Inbound custom cast generates PHP notices when setting values to null on new model instances

[wfeller]

• Laravel Version: 7.3.0
• PHP Version: 7.4.3
• Database Driver & Version: n/a

Description:

When using inbound custom casts, and setting a value to null on an empty model, we get PHP notices of undefined index.

Setting a null initial value will try to retrieve the current value by doing $this->attributes[$key], but since $this->attributes[$key] does not exist yet, we get a PHP notice.

In HasAttributes->getClassCastableAttributeValue(), it can be solved by changing the following:

   return $this->classCastCache[$key] = $caster instanceof CastsInboundAttributes
                ? $this->attributes[$key]
                : $caster->get($this, $key, $this->attributes[$key] ?? null, $this->attributes);

Into:

   return $this->classCastCache[$key] = $caster instanceof CastsInboundAttributes
                ? ($this->attributes[$key] ?? null)
                : $caster->get($this, $key, $this->attributes[$key] ?? null, $this->attributes);

Steps To Reproduce:

class User extends Authenticatable
{
    protected $casts = ['name' => Uppercase::class];
}

class Uppercase implements CastsInboundAttributes
{
    public function set($model, string $key, $value, array $attributes)
    {
        return is_string($value) ? strtoupper($value) : $value;
    }
}

$user = new User;
$user->name = null;

[driesvints]

Indeed seems a bug to me. Can you send in a PR?

[driesvints]

I sent in a pr: #32118

[wfeller]

Thanks!