Example of async.waterfall, see http://stackoverflow.com/questions/20749359/node-async-waterfall-using-an-array-with-callbacks-that-have-arguments

output.txt

~/tmp ❯❯❯ node index.js
null
[ {}, {}, {} ]

waterfall.js

var async = require('async');

var FabricCommand = function() {};
FabricCommand.prototype.do = function (undoArray, callback) {
    // Check the number of arguments
    // (the first function of the waterfall receives only a callback)
    if (Array.prototype.slice.apply(arguments).length === 1) {
        callback = undoArray;
        undoArray = undefined;
    }

    var self = this;

    if (undoArray === undefined) {
        undoArray = [];
    }

    undoArray.push(self);
    callback(null, undoArray);
};

var doCommands = [];

var f1 = new FabricCommand();
var f2 = new FabricCommand();
var f3 = new FabricCommand();

doCommands.push(f1.do.bind(f1));
doCommands.push(f2.do.bind(f2));
doCommands.push(f3.do.bind(f3));

async.waterfall(
    doCommands,
    function (err, undoCommands) {
        console.log(err);
        console.log(undoCommands);
    }
);