Change `POST /settings/applications/:id` to regenerate token on scopes change (#23359)

Fixes #23096

app/controllers/settings/applications_controller.rb

@@ -29,7 +29,13 @@ class Settings::ApplicationsController < Settings::BaseController
 
   def update
     if @application.update(application_params)
-      redirect_to settings_applications_path, notice: I18n.t('generic.changes_saved_msg')
+      if @application.scopes_previously_changed?
+        @access_token = current_user.token_for_app(@application)
+        @access_token.destroy
+        redirect_to settings_application_path(@application), notice: I18n.t('applications.token_regenerated')
+      else
+        redirect_to settings_application_path(@application), notice: I18n.t('generic.changes_saved_msg')
+      end
     else
       render :show
     end

spec/controllers/settings/applications_controller_spec.rb

@@ -132,7 +132,7 @@ describe Settings::ApplicationsController do
       end
 
       it 'redirects back to applications page' do
-        expect(call_update).to redirect_to(settings_applications_path)
+        expect(call_update).to redirect_to(settings_application_path(app))
       end
     end