`object|<Class>` docblocks in `DispatchTrait` break metadata warmup under symfony/type-info 7.4 (`Cannot create union with both "object" and class type`)

[schmunk42]

API Platform version

4.3.13

PHP version

8.4

Description

api-platform/core 4.3 ships redundant union docblocks of the form
object|<Class> in its own source:

• src/Symfony/Messenger/DispatchTrait.php:28 → @param object|Envelope $message
• src/Doctrine/Common/Messenger/DispatchTrait.php:28 → @param object|Envelope $message

With symfony/type-info 7.4 installed, the PhpStanExtractor that API Platform
wires as api_platform.property_info.php_stan_extractor throws an Exception while building
the type graph whenever it parses such a docblock:

Symfony\Component\TypeInfo\Exception\InvalidArgumentException:
Cannot create union with both "object" and class type.
  at vendor/symfony/type-info/Type/UnionType.php:75

object|Envelope is redundant — object already subsumes every class type.
The legacy symfony/property-info Type model tolerated this; symfony/type-info
7.4 rejects it hard.

This regressed cache:clear / routing warmup on the Symfony 7.3 → 7.4 bump.

Relation to #8201 / #8206

PR #8206 (released in 4.3.10) isolated the framework property_info service
from API Platform's extractors via private api_platform.property_info.* tags +
a bridge compiler pass. That fixed the path where API Platform's PhpStanExtractor
leaked into the framework service (Sylius @template T of object crash).

It does not cover this case: API Platform's own PhpStanExtractor still
parses object|<Class> docblocks during metadata warmup and hits the same
type-info exception. The remaining 4.3 path is still affected.

How to reproduce

Minimal standalone reproduction (public packages only, no app kernel needed):
https://gist.github.com/schmunk42/3357f3d0fdffe11e977812900355cefd

composer install
php repro.php

PHP            : 8.4.22
api-platform/core: v4.3.13
symfony/type-info: v7.4.9
symfony/property-info: v7.4.8
------------------------------------------------------------
[KO]  Symfony\Component\TypeInfo\Exception\InvalidArgumentException: Cannot create union with both "object" and class type.
      thrown from: .../symfony/type-info/Type/UnionType.php:75

The gist invokes the exact extractor API Platform wires as
api_platform.property_info.php_stan_extractor directly
Title:

---

on a property whose
docblock mirrors the DispatchTrait shape (@var object|Envelope).

You can also confirm the offending docblocks directly:

grep -rn "object|Envelope" vendor/api-platform/core/src
# src/Doctrine/Common/Messenger/DispatchTrait.php:28
# src/Symfony/Messenger/DispatchTrait.php:28

Possible solution

Drop the redundant |Envelope from both DispatchTrait docblocks — the
method already declares object $message / : Envelope in the signature, so
the docblock carries no extra information:

-    /**
-     * @param object|Envelope $message
-     */
     private function dispatch(object $message): Envelope

(or @param object $message if a docblock is desired). This keeps the source
free of redundant unions that symfony/type-info 7.4 rejects.