1 files changed, 51 insertions, 19 deletions
diff --git a/actionpack/lib/action_dispatch/request/utils.rb b/actionpack/lib/action_dispatch/request/utils.rb
index 9d4f1aa3c5..bb3df3c311 100644
--- a/actionpack/lib/action_dispatch/request/utils.rb
+++ b/actionpack/lib/action_dispatch/request/utils.rb
@@ -1,32 +1,64 @@
 module ActionDispatch
-  class Request < Rack::Request
+  class Request
     class Utils # :nodoc:
 
       mattr_accessor :perform_deep_munge
       self.perform_deep_munge = true
 
-      class << self
-        # Remove nils from the params hash
-        def deep_munge(hash, keys = [])
-          return hash unless perform_deep_munge
+      def self.normalize_encode_params(params)
+        if perform_deep_munge
+          NoNilParamEncoder.normalize_encode_params params
+        else
+          ParamEncoder.normalize_encode_params params
+        end
+      end
+
+      def self.check_param_encoding(params)
+        case params
+        when Array
+          params.each { |element| check_param_encoding(element) }
+        when Hash
+          params.each_value { |value| check_param_encoding(value) }
+        when String
+          unless params.valid_encoding?
+            # Raise Rack::Utils::InvalidParameterError for consistency with Rack.
+            # ActionDispatch::Request#GET will re-raise as a BadRequest error.
+            raise Rack::Utils::InvalidParameterError, "Non UTF-8 value: #{params}"
+          end
+        end
+      end
 
-          hash.each do |k, v|
-            keys << k
-            case v
-            when Array
-              v.grep(Hash) { |x| deep_munge(x, keys) }
-              v.compact!
-              if v.empty?
-                hash[k] = nil
-                ActiveSupport::Notifications.instrument("deep_munge.action_controller", keys: keys)
-              end
-            when Hash
-              deep_munge(v, keys)
+      class ParamEncoder # :nodoc:
+        # Convert nested Hash to HashWithIndifferentAccess.
+        #
+        def self.normalize_encode_params(params)
+          case params
+          when Array
+            handle_array params
+          when Hash
+            if params.has_key?(:tempfile)
+              ActionDispatch::Http::UploadedFile.new(params)
+            else
+              params.each_with_object({}) do |(key, val), new_hash|
+                new_hash[key] = normalize_encode_params(val)
+              end.with_indifferent_access
             end
-            keys.pop
+          else
+            params
           end
+        end
+
+        def self.handle_array(params)
+          params.map! { |el| normalize_encode_params(el) }
+        end
+      end
 
-          hash
+      # Remove nils from the params hash
+      class NoNilParamEncoder < ParamEncoder # :nodoc:
+        def self.handle_array(params)
+          list = super
+          list.compact!
+          list
         end
       end
     end