PHP - add missing date in array (from: https://stackoverflow.com/questions/46380370/add-missing-date-index-to-array-in-php)

missing-date.php

<?php

$arr = [
           ['date' => '2019-07-31', 'total' => 4],
           ['date' => '2019-08-04', 'total' => 6],
           ['date' => '2019-08-05', 'total' => 7]
       ];

$result = [];
foreach ($arr as $k => $item) {
    $d = new DateTime($item['date']);
    $result[] = $item;
    if (isset($arr[$k+1])) {
        $diff = (new DateTime($arr[$k+1]['date']))->diff($d)->days;
        if ($diff > 1) {
            $result = array_merge($result , array_map(function($v) use($d){
                $d_copy = clone $d;
                // do something here if date doesn't exist
                return [
                    'date' => $d_copy->add(new DateInterval('P' . $v. 'D'))->format('Y-m-d'),
                    'total' => 0
                ];
            }, range(1, $diff-1)));
        }
    }
}

echo "<pre>";
print_r($result);
echo "</pre>";
die;