Test

.github/workflows/ci-dev.yaml

@@ -32,3 +32,6 @@ jobs:
 
       - name: Build
         run: npm run build
+
+      - name: Run Tests
+        run: npm run test

.github/workflows/ci-full.yaml

@@ -33,6 +33,9 @@ jobs:
       - name: Build
         run: npm run build
 
+      - name: Run Tests
+        run: npm run test
+
   tag:
     name: Version tag
     needs: [check]

.gitignore

@@ -7,6 +7,9 @@ dist
 # TypeScript cache
 *.tsbuildinfo
 
+# Test coverage
+coverage/
+
 # Optional npm cache directory
 .npm
 

CHANGELOG.md

@@ -5,6 +5,25 @@ 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).
 
+## [Unreleased]
+
+### Added
+
+- Unit testing infrastructure using Vitest
+- Comprehensive test coverage (~68%) for core modules:
+  - `commandLine.ts` (84.56%): CLI argument parsing and validation
+  - `file.ts` (100%): File operations and duplicate detection
+  - `cppCode.ts` (96.62%): C++ code generation and templates
+  - `consoleColor.ts` (100%): Console utilities
+- Test fixtures for validating file processing
+- Coverage reports with HTML output
+- Development documentation for testing in README.md and CLAUDE.md
+
+### Changed
+
+- Updated `.gitignore` to exclude `coverage/` directory
+- Enhanced documentation with testing sections
+
 ## [1.10.0] - 2025-11-20
 
 ### Changed

CLAUDE.md

@@ -26,7 +26,16 @@ npm run dev:psychic
 # Development with live reload (psychic2 engine)
 npm run dev:psychic2
 
-# Run comprehensive tests (requires PlatformIO)
+# Run TypeScript unit tests
+npm run test
+
+# Run tests in watch mode
+npm run test:watch
+
+# Generate test coverage report
+npm run test:coverage
+
+# Run comprehensive ESP32 tests (requires PlatformIO)
 npm run test:all
 ```
 
@@ -119,6 +128,53 @@ npx tsx src/index.ts -e psychic -s ./demo/svelte/dist -o ./output.h --etag=true
 - **Prettier**: 120 character line width, single quotes, no trailing commas
 - **Import Sorting**: Automatic import organization with `simple-import-sort`
 
+### Testing
+
+The project uses **Vitest** for unit testing with comprehensive coverage:
+
+**Test Structure:**
+
+```
+test/
+├── unit/
+│   ├── commandLine.test.ts    # CLI argument parsing tests
+│   ├── file.test.ts            # File operations tests
+│   ├── cppCode.test.ts         # C++ code generation tests
+│   └── consoleColor.test.ts    # Console utilities tests
+└── fixtures/
+    └── sample-files/           # Test fixture files
+```
+
+**Test Coverage (68.25% overall):**
+
+- `commandLine.ts`: 84.56% - CLI argument parsing, validation, engine/tri-state validation
+- `file.ts`: 100% - File collection, duplicate detection (SHA256), pre-compressed file skipping
+- `cppCode.ts`: 96.62% - Template rendering for all 4 engines, etag/gzip combinations, Handlebars helpers
+- `cppCodeEspIdf.ts`: 100% - ESP-IDF template (tested via `cppCode.ts`)
+- `consoleColor.ts`: 100% - ANSI color code wrapping
+- `index.ts`: 0% - Main entry point (has side effects, tested via integration)
+
+**Key Testing Features:**
+
+- **Vitest Configuration**: `vitest.config.ts` with TypeScript support, 60% coverage thresholds
+- **Mocking Strategy**: Uses `vi.mock()` for file system (`node:fs`), glob (`tinyglobby`), and module dependencies
+- **Dynamic Imports**: Tests use dynamic imports for `commandLine.ts` to test different CLI arguments without side effects
+- **Test Fixtures**: Small sample files (HTML/CSS/JS) for testing file processing pipeline
+- **Coverage Reports**: Generated in `coverage/` directory (ignored by git), viewable HTML reports at `coverage/index.html`
+
+**Testing Approach:**
+
+- **commandLine.test.ts**: Tests argument parsing (`--flag=value`, `-f value`, `--flag value`), validation errors, required arguments, directory validation. Uses dynamic imports to avoid module side effects.
+- **file.test.ts**: Mocks file system with `memfs`, tests duplicate detection, compressed file skipping, path handling
+- **cppCode.test.ts**: Tests template selection by engine, code generation for all etag/gzip combinations, byte array conversion, ETag/cache headers, default route detection
+- **consoleColor.test.ts**: Simple tests for ANSI escape code wrapping (quick coverage wins)
+
+**Running Tests:**
+
+- `npm run test` - Run all tests once (CI/CD)
+- `npm run test:watch` - Watch mode for development
+- `npm run test:coverage` - Generate coverage reports
+
 ### Demo Projects
 
 - **`demo/svelte/`**: Example Svelte application with Vite, TailwindCSS, gallery images

README.md

@@ -37,6 +37,51 @@ This npm package provides a solution for **inserting any JS client application i
 - Node.js >= 20
 - npm >= 9
 
+### Development
+
+#### Testing
+
+The project includes comprehensive unit tests using Vitest:
+
+```bash
+# Run tests once
+npm run test
+
+# Run tests in watch mode (for development)
+npm run test:watch
+
+# Generate coverage report
+npm run test:coverage
+```
+
+**Test Coverage:** ~68% overall with focus on core functionality:
+
+- `commandLine.ts`: 84.56% - CLI argument parsing and validation
+- `file.ts`: 100% - File operations and duplicate detection
+- `cppCode.ts`: 96.62% - C++ code generation and templates
+- `consoleColor.ts`: 100% - Console output utilities
+
+Coverage reports are generated in the `coverage/` directory and can be viewed by opening `coverage/index.html` in a browser.
+
+#### Code Quality
+
+```bash
+# Check formatting
+npm run format:check
+
+# Fix formatting
+npm run format:fix
+
+# Check linting
+npm run lint:check
+
+# Fix linting issues
+npm run lint:fix
+
+# Fix all formatting and linting issues
+npm run fix
+```
+
 ### Usage
 
 **Install package** as devDependency (it is practical if the package is part of the project so that you always receive updates)

eslint.config.mjs

@@ -18,6 +18,7 @@ export default [
     ignores: [
       '**/.DS_Store',
       '**/node_modules',
+      '**/coverage',
       '**/bin',
       '**/dist',
       '**/demo',