php - recursive array_diff()?

Question

I'm looking for some tool to give me a recursive diff of two arrays. What I envision is a web page with two color-coded tree-structures. On each tree, green are parts of the array which match in both arrays, and red is for parts of each that don't match the other. Something like the output of dBug

I have some code that gives me a nested array to populate a report. I'm developing a new method that should be faster, but I need to test the values and also the structure, to make sure it gives output identical to the old method.

Is there something out there that I can use? Or do I need to write this? Or is there another way to accomplish my goals?

Answer 1

There is one such function implemented in the comments of array_diff.

function arrayRecursiveDiff($aArray1, $aArray2) {
  $aReturn = array();

  foreach ($aArray1 as $mKey => $mValue) {
    if (array_key_exists($mKey, $aArray2)) {
      if (is_array($mValue)) {
        $aRecursiveDiff = arrayRecursiveDiff($mValue, $aArray2[$mKey]);
        if (count($aRecursiveDiff)) { $aReturn[$mKey] = $aRecursiveDiff; }
      } else {
        if ($mValue != $aArray2[$mKey]) {
          $aReturn[$mKey] = $mValue;
        }
      }
    } else {
      $aReturn[$mKey] = $mValue;
    }
  }
  return $aReturn;
} 

The implementation only handles two arrays at a time, but I do not think that really posses a problem. You could run the diff sequentially if you need the diff of 3 or more arrays at a time. Also this method uses key checks and does a loose verification.