Development with Rake Pipeline and Guard

Assetfile.rb

# vim: filetype=ruby

require 'rake-pipeline-web-filters'
require 'rake-pipeline-i18n-filters'

class Minispade < Rake::Pipeline::Web::Filters::MinispadeFilter
  def initialize(options = {})
    super
    @sourceURL = options[:source_url]
  end

  def generate_output(inputs, output)
    inputs.each do |input|
      code = input.read
      code.gsub!(%r{\s*require\s*\(\s*}, 'minispade.require(') if @rewrite_requires
      code.gsub!(%r{\s*requireAll\s*\(\s*}, 'minispade.requireAll(') if @rewrite_requires
      code = %["use strict";\n] + code if @use_strict

      module_id = @module_id_generator.call(input)

      source = @sourceURL ? "\n//@ sourceURL=#{module_id}" : ""

      if @string_module
        contents = %{(function() {#{code}\n})();#{source}}.to_json
      else
        contents = "function() {#{code}\n}"
      end
      ret = "minispade.register('#{module_id}', #{contents});"
      output.write ret
    end
  end
end

production = ENV['FRONTENV'] == 'production'

# create a concatenated file with vendor libraries
input 'app/frontend/libraries' do
  output 'public'

  match '**/*.js' do
    concat ['jquery.js', 'handlebars.js', 'ember.js', 'ember-data.js'], 'libraries.js'
  end

  match 'libraries.js' do
    uglify :copyright => false
  end if production
end

# create a minispade version of the application used for development for better debbugin
input 'app/frontend' do
  output 'public'

  # compose templates
  match '**/*.handlebars' do
    handlebars :key_name_proc => proc { |input|
      File.join(File.dirname(input.path), File.basename(input.path, File.extname(input.path)))
    }
  end

  # compose translations
  match '**/i18n/*.yml' do
    i18n_js { 'translations.js' }
  end

  # compose application
  match '**/*.js' do
    reject /^tests|libraries/
    reject '**/tests/**/*.js'

    uglify :copyright => false do |input|
      input
    end if production

    filter Minispade, :rewrite_requires => true, :string => true, :source_url => !production,
      :module_id_generator => proc { |input|
        id = input.path.dup
        id.sub!(/\.js$/, '')
        id.sub!(/\/main$/, '')
        id
      }

    concat 'application.js'

    uglify if production
  end
end

# create a minispade version of the tests
input 'app/frontend' do
  output 'app/frontend/tests'

  match '**/tests/**/*.js' do
    reject /^tests/
    minispade :rewrite_requires => true, :string => true, :source_url => !production,
      :module_id_generator => proc { |input|
        id = input.path.dup
        id.sub!(/\.js$/, '')
        id.sub!(/\/tests\//, '/')
        "/~tests/#{id}"
      }

    concat 'application-tests.js'
  end
end if !production

Guardfile

# vim: filetype=ruby

interactor   :off
notification :growl     if /darwin/ =~ RUBY_PLATFORM
notification :libnotify if /linux/  =~ RUBY_PLATFORM

group :frontend do
  guard :shell do
    watch %r{^app/frontend/(?!tests).*(js|yml|handlebars)$} do
      # rebuild frontend app when change any *.js, *.handlebars, *.yml
      UI.info 'Start frontend build process'
      `bundle exec rakep`
      UI.info 'End frontend build process'

      message = $?.success? ? 'The build was done successfully' : 'The build is failed'
      Notifier.notify message, :title => 'Frontend App',
                      :image => ( $?.success? ? :success : :failed )

      # exec unit tests
      UI.info 'Start tests for frontend app'
      output = `mocha-phantomjs -R json app/frontend/tests/index.html`
      UI.info 'End tests for frontend app'

      if $?.success?
        message = 'All tests pass!'
      else
        errors = output.match(/"failures": (\d+),/)[1].to_i
        message = "#{errors} #{(errors > 1) ? 'tests' : 'test'} failed!"
      end

      Notifier.notify message, :title => 'Mocha Frontend Tests',
                      :image => ( $?.success? ? :success : :failed )
    end
  end
end

Using the built-in ember.js and ember-data.js packages in your build process prevent you to debug correctly the Ember code, which is sometimes a requirement when API is not mature.

I would recommend you importing the whole Ember and Ember-Data repo as for example git submodules and building them with a group of filters in your pipeline configuration, this setup has bring as many advantages during our dev process as finding ember bugs, better fw understanding ...