Guardfile

guard :test do
    watch(%r{^test/.+_test\.rb$})
    watch('test/test_helper.rb')  { 'test' }

    # Non-rails
    watch(%r{^lib/(.+)\.rb$}) { |m| "test/#{m[1]}_test.rb" }

    # Rails 4
    # watch(%r{^app/(.+)\.rb})                               { |m| "test/#{m[1]}_test.rb" }
    # watch(%r{^app/controllers/application_controller\.rb}) { 'test/controllers' }
    # watch(%r{^app/controllers/(.+)_controller\.rb})        { |m| "test/integration/#{m[1]}_test.rb" }
    # watch(%r{^app/views/(.+)_mailer/.+})                   { |m| "test/mailers/#{m[1]}_mailer_test.rb" }
    # watch(%r{^lib/(.+)\.rb})                               { |m| "test/lib/#{m[1]}_test.rb" }

    # Rails < 4
    watch(%r{^app/models/(.+)\.rb$})                   { |m| "test/unit/#{m[1]}_test.rb" }
    watch(%r{^app/controllers/(.+)\.rb$})              { |m| "test/functional/#{m[1]}_test.rb" }
    watch(%r{^app/views/(.+)/.+\.erb$})                { |m| "test/functional/#{m[1]}_controller_test.rb" }
    watch(%r{^app/views/.+$})                          { 'test/integration' }
    watch('app/controllers/application_controller.rb') { ['test/functional', 'test/integration'] }
end


guard :shell do
    watch %r{^app/assets/javascripts/(.+)\.js$} do |m|
        `casperjs test test/casperjs/*.js`
    end
    watch %r{^test/casperjs/.+$} do |m|
        `casperjs test test/casperjs/*.js`
    end
end