JS + Browserify: Function not accessible/defined after Browserify build

Question

I have defined a self firing function.

'use strict'

var test = (function(){
    console.log('This should log to console immediately.')
    function testMe() {
        console.log('Test successful!')
    }
    return {
        testMe: testMe
    }
})()

When the browser loads the script, the function fires and the output is logged to the console. Likewise, test.testMe() results in a log to the cosole.

However, I want to include a number of NPM modules is my project. To to do this, I am using Browserify.

The problem is, that the Browserify built code doesn't work the same way. The outer function fires immediately but the inner funcion cannot be accessed with test.testMe() . I get an error instead:

index.html:32 Uncaught ReferenceError: test is not defined

Why? How can I make the function available as before? Why does the code behave differently after going through Browserify?

For reference, here is the browserified code:

(function e(t,n,r){function s(o,u){if(!n[o]){if(!t[o]){var a=typeof require=="function"&&require;if(!u&&a)return a(o,!0);if(i)return i(o,!0);var f=new Error("Cannot find module '"+o+"'");throw f.code="MODULE_NOT_FOUND",f}var l=n[o]={exports:{}};t[o][0].call(l.exports,function(e){var n=t[o][1][e];return s(n?n:e)},l,l.exports,e,t,n,r)}return n[o].exports}var i=typeof require=="function"&&require;for(var o=0;o<r.length;o++)s(r[o]);return s})({1:[function(require,module,exports){
// main.js
var test = (function(){
    console.log('This should log to console immediately.')
    function testMe() {
        console.log('Test successful!')
    }
    return {
        testMe: testMe
    }
})()

},{}]},{},[1]);

Answer 1

Why?

As you can see in the browserified code, your code is now inside a function, which means that test is declared locally to that function. You cannot access it in the console because it is not global.

How can I make the function available as before?

You can either explicitly create a global variable or export the object and configure browserify to expose that export .

Why does the code behave differently after going through Browserify?

The browserfied code is different than your code. Also see the first paragraph.