withCount triggers Illegal offset type in Builder line 355

[jbxonline]

Laravel v5.3.30
laravel-mongodb v3.2.3

I have 2 collections - one containing vehicles, the other containing statistics (vehicle views)

<?php
namespace App\Collections;
use Jenssegers\Mongodb\Eloquent\Model as Moloquent;

class Vehicle extends Moloquent {

    protected $connection = 'mongodb';
    protected $fillable = ['manufacturer', 'model', 'colour', 'features', 'branch', 'vin'];
    protected $dates = ['date_assigned'];

    public function associated_views()
    {
        return $this->hasMany('App\Collections\Statistic');
    }
}

<?php
namespace App\Collections;
use Jenssegers\Mongodb\Eloquent\Model as Moloquent;

class Statistic extends Moloquent {

    protected $connection = 'mongodb';
    protected $fillable = ['ip', 'event'];
    
    public function associated_vehicle()
    {
        return $this->belongsTo('App\Collections\Vehicle');
    }
}

And I want a simple query to give me a vehicle containing the number of views the vehicle has had:

$vehicle = Vehicle::withCount('associated_views')->find('580f3db65b3914fa56386a33');
echo $vehicle->associated_views_count;

However, this gives me an error:

in Builder.php line 355
at HandleExceptions->handleError('2', 'Illegal offset type', '/var/www/html/vendor/jenssegers/mongodb/src/Jenssegers/Mongodb/Query/Builder.php', '355', array('columns' => array('vehicles.*' => true), 'wheres' => array('_id' => object(ObjectId)), 'column' => object(Expression))) in Builder.php line 355`

Being able to include the associated_views_count in the results would give my app a huge performance boost, so seriously, any help would be much appreciated!

[HassanIbrahim]

I had the same issue with Laravel 5.5 and didn't find an official fix; so I did the following workarounds:

1. To use Accessor on the Model
public function getAssociatedViewsCountAttribute() { return $this->associated_views->count(); }

2. Simply Call the Count() method on Relation Collection

echo $vehicle->associated_views->count();

[shaedrich]

Is there a fix yet or only the above workaround?