Function transform

src/compiler/bundle/ext-format-plugin.ts:11–37

(code: string, importPath: string)

    name: 'extFormatPlugin',

    transform(code: string, importPath: string): TransformResult {
      if (/\0/.test(importPath)) {
        return null;
      }

      const { ext, filePath, format } = normalizeFsPathQuery(importPath);

      // ?format= param takes precedence before file extension
      switch (format) {
        case 'url':
          return { code: formatUrl(config, this, code, filePath, ext), map: null };
        case 'text':
          return { code: formatText(code, filePath), map: null };
      }

      // didn't provide a ?format= param
      // check if it's a known extension we should format
      if (ext != null && FORMAT_TEXT_EXTS.includes(ext)) {
        return { code: formatText(code, filePath), map: null };
      }

      if (ext != null && FORMAT_URL_MIME[ext]) {
        return { code: formatUrl(config, this, code, filePath, ext), map: null };
      }

      return null;
    },
  };
};