uninitialized constant I18n::JS Ruby on Rails

Question

I am still having trouble with Ruby on Rails. I run rails s (this is for my openproject app) and I get this (before it was working). I also wanted to make a note I am now using Ruby 2.0 and I still get the same error.

require 'rails/all'... 0.850s
Bundler.require... 7.700s
/home/bistro/openproject/config/application.rb:89:in `<class:Application>': uninitialized constant I18n::JS (NameError)
        from /home/bistro/openproject/config/application.rb:61:in `<module:OpenProject>'
        from /home/bistro/openproject/config/application.rb:60:in `<top (required)>'
        from /home/bistro/.rvm/gems/ruby-1.9.3-p484/gems/railties-3.2.16/lib/rails/commands.rb:53:in `require'
        from /home/bistro/.rvm/gems/ruby-1.9.3-p484/gems/railties-3.2.16/lib/rails/commands.rb:53:in `block in <top (required)>'
        from /home/bistro/.rvm/gems/ruby-1.9.3-p484/gems/railties-3.2.16/lib/rails/commands.rb:50:in `tap'
        from /home/bistro/.rvm/gems/ruby-1.9.3-p484/gems/railties-3.2.16/lib/rails/commands.rb:50:in `<top (required)>'
        from script/rails:6:in `require'
        from script/rails:6:in `<main>'

Answer 1

I'm working on a Rails Ember app and I had exactly the same problem, trying to internationalize the client-side using the i18n-js gem (https://github.com/fnando/i18n-js). To give more context, I am following the instructions in this article: http://eviltrout.com/2013/11/24/i18n-in-ember.html

In my case, Rails did not find I18n::JS because it is now called SimplesIdeias::I18n (you can see it by running rake middleware from the command line). Adding the line

config.middleware.use SimplesIdeias::I18n::Middleware

in the application.rb file solved the problem for me, hope it helps.

Answer 2

If you happen upon this now adays. your gemfile should say something like gem 'i18n-js', ">= 3.0.0.rc11". Otherwise you will end up using version 2.0