Description:
I am using the PropertyInfo component to read phpdoc comments.
Somewhere we got :

    /**
     * Array of categories IDs
     * @var array|null
     * @SWG\Property(@SWG\Items(type="string"))
     */

and in our code $type->isNullable() returns "false".
$type is a Symfony\Component\PropertyInfo\Type instance.

Fix:
https://github.com/symfony/symfony/blob/3.2/src/Symfony/Component/PropertyInfo/Util/PhpDocTypeHelper.php#L107
The "nullable" argument should be used here i believe ?

I can provide a pull request to fix this if you agree that it is an issue (not sure if the argument is unused on purpose here ..)