4 files changed, 19 insertions, 31 deletions
diff --git a/actionpack/lib/action_dispatch/http/request.rb b/actionpack/lib/action_dispatch/http/request.rb
index 8cea17c7a6..1377e53ce8 100644
--- a/actionpack/lib/action_dispatch/http/request.rb
+++ b/actionpack/lib/action_dispatch/http/request.rb
@@ -119,9 +119,9 @@ module ActionDispatch
     end
 
     # Is this a HEAD request?
-    # Equivalent to <tt>request.method_symbol == :head</tt>.
+    # Equivalent to <tt>request.request_method_symbol == :head</tt>.
     def head?
-      HTTP_METHOD_LOOKUP[method] == :head
+      HTTP_METHOD_LOOKUP[request_method] == :head
     end
 
     # Provides access to the request's HTTP headers, for example:
diff --git a/actionpack/lib/action_dispatch/middleware/head.rb b/actionpack/lib/action_dispatch/middleware/head.rb
deleted file mode 100644
index f1906a3ab3..0000000000
--- a/actionpack/lib/action_dispatch/middleware/head.rb
+++ /dev/null
@@ -1,18 +0,0 @@
-module ActionDispatch
-  class Head
-    def initialize(app)
-      @app = app
-    end
-
-    def call(env)
-      if env["REQUEST_METHOD"] == "HEAD"
-        env["REQUEST_METHOD"] = "GET"
-        env["rack.methodoverride.original_method"] = "HEAD"
-        status, headers, _ = @app.call(env)
-        [status, headers, []]
-      else
-        @app.call(env)
-      end
-    end
-  end
-end
diff --git a/actionpack/lib/action_dispatch/routing/mapper.rb b/actionpack/lib/action_dispatch/routing/mapper.rb
index a49b12621e..0a65b4dbcc 100644
--- a/actionpack/lib/action_dispatch/routing/mapper.rb
+++ b/actionpack/lib/action_dispatch/routing/mapper.rb
@@ -262,7 +262,7 @@ module ActionDispatch
       # for root cases, where the latter is the correct one.
       def self.normalize_path(path)
         path = Journey::Router::Utils.normalize_path(path)
-        path.gsub!(%r{/(\(+)/?}, '\1/') unless path =~ %r{^/\(+[^/]+\)$}
+        path.gsub!(%r{/(\(+)/?}, '\1/') unless path =~ %r{^/\(+[^)]+\)$}
         path
       end
 
@@ -917,7 +917,7 @@ module ActionDispatch
             @path       = (options[:path] || @name).to_s
             @controller = (options[:controller] || @name).to_s
             @as         = options[:as]
-            @param      = options[:param] || :id
+            @param      = (options[:param] || :id).to_sym
             @options    = options
           end
 
@@ -965,12 +965,18 @@ module ActionDispatch
             "#{path}/:#{param}"
           end
 
+          alias :shallow_scope :member_scope
+
           def new_scope(new_path)
             "#{path}/#{new_path}"
           end
 
+          def nested_param
+            :"#{singular}_#{param}"
+          end
+
           def nested_scope
-            "#{path}/:#{singular}_#{param}"
+            "#{path}/:#{nested_param}"
           end
 
         end
@@ -1481,18 +1487,18 @@ module ActionDispatch
           def nested_options #:nodoc:
             options = { :as => parent_resource.member_name }
             options[:constraints] = {
-              :"#{parent_resource.singular}_id" => id_constraint
-            } if id_constraint?
+              parent_resource.nested_param => param_constraint
+            } if param_constraint?
 
             options
           end
 
-          def id_constraint? #:nodoc:
-            @scope[:constraints] && @scope[:constraints][:id].is_a?(Regexp)
+          def param_constraint? #:nodoc:
+            @scope[:constraints] && @scope[:constraints][parent_resource.param].is_a?(Regexp)
           end
 
-          def id_constraint #:nodoc:
-            @scope[:constraints][:id]
+          def param_constraint #:nodoc:
+            @scope[:constraints][parent_resource.param]
           end
 
           def canonical_action?(action, flag) #:nodoc:
@@ -1505,7 +1511,7 @@ module ActionDispatch
 
           def path_for_action(action, path) #:nodoc:
             prefix = shallow_scoping? ?
-              "#{@scope[:shallow_path]}/#{parent_resource.path}/:id" : @scope[:path]
+              "#{@scope[:shallow_path]}/#{parent_resource.shallow_scope}" : @scope[:path]
 
             if canonical_action?(action, path.blank?)
               prefix.to_s
diff --git a/actionpack/lib/action_dispatch/routing/route_set.rb b/actionpack/lib/action_dispatch/routing/route_set.rb
index 1d6ca0c78d..0bbed6cbea 100644
--- a/actionpack/lib/action_dispatch/routing/route_set.rb
+++ b/actionpack/lib/action_dispatch/routing/route_set.rb
@@ -333,7 +333,7 @@ module ActionDispatch
           end
         end
 
-        MountedHelpers.class_eval <<-RUBY
+        MountedHelpers.class_eval(<<-RUBY, __FILE__, __LINE__ + 1)
           def #{name}
             @#{name} ||= _#{name}
           end