JARVIS codemod gist

destination.js

bar.baz();

jarvis.json

{
  "lang": "Javascript",
  "parser": "recast",
  "version": "1.0",
  "nodeOp": "replace"
}

source.js

bar();

transform.js

module.exports = function transformer(file, api) {
  const j = api.jscodeshift;
  const root = j(file.source);
  const body = root.get().value.program.body;

  let helloWorld = "HELLO WORLD GIST TRANSFORM";
  root.find(j.CallExpression, {
    callee: {
      name: "foo"
    }
  }).replaceWith(path => {
    return j.callExpression(j.memberExpression(j.identifier("foo"), j.identifier("bar"), false), []);
  });

  return root.toSource();
};