Remove dupplication with logic.

Signed-off-by: Hermann Mayer <hermann.mayer92@gmail.com>

lib/grape/api/instance.rb

@@ -193,6 +193,7 @@ def cascade?
       # cannot handle.
       #
       # rubocop:disable Metrics/AbcSize because of the complex workflow
+      # rubocop:disable Metrics/MethodLength dito
       def add_head_not_allowed_methods_and_options_methods
         routes_map = {}
 
@@ -207,11 +208,12 @@ def add_head_not_allowed_methods_and_options_methods
             route_settings[:requirements] = route.requirements
             route_settings[:path] = route.origin
             route_settings[:methods] ||= []
-            route_settings[:methods] << route.request_method
+            if route.request_method == '*' || route_settings[:methods].include?('*')
+              route_settings[:methods] = Grape::Http::Headers::SUPPORTED_METHODS
+            else
+              route_settings[:methods] << route.request_method
+            end
             route_settings[:endpoint] = route.app
-
-            # using the :any shorthand produces [nil] for route methods, substitute all manually
-            route_settings[:methods] = Grape::Http::Headers::SUPPORTED_METHODS.dup if route_settings[:methods].include?('*')
           end
         end
 
@@ -242,6 +244,7 @@ def add_head_not_allowed_methods_and_options_methods
         end
       end
       # rubocop:enable Metrics/AbcSize
+      # rubocop:enable Metrics/MethodLength
 
       # Generate a route that returns an HTTP 405 response for a user defined
       # path on methods not specified