dependency-cruiser/test/extractor-fixtures/cjs/require-tester.js

Validate and visualize javascript dependencies. With your rules. ES6, CommonJS, AMD

// you can find things like this in UMD and AMD wrappers
var weHaveARequireAlready=typeof require=="function"&&require;

if (typeof require==="function") {
    // do interesting stuff
};

doStuff(typeof require==="function");