Add spec for status 422 using empty note string

app/controllers/concerns/notes_actions.rb

@@ -64,7 +64,7 @@ module NotesActions
         end
 
         if @note.errors.present? && @note.errors.keys != [:commands_only]
-          render json: json, status: 422
+          render json: json, status: :unprocessable_entity
         else
           render json: json
         end

spec/controllers/projects/notes_controller_spec.rb

@@ -259,6 +259,17 @@ describe Projects::NotesController do
         end
       end
 
+      context 'the note does not have commands_only errors' do
+        context 'for empty note' do
+          let(:note_text) { '' }
+          let(:extra_request_params) { { format: :json } }
+
+          it "returns status 422 for json" do
+            expect(response).to have_gitlab_http_status(422)
+          end
+        end
+      end
+
       context 'the project is a private project' do
         let(:project_visibility) { Gitlab::VisibilityLevel::PRIVATE }