Properly check the arity for template handlers.

actionpack/lib/action_view/template.rb

@@ -275,7 +275,7 @@ module ActionView
         end
 
         arity = @handler.respond_to?(:arity) ? @handler.arity : @handler.method(:call).arity
-        code  = arity == 1 ? @handler.call(self) : @handler.call(self, view)
+        code  = arity.abs == 1 ? @handler.call(self) : @handler.call(self, view)
 
         # Make sure that the resulting String to be evalled is in the
         # encoding of the code

actionpack/test/template/render_test.rb

@@ -225,6 +225,11 @@ module RenderTestCases
     %'"#{template.class} #{view.class}"'
   end
 
+  def test_render_inline_with_render_from_to_proc
+    ActionView::Template.register_template_handler :ruby_handler, :source.to_proc
+    assert_equal '3', @view.render(:inline => "(1 + 2).to_s", :type => :ruby_handler)
+  end
+
   def test_render_inline_with_template_handler_with_view
     ActionView::Template.register_template_handler :with_view, WithViewHandler
     assert_equal 'ActionView::Template ActionView::Base', @view.render(:inline => "Hello, World!", :type => :with_view)