gh-vanman2024-cli-builder-plugins-cli-builder/skills/cli-testing-patterns/scripts/setup-jest-testing.sh

#!/bin/bash
#
# Setup Jest for CLI Testing (Node.js/TypeScript)
#
# This script installs and configures Jest for testing CLI applications
# Includes TypeScript support, coverage reporting, and CLI testing utilities

set -e

echo "🔧 Setting up Jest for CLI testing..."

# Check if npm is available
if ! command -v npm &> /dev/null; then
    echo "❌ Error: npm is not installed"
    exit 1
fi

# Install Jest and related dependencies
echo "📦 Installing Jest and dependencies..."
npm install --save-dev \
    jest \
    @types/jest \
    ts-jest \
    @types/node

# Create Jest configuration
echo "⚙️  Creating Jest configuration..."
cat > jest.config.js << 'EOF'
module.exports = {
  preset: 'ts-jest',
  testEnvironment: 'node',
  roots: ['<rootDir>/tests'],
  testMatch: [
    '**/__tests__/**/*.ts',
    '**/?(*.)+(spec|test).ts'
  ],
  collectCoverageFrom: [
    'src/**/*.{ts,js}',
    '!src/**/*.d.ts',
    '!src/**/*.test.ts',
    '!src/**/__tests__/**'
  ],
  coverageDirectory: 'coverage',
  coverageReporters: ['text', 'lcov', 'html'],
  coverageThresholds: {
    global: {
      branches: 70,
      functions: 70,
      lines: 70,
      statements: 70
    }
  },
  verbose: true,
  testTimeout: 10000
};
EOF

# Create tests directory structure
echo "📁 Creating test directory structure..."
mkdir -p tests/{unit,integration,helpers}

# Create test helper file
echo "📝 Creating test helpers..."
cat > tests/helpers/cli-helpers.ts << 'EOF'
import { execSync } from 'child_process';
import path from 'path';

export interface CLIResult {
  stdout: string;
  stderr: string;
  code: number;
}

export const CLI_PATH = path.join(__dirname, '../../bin/cli');

export function runCLI(args: string): CLIResult {
  try {
    const stdout = execSync(`${CLI_PATH} ${args}`, {
      encoding: 'utf8',
      stdio: 'pipe',
    });
    return { stdout, stderr: '', code: 0 };
  } catch (error: any) {
    return {
      stdout: error.stdout || '',
      stderr: error.stderr || '',
      code: error.status || 1,
    };
  }
}
EOF

# Create sample test file
echo "📝 Creating sample test file..."
cat > tests/unit/cli.test.ts << 'EOF'
import { runCLI } from '../helpers/cli-helpers';

describe('CLI Tests', () => {
  test('should display version', () => {
    const { stdout, code } = runCLI('--version');
    expect(code).toBe(0);
    expect(stdout).toMatch(/\d+\.\d+\.\d+/);
  });

  test('should display help', () => {
    const { stdout, code } = runCLI('--help');
    expect(code).toBe(0);
    expect(stdout).toContain('Usage:');
  });
});
EOF

# Create TypeScript configuration for tests
echo "⚙️  Creating TypeScript configuration..."
if [ ! -f tsconfig.json ]; then
    cat > tsconfig.json << 'EOF'
{
  "compilerOptions": {
    "target": "ES2020",
    "module": "commonjs",
    "lib": ["ES2020"],
    "outDir": "./dist",
    "rootDir": "./src",
    "strict": true,
    "esModuleInterop": true,
    "skipLibCheck": true,
    "forceConsistentCasingInFileNames": true,
    "resolveJsonModule": true,
    "declaration": true,
    "declarationMap": true,
    "sourceMap": true
  },
  "include": ["src/**/*"],
  "exclude": ["node_modules", "dist", "tests"]
}
EOF
fi

# Update package.json scripts
echo "⚙️  Updating package.json scripts..."
if [ -f package.json ]; then
    # Check if jq is available for JSON manipulation
    if command -v jq &> /dev/null; then
        # Add test scripts using jq
        tmp=$(mktemp)
        jq '.scripts.test = "jest" |
            .scripts["test:watch"] = "jest --watch" |
            .scripts["test:coverage"] = "jest --coverage" |
            .scripts["test:ci"] = "jest --ci --coverage --maxWorkers=2"' \
            package.json > "$tmp"
        mv "$tmp" package.json
    else
        echo "⚠️  jq not found. Please manually add test scripts to package.json:"
        echo '  "test": "jest"'
        echo '  "test:watch": "jest --watch"'
        echo '  "test:coverage": "jest --coverage"'
        echo '  "test:ci": "jest --ci --coverage --maxWorkers=2"'
    fi
fi

# Create .gitignore entries
echo "📝 Updating .gitignore..."
if [ -f .gitignore ]; then
    grep -qxF 'coverage/' .gitignore || echo 'coverage/' >> .gitignore
    grep -qxF '*.log' .gitignore || echo '*.log' >> .gitignore
else
    cat > .gitignore << 'EOF'
node_modules/
dist/
coverage/
*.log
.env
.env.local
EOF
fi

# Create README for tests
echo "📝 Creating test documentation..."
cat > tests/README.md << 'EOF'
# CLI Tests

## Running Tests

```bash
# Run all tests
npm test

# Run tests in watch mode
npm run test:watch

# Run tests with coverage
npm run test:coverage

# Run tests in CI mode
npm run test:ci
```

## Test Structure

- `unit/` - Unit tests for individual functions
- `integration/` - Integration tests for complete workflows
- `helpers/` - Test helper functions and utilities

## Writing Tests

Use the `runCLI` helper to execute CLI commands:

```typescript
import { runCLI } from '../helpers/cli-helpers';

test('should execute command', () => {
  const { stdout, stderr, code } = runCLI('command --flag');
  expect(code).toBe(0);
  expect(stdout).toContain('expected output');
});
```

## Coverage

Coverage reports are generated in the `coverage/` directory.
Target: 70% coverage for branches, functions, lines, and statements.
EOF

echo "✅ Jest setup complete!"
echo ""
echo "Next steps:"
echo "  1. Run 'npm test' to execute tests"
echo "  2. Add more tests in tests/unit/ and tests/integration/"
echo "  3. Run 'npm run test:coverage' to see coverage report"
echo ""
echo "📚 Test files created:"
echo "  - jest.config.js"
echo "  - tests/helpers/cli-helpers.ts"
echo "  - tests/unit/cli.test.ts"
echo "  - tests/README.md"