Sokil\Mongo\DocumentRelationTest::testRemoveRelation_HasMany PHP Method

    public function testRemoveRelation_HasMany()
    {
        // collections
        $carsCollection = $this->database->getCollection('cars');
        $wheelsCollection = $this->database->getCollection('wheels');
        $carDocument = $carsCollection->createDocument(array('brand' => 'Nissan'))->save();
        $wheelDocument = $wheelsCollection->createDocument(array('car_id' => $carDocument->getId()))->save();
        $carDocument->removeRelation('wheels', $wheelDocument);
        $this->assertEmpty($carDocument->wheels);
    }