Symfony version(s) affected

7.1-RC1

Description

While testing 7.1-RC1 I noticed a change in behavior.

I have a test suite that serializes all commands (for a command bus) and confirms that they can be deserialized.

There is a command that does not have any properties:

final class DoSomethingCommand {}

When this is serialized with Symfony 7.0, it produces {}.

But with Symfony 7.1-RC1 it becomes [].

How to reproduce

See above.

Possible Solution

While debugging the situation, I notice that in 7.0 the empty object gets normalized into ArrayObject (empty).

But on 7.1-RC1 it becomes an empty array.

Additional Context

No response