Doctrine\MongoDB\Tests\Query\BuilderTest::testDeepClone PHP Method

    public function testDeepClone()
    {
        $qb = $this->getTestQueryBuilder();
        $qb->field('username')->equals('jwage');
        $this->assertCount(1, $qb->getQueryArray());
        $qb2 = clone $qb;
        $qb2->field('firstName')->equals('Jon');
        $this->assertCount(1, $qb->getQueryArray());
    }