Rails 3.1.5 will not boot with master

[tpitale]

gem 'rails', '3.1.5'
gem 'ember-rails', github: 'emberjs/ember-rails'

Results in:

/Users/tpitale/.rvm/gems/ruby-1.9.2-p320@docket/bundler/gems/ember-rails-82d35eb582d4/lib/ember/rails/engine.rb:19:in block in <class:Engine>': undefined methodregister_engine' for nil:NilClass (NoMethodError)

That line is app.assets.register_engine …

Rails documentation doesn't mention app.assets anywhere I could find.

I had to remove the lines from the engine and put them in application.rb like this:

config.assets.register_engine '.handlebars', Ember::Handlebars::Template
config.assets.register_engine '.hbs', Ember::Handlebars::Template
config.assets.register_engine '.hjs', Ember::Handlebars::Template

[tpitale]

The issue was that due to upgrading the app from Rails 2 to 3.1 in the past I had Bundler.require before the railtie requires. It must be after the requires.