compare object properties and show diff in PHP

Something like the following, which iterates through and does a recursive diff is the item in the array is itself an array could work:

Des similar work to array_diff, but it does a check to see if it is an array first (is_array) and if so, sets the diff for that key to be the diff for that array. Repeats recursively.

function recursive_array_diff($a1, $a2) {     $r = array();     foreach ($a1 as $k => $v) {        if (array_key_exists($k, $a2)) {             if (is_array($v)) {                 $rad = recursive_array_diff($v, $a2[$k]);                 if (count($rad)) { $r[$k] = $rad; }             } else {                 if ($v != $a2[$k]) {                     $r[$k] = $v;                 }            }        } else {             $r[$k] = $v;         }     }     return $r; }

It then works like this:

$obj1 = new StdClass; $obj1->prop = array(1,2);$obj2 = new StdClass; $obj2->prop = array(1,3);print_r(recursive_array_diff((array)$obj1, (array)$obj2));/* Output:    Array    (        [prop] => Array            (                [1] => 2            )    )*/

My solution will recursively diff a stdClass and all it nested arrays and stdClass objects.It is meant to be used for comparison of rest api responses.

function objDiff($obj1, $obj2):array {     $a1 = (array)$obj1;    $a2 = (array)$obj2;    return arrDiff($a1, $a2);}function arrDiff(array $a1, array $a2):array {    $r = array();    foreach ($a1 as $k => $v) {        if (array_key_exists($k, $a2)) {             if ($v instanceof stdClass) {                 $rad = objDiff($v, $a2[$k]);                 if (count($rad)) { $r[$k] = $rad; }             }else if (is_array($v)){                $rad = arrDiff($v, $a2[$k]);                  if (count($rad)) { $r[$k] = $rad; }             // required to avoid rounding errors due to the             // conversion from string representation to double            } else if (is_double($v)){                 if (abs($v - $a2[$k]) > 0.000000000001) {                     $r[$k] = array($v, $a2[$k]);                 }            } else {                 if ($v != $a2[$k]) {                     $r[$k] = array($v, $a2[$k]);                 }            }        } else {             $r[$k] = array($v, null);         }     }     return $r;     } 

Here is a comparison function that I built using the pattern:

function objEq(stdClass $obj1, stdClass $obj2):bool {     $a1 = (array)$obj1;    $a2 = (array)$obj2;    return arrEq($a1, $a2);}function arrEq(array $a1, array $a2):bool {    foreach ($a1 as $k => $v) {        if (array_key_exists($k, $a2)) {             if ($v instanceof stdClass) {                 $r = objEq($v, $a2[$k]);                 if ($r === false) return false;             }else if (is_array($v)){                $r = arrEq($v, $a2[$k]);                  if ($r === false) return false;             } else if (is_double($v)){             // required to avoid rounding errors due to the             // conversion from string representation to double                if (abs($v - $a2[$k]) > 0.000000000001) {                     return false;                 }            } else {                 if ($v != $a2[$k]) {                     return false;                 }            }        } else {             return false;         }     }     return true;     }

Usage:

$apiResponse = apiCall(GET, $objId);$responseObj = json_decode($apiResponse);// do stuff ...if(!objEq($myObj, $responseObj) apiCall(PUT, $myObj, $objId);

Note that the apiCall function is just a mock to illustrate the concept.Also this solution is incomplete because it does not take into account any key->value pairs that are unique to obj2. In my use case this is not required and could be neglected.

NB: I borrowed heavily from Peter Hamiltons contribution. If you like what I did then please upvote his solution. Thanks!