[Laravel] `required` constraints on relationships are not automatically disabled for PATCH operations

[ttskch]

API Platform version(s) affected: 4.2.11

Description

For example, we have the following Article and Comment models.

<?php
// app/Models/Article.php

namespace App\Models;

use ApiPlatform\Metadata\ApiResource;
use Illuminate\Database\Eloquent\Model;
use Illuminate\Database\Eloquent\Relations\HasMany;

#[ApiResource(
    rules: [
        'title' => ['required', 'max:255'],
        'content' => ['required'],
    ],
)]
class Article extends Model
{
    public function comments(): HasMany
    {
        return $this->hasMany(Comment::class);
    }
}

<?php
// app/Models/Comment.php

namespace App\Models;

use ApiPlatform\Metadata\ApiResource;
use Illuminate\Database\Eloquent\Model;
use Illuminate\Database\Eloquent\Relations\BelongsTo;

#[ApiResource(
    rules: [
        'article' => ['required'],
        'content' => ['required'],
    ],
)]
class Comment extends Model
{
    public function article(): BelongsTo
    {
        return $this->belongsTo(Article::class);
    }
}

Normally, required validation rules are automatically removed for PATCH operations.

In fact, the following API request does not result in an error:

PATCH /api/articles/1

{}

And the following API request correctly results in an error:

PATCH /api/articles/1

{
  "title": {256+ char text}
}

However, for the validation rule of the article relation field in the Comment model, required is not automatically removed for PATCH operations.

The following API request:

PATCH /api/comments/1

{}

Results in the following error:

{
  "@context": "/api/contexts/ValidationError",
  "@id": "/api/validation_errors/47cdb5bda5dce8dd",
  "@type": "ValidationError",
  "description": "The article field is required.",
  "type": "/validation_errors/47cdb5bda5dce8dd",
  "title": "Validation Error",
  "detail": "The article field is required.",
  "status": 422,
  "violations": [
    {
      "propertyPath": "article",
      "message": "The article field is required."
    }
  ]
}