Merge pull request #3581 from hefan/master

Backend: more robust update_positions for resource controller

backend/app/controllers/spree/admin/resource_controller.rb

@@ -76,7 +76,7 @@ def create
   def update_positions
     ActiveRecord::Base.transaction do
       params[:positions].each do |id, index|
-        model_class.find(id).set_list_position(index)
+        model_class.find_by(id: id)&.set_list_position(index)
       end
     end
 

backend/spec/controllers/spree/admin/resource_controller_spec.rb

@@ -197,5 +197,17 @@ def check_destroy_constraints
     it 'updates the position of widget 2' do
       expect { subject }.to change { widget_2.reload.position }.from(2).to(1)
     end
+
+    context 'passing a not persisted item' do
+      subject do
+        post :update_positions, params: { id: widget_1.to_param,
+          positions: { widget_1.id => '2', widget_2.id => '1', 'widget' => '3' }, format: 'js' }
+      end
+
+      it 'only updates the position of persisted attributes' do
+        subject
+        expect(Widget.all.order('position')).to eq [widget_2, widget_1]
+      end
+    end
   end
 end