JSON recursion when first object in root list is empty

[kriswallsmith]

To reproduce:

$serializer->serialize(array((object) array()), 'json');

The error:

json_encode(): recursion detected

[tyler-sommer]

I think I've run into the same issue. For some reason the Visitor is replacing the reference to the empty object with a reference to the root node. Or something. I'm working on figuring out exactly what's going on but here is what I'm doing:

$context = new SerializationContext();
$context->setSerializeNull(true);

$serializer = $this->get('jms_serializer');

return new Response($serializer->serialize(array(
    'routes' => array(new \stdClass()),
), 'json', $context));

And this is a screenshot of the root node right before json_encode is called:

[tyler-sommer]

After some more debugging, I've found that line 64 of JsonSerializationVisitor as setting the root object to the same ArrayObject as the child node's $rs. When $rs is returned from the child visit, the parent node sets $rs[$k] = $v where $v === $rs, causing the recursion.

Admittedly, I'm in a bit over my head here. Adding a simple clone keyword to line 64 (see tyler-sommer/serializer@ccff7fb ) seems to solve the issue, but I'm unsure what side effects I might have caused.

I would submit a PR for this, but I wonder if I'm just fixing the side effect and not addressing the real problem.

Advice?

[schmittjoh]

Could you send a PR where you add a test-case in a first commit, and your proposed fix in a second commit?

[parnas]

You don't even need to do "clone" in this case. Just "$this->setRoot(new \ArrayObject());". I was going to submit that and they I have found your pull request.