src/Eloquent/Concerns/DeserializesAttributes.php
protected function deserializeAttributes($attributes, $record)
    {
        return collect($attributes)->reject(function ($v, $field) use ($record) {
            return $this->isNotFillable($field, $record);
        })->mapWithKeys(function ($value, $field) use ($record) {
            $key = $this->modelKeyForField($field, $record);

            return [$key => $this->deserializeAttribute($value, $field, $record)];
        })->all();
    }
protected function deserializeAttributes($attributes, $record)
    {
        return collect($attributes)->reject(function ($v, $field) use ($record) {
            return $this->isNotFillable($field, $record);
        })->mapWithKeys(function ($value, $field) use ($record) {
            $key = $this->modelKeyForField($field, $record);

            return [$key => $this->deserializeAttribute($value, $field, $record)];
        })->all();
    }
Deserialize fillable attributes.

@param $attributes
@param $record
@return array