rollup-plugin-graphql/src/toESModules.js

Convert graphql files to ES6 modules

import { EOL } from 'os';

export default function (source) {
  if (typeof source !== "string") {
    return source;
  }

  return replaceRequires(replaceModuleExports(source));
}

function replaceModuleExports(source) {
  return source.replace('module.exports = doc', 'export default doc');
}

function replaceRequires(source) {
  const imports = {};
  let index = 0;
  
  // replace a require statement with a variable
  source = source.replace(/require\(([^)]+)\)/ig, (match, path) => {
    path = path.replace(/[\"\']+/g, '');
    
    if (!imports[path]) {
      imports[path] = `frgmt${++index}`;
    }
    
    return imports[path];
  });

  // prepare import statements
  const importsOutput = Object.keys(imports)
    .map((path) => `import ${imports[path]} from "${path}";`)
    .join(EOL);

  return importsOutput + EOL + source;
}