Detect which lodash/underscore functions your code is using.

used-functions.js

var usedFunctions = function (_) {
    "use strict";

    var usedFunctions = [];
    var isFunction = _.isFunction;
    var contains = _.contains;

    _.forOwn(_, function (func, name) {
        if ( !isFunction(func) ) { return; }
        _[name] = function () {
            usedFunctions.push(name);
            _[name] = func;

            return func.apply(_, arguments);
        };
    });

    return usedFunctions;

}(window._);