Description:
------------
RecursiveDirectoryIterator::getChildren uses a hard coded reference to itself in the function getChildren, so it can't be extended.
Note: It's not possible to completely overwrite getChildren without a lose of subPath handling.


In spl_directory.c:

SPL_METHOD(RecursiveDirectoryIterator, getChildren)

... 

spl_instantiate_arg_ex1(spl_ce_RecursiveDirectoryIterator, &return_value, 0, &zpath TSRMLS_CC);

...

This should be changed to something like the RecursiveFilterIterator getChildren uses:

spl_instantiate_arg_ex1(Z_OBJCE_P(getThis() ...



Reproduce code:
---------------
class RecursiveDirectoryIteratorTest extends RecursiveDirectoryIterator
{

public function test() {
    echo "test";
}

}

$di = new RecursiveIteratorIterator(new RecursiveDirectoryIteratorTest ("/somepathwithsubfolders"), RecursiveIteratorIterator::SELF_FIRST);

foreach ($di as $key => $value) {
    echo $key, " - ",$value, $di->test(),"<br>";
}



Expected result:
----------------
echoing "test" for each item.

Actual result:
--------------
Call to undefined method RecursiveDirectoryIterator::test() as soon getChildren creates a new object for a subfolder.