react-native/local-cli/link/android/patches/makePackagePatch.js

const applyParams = require('./applyParams');

module.exports = function makePackagePatch(packageInstance, params, prefix) {
  const processedInstance = applyParams(packageInstance, params, prefix);

  return {
    pattern: 'new MainReactPackage()',
    patch: ',\n            ' + processedInstance,
  };
};