Merge 1c6eafd into 02fd374

lib/grape/dsl/parameters.rb

@@ -62,7 +62,12 @@ def use(*names)
           params_block = named_params.fetch(name) do
             raise "Params :#{name} not found!"
           end
-          instance_exec(**options, &params_block)
+
+          if options.empty?
+            instance_exec(options, &params_block)
+          else
+            instance_exec(**options, &params_block)
+          end
         end
       end
       alias use_scope use

spec/grape/validations_spec.rb

@@ -1509,6 +1509,29 @@ def validate_param!(attr_name, params)
       end
     end
 
+    context 'with block and empty args' do
+      before do
+        subject.helpers do
+          params :shared_params do |empty_args|
+            optional :param, default: empty_args[:some]
+          end
+        end
+        subject.format :json
+        subject.params do
+          use :shared_params
+        end
+        subject.get '/shared_params' do
+          :ok
+        end
+      end
+
+      it 'works' do
+        get '/shared_params'
+
+        expect(last_response.status).to eq(200)
+      end
+    end
+
     context 'all or none' do
       context 'optional params' do
         before do