@OkieRazorback thanks for reporting this, but I'm afraid we'd need more information. The reason is that Symfony doesn't persist entities, it's Doctrine who does that. So, where do you think this issue happens? When submitting some info in a form, when handling some data in a request or when executing the Doctrine logic? Thanks!

This logic comme from the php json_encode function used by doctrine, so there is nothing we can do here.

You should use array_values in your entity code if you want to ensure that data is saved as a json array.

The reason I think this is happening in Symfony is if I output the request data the array is ordered properly (1,2,3) but after it runs through $form->handleRequest() it is ordered (0,2,3).

I was able to work around the issue by using array_values in a data_transformer as @jvasseur suggested.

@HeahDude would you consider this a bug of $form->handleRequest() or is this the expected behavior? Thanks!

It may come from the ResizeFormListener if this is about a collection field. But we don't have enough information to be sure of what's actually happening.

@OkieRazorback could you please create a reproducer for this bug? Thanks!

Actually it's not a bug, it is expected that on removal the listener keeps the index of each element.

So using a transformer as proposed by @jvasseur is half a solution because in your case it has to be a model transformer which does not reapply the changes on the view data if the view is generated after submission (invalid or without redirection).

So it must happen in a SUBMIT event after the ResizeFormListener.

Not sure this is worth to add such behavior in the core with a proper option like reset_indexes or if a note in doc would be enough.

closing because of the reasons given by @HeahDude

Same issue here, I was able to solve the issue adding array_values on entity: $this->propertyWithIssue = array_values($propertyWithIssue);