3 files changed, 11 insertions, 3 deletions
diff --git a/actionpack/lib/action_dispatch/http/mime_type.rb b/actionpack/lib/action_dispatch/http/mime_type.rb
index 2d49ad661c..553f19b5bc 100644
--- a/actionpack/lib/action_dispatch/http/mime_type.rb
+++ b/actionpack/lib/action_dispatch/http/mime_type.rb
@@ -331,6 +331,7 @@ to:
       @@html_types.include?(to_sym) || @string =~ /html/
     end
 
+    def all?; false; end
 
     private
 
@@ -348,6 +349,11 @@ to:
     def respond_to_missing?(method, include_private = false) #:nodoc:
       method.to_s.ends_with? '?'
     end
+
+    class All < Type
+      def all?; true; end
+      def html?; true; end
+    end
   end
 
   class NullType
diff --git a/actionpack/lib/action_dispatch/http/mime_types.rb b/actionpack/lib/action_dispatch/http/mime_types.rb
index d349cf2807..0af3e5c0df 100644
--- a/actionpack/lib/action_dispatch/http/mime_types.rb
+++ b/actionpack/lib/action_dispatch/http/mime_types.rb
@@ -33,4 +33,4 @@ Mime::Type.register "application/pdf", :pdf, [], %w(pdf)
 Mime::Type.register "application/zip", :zip, [], %w(zip)
 
 # Create Mime::ALL but do not add it to the SET.
-Mime::Type.add_type :ALL, Mime::Type.new("*/*", :all, [])
+Mime::Type.add_type :ALL, Mime::Type::All.new("*/*", :all, [])
diff --git a/actionpack/test/dispatch/mime_type_test.rb b/actionpack/test/dispatch/mime_type_test.rb
index 520864b7d9..791c6ff625 100644
--- a/actionpack/test/dispatch/mime_type_test.rb
+++ b/actionpack/test/dispatch/mime_type_test.rb
@@ -163,10 +163,12 @@ class MimeTypeTest < ActiveSupport::TestCase
     types.each do |type|
       mime = Mime::Type[type.upcase]
       assert mime.respond_to?("#{type}?"), "#{mime.inspect} does not respond to #{type}?"
-      assert mime.send("#{type}?"), "#{mime.inspect} is not #{type}?"
+      assert_equal type, mime.symbol, "#{mime.inspect} is not #{type}?"
       invalid_types = types - [type]
       invalid_types.delete(:html) if Mime::Type.html_types.include?(type)
-      invalid_types.each { |other_type| assert !mime.send("#{other_type}?"), "#{mime.inspect} is #{other_type}?" }
+      invalid_types.each { |other_type|
+        assert_not_equal mime.symbol, other_type, "#{mime.inspect} is #{other_type}?"
+      }
     end
   end