[8.x] Get queueable relationship when collection has non-numeric keys

[standaniels]

Given there is a Post model with a has many relationship to Translation models and Translation models have a locale attribute, which is unique for every Post. For easier accessing the related Translation models, the collection of translations could be keyed by the locale attribute, so that getting a Translation model for locale nl is possible by calling $post->translations->get('nl').

This would be the Post model class.

class Post extends Model
{
    public function translations(): HasMany
    {
        return $this->hasMany(Translation::class);
    }
}

And this would be the Translation model class.

class Translation extends Model
{
    public function newCollection(array $models = []): Collection
    {
        return parent::newCollection($models)->keyBy('locale');
    }
}

This is where an issue arises. By dispatching a job which requires an instance of Post, $post->getQueueableRelations() is called by the SerializesAndRestoresModelIdentifiers trait. It then fails with the following errors, as demonstrated in the test in this PR.

On PHP 7.3 and 7.4:

Cannot unpack array with string keys

On PHP 8.0:

array_intersect() does not accept unknown named parameters

A solution would be to change array_intersect(...$relations) to array_intersect(...array_values($relations)), which obviously would drop any keys.

I've applied this change locally and all the tests that I can run without any further configuration (some require additional modules) pass. What do you think?

[driesvints]

Yeah I think that change makes sense @standaniels.