Function transpileTS

lib/utils/typescript.js:74–160

(filePath)

   * Injects CommonJS shims (require, module, exports, __dirname, __filename) as needed
   */
  const transpileTS = (filePath) => {
    const tsContent = fs.readFileSync(filePath, 'utf8')

    // Transpile TypeScript to JavaScript with ES module output
    let jsContent = transpile(tsContent, {
      module: 99, // ModuleKind.ESNext
      target: 99, // ScriptTarget.ESNext
      esModuleInterop: true,
      allowSyntheticDefaultImports: true,
      lib: ['lib.esnext.d.ts'], // Enable latest features including top-level await
      suppressOutputPathCheck: true,
      skipLibCheck: true,
    })

    // Check if the code uses CommonJS globals
    const usesCommonJSGlobals = /__dirname|__filename/.test(jsContent)
    const usesRequire = /\brequire\s*\(/.test(jsContent)
    const usesModuleExports = /\b(module\.exports|exports\.)/.test(jsContent)

    if (usesCommonJSGlobals || usesRequire || usesModuleExports) {
      // Inject ESM equivalents at the top of the file
      let esmGlobals = ''

      if (usesRequire || usesModuleExports) {
        // IMPORTANT: Use the original .ts file path as the base for require()
        // This ensures dynamic require() calls work with relative paths from the original file location
        const originalFileUrl = `file://${filePath.replace(/\\/g, '/')}`
        esmGlobals += `import { createRequire } from 'module';
import { extname as __extname } from 'path';
const __baseRequire = createRequire('${originalFileUrl}');

// Wrap require to auto-resolve extensions (mimics CommonJS behavior)
const require = (id) => {
  try {
    return __baseRequire(id);
  } catch (err) {
    // If module not found and it's a relative/absolute path without extension, try common extensions
    if (err.code === 'MODULE_NOT_FOUND' && (id.startsWith('./') || id.startsWith('../') || id.startsWith('/'))) {
      const ext = __extname(id);
      // Only treat known file extensions as real extensions (so names like .TEST don't block probing)
      const __knownExts = ['.js', '.cjs', '.mjs', '.json', '.node'];
      const hasKnownExt = ext && __knownExts.includes(ext.toLowerCase());
      if (!hasKnownExt) {
        // Try common extensions in order: .js, .cjs, .json, .node
        // Note: .ts files cannot be required - they need transpilation first
        const extensions = ['.js', '.cjs', '.json', '.node'];
        for (const testExt of extensions) {
          try {
            return __baseRequire(id + testExt);
          } catch (e) {
            // Continue to next extension
          }
        }
      }
    }
    // Re-throw original error if all attempts failed
    throw err;
  }