One-Dimensional Array to Nested Multi-Dimensional Array

test_array_2_nest.php

<?php

$array = array(1, 2, 3);
var_dump($array);

function array2NestedArray($array)
{
    if (is_array($array) && count($array) > 1) {
        return (array(array_shift(array_values($array)) => array2NestedArray(array_slice($array, 1))));
    } else {
        return (array(array_shift(array_values($array)) => []));
    }
}

$nested = array2NestedArray($array);
var_dump($nested);