Angular - Module '{0}' is not available! error due to folder name - angularjs

Question

Running into a weird issue with loading an Angular module.
I have a file structure like so
-ng-app
-app
-account
accountCtrl.js.coffee
-auth
authCtrl.js.coffee
-other_folders
app.js.coffee
and I'm loading accountCtrl and other controllers like so
#app/app.js.coffee
angular.module("app", [
'ngResource'
'smart-table'
'checklist-model'
'ui.router'
...
])
#app/account/accountCtrl.js.coffee
#app = angular.module('app')
app.controller 'accountCtrl', ($scope, $state) ->
....
#app/auth/authCtrl.js.coffee
#app = angular.module('app')
app.controller 'authCtrl', ($scope, $state) ->
....
But then accountCtrl throws an error
Module 'app' is not available! You either misspelled the module name
or forgot to load it. If registering a module ensure that you specify
the dependencies as the second argument.
I know the syntax is correct, because I'm loading a a few dozen other controllers with the same syntax. So I started playing around with different scenarios.
I deleted the 'account' folder
No error thrown, other controllers load normally
I renamed account folder to z-account
No error thrown, all controllers including accountCtrl load normally
So the error only occurs when the folder is named 'account' and is the first file in the 'app' folder. Any ideas what's going on?

Answer 1

Rails asset pipeline includes javascript files aphabetically, and app/account.js.coffee was being included before app/app.js.coffee, hence the missing module error.
Two solutions possible:
prefix files with an underscore to ensure it loads first like so:
_app.js.coffee
Or
Remove
//= require_tree .
in application.js and include files manually.