaking Changes

⚠️ API Parameter Naming (snake_case)

// Before (camelCase)
graphqlHTTP({ 
  buildContext: async () => ({}),
  formatError: error => error,
  rootValue: {}
})

// After (snake_case, but camelCase still supported for compat)
graphqlHTTP({
  build_context: async () => ({}),
  format_error: error => error,
  root_value: {}
})

Backward Compatibility: All adapters accept both camelCase and snake_case in request bodies (operationName / operation_name, variables works for both).

Test Coverage

File         | % Stmts | % Branch | % Funcs | % Lines
-------------|---------|----------|---------|--------
All files    |   85.56 |    91.17 |   78.57 |   85.56
 base.js     |   76.85 |       90 |      50 |   76.85
 fastify.js  |     100 |      100 |     100 |     100
 koa.js      |     100 |      100 |     100 |     100
 lambda.js   |     100 |      100 |     100 |     100
 tinyhttp.js |     100 |       75 |     100 |     100

Test Plan

• All 28 tests passing
• Coverage thresholds met (75%+ lines/statements)
• Lint passing (ESLint + Prettier)
• Security audit clean
• Backward compatibility verified (camelCase still works)
• All 4 adapters tested (Koa, Fastify, Lambda, TinyHttp)
• Error paths covered (missing query, invalid syntax, validation errors)

🤖 Generated with Claude Code