Description:
------------
Since DirectoryIterator::current() returns itself there is many confusion while using it. It can't for instance be used as an argument of recursive method.

Test script:
---------------
foreach ( new DirectoryIterator(__DIR__) as $Current ) {
    var_dump($Di === $Current);
}

bool(true)
bool(true)
bool(true)
...

Expected result:
----------------
In order to use DirectoryIterator object as a function parameter you MUST clone it:

function iterateDirRecursive(DirectoryIterator $Di)
{
    foreach ( $Di as $Item ) {
        $Current = clone $Item; // notice the clone here
        if ( $Current->isDir() && ! $Current->isDot() ) {
            iterateDirRecursive($Current);
        }
    }
}

iterateDirRecursive(new DirectoryIterator(__DIR__));

Actual result:
--------------
Otherwise it will fail with "out of memory" or "maximum nesting level reached" depending on your PHP compilation:

function iterateDirRecursive(DirectoryIterator $Di)
{
    foreach ( $Di as $Item ) {
        $Current = $Item; // clone is missing
        if ( $Current->isDir() && ! $Current->isDot() ) {
            iterateDirRecursive($Current);
        }
    }
}

iterateDirRecursive(new DirectoryIterator(__DIR__));