feat: Add comprehensive testing infrastructure with Vitest

.github/workflows/ci.yml

@@ -0,0 +1,74 @@
+name: CI
+
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+
+jobs:
+  test:
+    name: Test on ${{ matrix.os }} / Node ${{ matrix.node }}
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest, macos-latest]
+        node: ['18', '20', '22']
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: ${{ matrix.node }}
+          cache: 'npm'
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Run format check
+        run: npm run format:check
+
+      - name: Run unit tests
+        run: npm run test:unit
+
+      - name: Run integration tests
+        run: npm run test:integration
+
+      - name: Run E2E tests
+        run: npm run test:e2e
+        env:
+          ENABLE_NOTIFICATIONS: 'false'
+
+  coverage:
+    name: Coverage Report
+    runs-on: ubuntu-latest
+    needs: test
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '20'
+          cache: 'npm'
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Run tests with coverage
+        run: npm run test:coverage
+        env:
+          ENABLE_NOTIFICATIONS: 'false'
+
+      - name: Upload coverage to Codecov
+        uses: codecov/codecov-action@v4
+        with:
+          files: ./coverage/lcov.info
+          fail_ci_if_error: false
+        continue-on-error: true

CHANGELOG.md

@@ -5,16 +5,37 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [2.1.0] - 2026-01-12
+
+### Added
+
+- **Testing infrastructure**: Comprehensive test suite using Vitest
+  - Unit tests for pure functions (sanitizeServerName, parseArguments, detectPortFromOutput, getLogViewerCommand)
+  - Integration tests for config loading and health checks
+  - E2E tests for CLI commands and workflows
+- **CI/CD pipeline**: GitHub Actions workflow for automated testing
+  - Matrix testing on Ubuntu and macOS
+  - Node.js 18, 20, 22 support
+  - Code coverage reporting via Codecov
+- **Test utilities**: Helper modules for CLI execution, mock servers, and temp project setup
+- **ADR-002**: Architecture Decision Record documenting the Vitest testing strategy
+
+### Changed
+
+- Updated CLAUDE.md formatting for consistency
+
 ## [2.0.0] - 2026-01-09
 
 ### Changed
+
 - **Breaking**: Complete architecture rewrite - now a self-contained TypeScript CLI
 - **Breaking**: Switched from compiled output to running TypeScript directly via `tsx`
 - **Breaking**: Removed modular `src/` architecture in favor of single `bin/dev.ts`
 - Updated to use `tsx` instead of `ts-node` for TypeScript execution
 - Simplified package structure for easier maintenance
 
 ### Added
+
 - Native OS notifications via `node-notifier` for server events
 - `doctor` command for environment diagnostics
 - `restart` command for quick server restarts
@@ -23,13 +44,15 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Exponential backoff for health checks
 
 ### Removed
+
 - Compiled `dist/` output (no build step required)
 - Modular `src/` directory (consolidated into `bin/dev.ts`)
 - Test suite (tests were for old architecture)
 
 ## [1.0.0] - 2024-09-19
 
 ### Added
+
 - Initial release of dev
 - Core server lifecycle management (start, stop, status)
 - Process monitoring with PID tracking
@@ -44,6 +67,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Comprehensive documentation and examples
 
 ### Features
+
 - **Commands**: init, start, stop, status, port, logs, cleanup
 - **Configuration**: JSON-based server configuration
 - **Monitoring**: Real-time process health monitoring
@@ -56,6 +80,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - **Platform Support**: macOS and Linux
 
 ### Technical Details
+
 - Built with ES modules
 - Requires Node.js >=18.0.0
 - Uses child_process, fs, path, and util built-ins

CLAUDE.md

@@ -22,27 +22,32 @@ npm run format:check
 The codebase is a self-contained TypeScript CLI:
 
 ### Core Files (`bin/`)
+
 - **`dev.ts`** - Main CLI script (~1200 lines, all-in-one)
 - **`notify.ts`** - Native OS notification utility using node-notifier
 
 ### Key Concepts
 
 #### Server Configuration
+
 - Servers are defined in `.dev/servers.json` with command, preferredPort, and healthCheck
 - Template variables: `{PORT}` for dynamic port assignment, `{ROLE}` for server name
 - Automatic server inference from package.json scripts during `init`
 
 #### Process Management
+
 - PID tracking in `.dev/pid.json` with port, startTime, and status
 - Automatic port conflict resolution (tries ports sequentially)
 - Health checks before marking servers as successfully started
 - Process cleanup and stale entry detection
 
 #### Log Management
+
 - Centralized logging in `.dev/log/` directory
 - Configurable log viewers via `--log-viewer` flag or `DEV_LOG_VIEWER` environment variable
 
 ### File Structure
+
 ```
 bin/
 ├── dev.ts        # Main CLI script