二维数组根据相同值组成新数组？

Question

旧数组：

$orders=array(
array(
"ordersn"=>'2019564842348',
"proName"=>'拖鞋',
"name"=>'张三',
"phone"=>"1800952442",
"proNum"=>2,
"proPrice"=>35.85
),
array(
"ordersn"=>'2019564842348',
"proName"=>'棉签',
"name"=>'张三',
"phone"=>"1800952442",
"proNum"=>1,
"proPrice"=>12
),
array(
"ordersn"=>'25451548412487',
"proName"=>'电脑',
"name"=>'李四',
"phone"=>"1564845487",
"proNum"=>1,
"proPrice"=>4600
),
);

如何通过相同的ordersn组装成新数组:

$orders=array(
    array(
            "ordersn"=>'2019564842348',
            "product"=>array(
                    array(
                            "proName"=>'拖鞋',
                            "proNum"=>2,
                            "proPrice"=>35.85
                        ),
                    array(
                            "proName"=>'棉签',
                            "proNum"=>1,
                            "proPrice"=>12
                        ),
                ),
            "name"=>'张三',
            "phone"=>'1800952442'
        ),
    array(
            "ordersn"=>'25451548412487',
            "product"=>array(
                    array(
                            "proName"=>'电脑',
                            "proNum"=>1,
                            "proPrice"=>4600
                        ),
                ),
            "name"=>'李四',
            "phpone"=>"1564845487",
        ),
    );

Answer 1

$orders=array(
array(
"ordersn"=>'2019564842348',
"proName"=>'拖鞋',
"name"=>'张三',
"phone"=>"1800952442",
"proNum"=>2,
"proPrice"=>35.85
),
array(
"ordersn"=>'2019564842348',
"proName"=>'棉签',
"name"=>'张三',
"phone"=>"1800952442",
"proNum"=>1,
"proPrice"=>12
),
array(
"ordersn"=>'25451548412487',
"proName"=>'电脑',
"name"=>'李四',
"phone"=>"1564845487",
"proNum"=>1,
"proPrice"=>4600
),
);
$returnData = [];
foreach($orders as $k => $v){
if(isset($returnData[$v['ordersn']])){
        $returnData[$v['ordersn']]['product'][] = [
                'proName'  => $v['proName'],
                'proNum'   => $v['proNum'],
                'proPrice' => $v['proPrice'] 
        ];
    }else{
        $returnData[$v['ordersn']] = [
            'ordersn' => $v['ordersn'],
            'product' => [[
                'proName'  => $v['proName'],
                'proNum'   => $v['proNum'],
                'proPrice' => $v['proPrice'] 
            ]],
            'name'  => $v['name'],
            'phone' => $v['phone']
        ];
    }
}
print_r(array_values($returnData));die;