Raise an error if respond_with is invoked and no format is declared.

actionpack/lib/action_controller/metal/mime_responds.rb

@@ -215,7 +215,10 @@ def respond_to(*mimes, &block)
     # a proc to it.
     #
     def respond_with(*resources, &block)
-      if response = retrieve_response_from_mimes([], &block)
+      raise "In order to use respond_with, first you need to declare the formats your " <<
+            "controller responds to in the class level" if mimes_for_respond_to.empty?
+
+      if response = retrieve_response_from_mimes(&block)
         options = resources.extract_options!
         options.merge!(:default_response => response)
         (options.delete(:responder) || responder).call(self, resources, options)
@@ -246,9 +249,9 @@ def collect_mimes_from_class_level #:nodoc:
     # Collects mimes and return the response for the negotiated format. Returns
     # nil if :not_acceptable was sent to the client.
     #
-    def retrieve_response_from_mimes(mimes, &block)
+    def retrieve_response_from_mimes(mimes=nil, &block)
       collector = Collector.new { default_render }
-      mimes = collect_mimes_from_class_level if mimes.empty?
+      mimes ||= collect_mimes_from_class_level
       mimes.each { |mime| collector.send(mime) }
       block.call(collector) if block_given?
 

actionpack/test/controller/mime_responds_test.rb

@@ -461,31 +461,27 @@ def test_format_with_custom_response_type_and_request_headers
 
 class RespondWithController < ActionController::Base
   respond_to :html, :json
-  respond_to :xml, :except => :using_defaults
-  respond_to :js,  :only => [ :using_defaults, :using_resource ]
+  respond_to :xml, :except => :using_resource_with_block
+  respond_to :js,  :only => [ :using_resource_with_block, :using_resource ]
 
-  def using_defaults
-    respond_to do |format|
-      format.csv { render :text => "CSV" }
-    end
+  def using_resource
+    respond_with(resource)
   end
 
-  def using_defaults_with_type_list
-    respond_to(:js, :xml)
+  def using_resource_with_block
+    respond_with(resource) do |format|
+      format.csv { render :text => "CSV" }
+    end
   end
 
-  def default_overwritten
-    respond_to do |format|
+  def using_resource_with_overwrite_block
+    respond_with(resource) do |format|
       format.html { render :text => "HTML" }
     end
   end
 
-  def using_resource
-    respond_with(Customer.new("david", 13))
-  end
-
   def using_resource_with_collection
-    respond_with([Customer.new("david", 13), Customer.new("jamis", 9)])
+    respond_with([resource, Customer.new("jamis", 9)])
   end
 
   def using_resource_with_parent
@@ -493,16 +489,16 @@ def using_resource_with_parent
   end
 
   def using_resource_with_status_and_location
-    respond_with(Customer.new("david", 13), :location => "http://test.host/", :status => :created)
+    respond_with(resource, :location => "http://test.host/", :status => :created)
   end
 
   def using_resource_with_responder
     responder = proc { |c, r, o| c.render :text => "Resource name is #{r.first.name}" }
-    respond_with(Customer.new("david", 13), :responder => responder)
+    respond_with(resource, :responder => responder)
   end
 
   def using_resource_with_action
-    respond_with(Customer.new("david", 13), :action => :foo) do |format|
+    respond_with(resource, :action => :foo) do |format|
       format.html { raise ActionView::MissingTemplate.new([], "method") }
     end
   end
@@ -511,11 +507,15 @@ def using_responder_with_respond
     responder = Class.new(ActionController::Responder) do
       def respond; @controller.render :text => "respond #{format}"; end
     end
-    respond_with(Customer.new("david", 13), :responder => responder)
+    respond_with(resource, :responder => responder)
   end
 
 protected
 
+  def resource
+    Customer.new("david", 13)
+  end
+
   def _render_js(js, options)
     self.content_type ||= Mime::JS
     self.response_body = js.respond_to?(:to_js) ? js.to_js : js
@@ -527,12 +527,18 @@ class InheritedRespondWithController < RespondWithController
   respond_to :xml, :json
 
   def index
-    respond_with(Customer.new("david", 13)) do |format|
+    respond_with(resource) do |format|
       format.json { render :text => "JSON" }
     end
   end
 end
 
+class EmptyRespondWithController < ActionController::Base
+  def index
+    respond_with(Customer.new("david", 13))
+  end
+end
+
 class RespondWithControllerTest < ActionController::TestCase
   tests RespondWithController
 
@@ -547,56 +553,54 @@ def teardown
     ActionController::Base.use_accept_header = false
   end
 
-  def test_using_defaults
+  def test_using_resource
+    @request.accept = "text/javascript"
+    get :using_resource
+    assert_equal "text/javascript", @response.content_type
+    assert_equal '$("body").visualEffect("highlight");', @response.body
+
+    @request.accept = "application/xml"
+    get :using_resource
+    assert_equal "application/xml", @response.content_type
+    assert_equal "<name>david</name>", @response.body
+
+    @request.accept = "application/json"
+    assert_raise ActionView::MissingTemplate do
+      get :using_resource
+    end
+  end
+
+  def test_using_resource_with_block
     @request.accept = "*/*"
-    get :using_defaults
+    get :using_resource_with_block
     assert_equal "text/html", @response.content_type
     assert_equal 'Hello world!', @response.body
 
     @request.accept = "text/csv"
-    get :using_defaults
+    get :using_resource_with_block
     assert_equal "text/csv", @response.content_type
     assert_equal "CSV", @response.body
 
-    @request.accept = "text/javascript"
-    get :using_defaults
-    assert_equal "text/javascript", @response.content_type
-    assert_equal '$("body").visualEffect("highlight");', @response.body
-  end
-
-  def test_using_defaults_with_type_list
-    @request.accept = "*/*"
-    get :using_defaults_with_type_list
-    assert_equal "text/javascript", @response.content_type
-    assert_equal '$("body").visualEffect("highlight");', @response.body
-
     @request.accept = "application/xml"
-    get :using_defaults_with_type_list
+    get :using_resource
     assert_equal "application/xml", @response.content_type
-    assert_equal "<p>Hello world!</p>\n", @response.body
+    assert_equal "<name>david</name>", @response.body
   end
 
-  def test_default_overwritten
-    get :default_overwritten
+  def test_using_resource_with_overwrite_block
+    get :using_resource_with_overwrite_block
     assert_equal "text/html", @response.content_type
     assert_equal "HTML", @response.body
   end
 
-  def test_using_resource
-    @request.accept = "text/javascript"
-    get :using_resource
-    assert_equal "text/javascript", @response.content_type
-    assert_equal '$("body").visualEffect("highlight");', @response.body
-
+  def test_not_acceptable
     @request.accept = "application/xml"
-    get :using_resource
-    assert_equal "application/xml", @response.content_type
-    assert_equal "<name>david</name>", @response.body
+    get :using_resource_with_block
+    assert_equal 406, @response.status
 
-    @request.accept = "application/json"
-    assert_raise ActionView::MissingTemplate do
-      get :using_resource
-    end
+    @request.accept = "text/javascript"
+    get :using_resource_with_overwrite_block
+    assert_equal 406, @response.status
   end
 
   def test_using_resource_for_post_with_html_redirects_on_success
@@ -831,22 +835,12 @@ def test_using_resource_with_set_responder
     RespondWithController.responder = ActionController::Responder
   end
 
-  def test_not_acceptable
-    @request.accept = "application/xml"
-    get :using_defaults
-    assert_equal 406, @response.status
-
-    @request.accept = "text/html"
-    get :using_defaults_with_type_list
-    assert_equal 406, @response.status
-
-    @request.accept = "application/json"
-    get :using_defaults_with_type_list
-    assert_equal 406, @response.status
-
-    @request.accept = "text/javascript"
-    get :default_overwritten
-    assert_equal 406, @response.status
+  def test_error_is_raised_if_no_respond_to_is_declared_and_respond_with_is_called
+    @controller = EmptyRespondWithController.new
+    @request.accept = "*/*"
+    assert_raise RuntimeError do
+      get :index
+    end
   end
 
   private

actionpack/test/fixtures/respond_with/using_defaults.js.rjs

-page[:body].visual_effect :highlight
\ No newline at end of file

actionpack/test/fixtures/respond_with/using_defaults_with_type_list.js.rjs

-page[:body].visual_effect :highlight
\ No newline at end of file

actionpack/test/fixtures/respond_with/using_defaults_with_type_list.xml.builder

-xml.p "Hello world!"
\ No newline at end of file