transform-lodash.js

module.exports = function (file, api, options) {
  const useDouble = options.useDouble || false;
  const noSemi = options.noSemi || false;
  const useRequire = options.useRequire || false;

  const j = api.jscodeshift;

  const isContainsLodashImport =
    file.source.match(/(const|let|var)\s+_\s+=\s+require\(["']lodash["']\)/g) ||
    file.source.match(/import\s+_\s+from\s+["']lodash["']/g);

  if (isContainsLodashImport) {
    return;
  } else {
    let isLodashDetected = false;
    j(file.source)
      .find(j.MemberExpression)
      .forEach((path) => {
        if (path.value.object.name === "_") {
          isLodashDetected = true;
        }
      });

    const quote = useDouble ? '"' : "'";
    const semi = noSemi ? "" : ";";
    const require = `const _ = require(${quote}lodash${quote})${semi}`;
    const es6Import = `import _ from ${quote}lodash${quote}${semi}`;
    const importString = useRequire ? require : es6Import;

    if (isLodashDetected) {
      return `${importString}\n${file.source}`;
    }
  }
};