'tree' console command, in PHP.

tree.php

#!/usr/bin/php
<?php
/**
 * Because you want "tree", but cannot find the source code quick enough
 * on the web to compile for OS.X or there is no suitable implementation
 * on windows.
 */

// set error reporting
error_reporting(E_STRICT | E_ALL);

// handle command line arguments
$arg_count = $_SERVER['argc'];

if ($arg_count > 1 && $_SERVER['argv'][$arg_count-1]{0} != '-') {
    $path = $_SERVER['argv'][$arg_count-1];
} else {
    $path = getcwd();
}

$options = getopt('e::', array('exclude::'));

if (isset($path) && file_exists($path)) {
    $path = realpath($path);
} else {
    die('Could not find path: ' . $path . PHP_EOL);
}

// create the tree's RecursiveDirectoryIterator (and tree iterator)
$recursiveIterator = $treeIterator = new Tree_RecursiveDirectoryIterator($path);

// if we need to exclude anything, set the RDI to a Filter Iterator
// using the TreeIterator as the source to iterate
if (isset($options['exclude']) || isset($options['e'])) {
    Tree_RecursiveFilterIterator::$pattern = (isset($options['e'])) ? $options['e'] : $options['exclude'];
    $recursiveIterator = new Tree_RecursiveFilterIterator($treeIterator);
}

// pass the target iterator to a iteratoriterator
foreach (new Tree_RecursiveIteratorIterator($recursiveIterator) as $item) {
    echo $item . PHP_EOL;
}

/**
 * Class to handle the iteration of the filesystem
 */
class Tree_RecursiveDirectoryIterator extends RecursiveDirectoryIterator
{
    public function current()
    {
        return $this->getFilename();
    }
}

/**
 * Class to handle the filtering of items inside a RecrusiveIterator
 */
class Tree_RecursiveFilterIterator extends RecursiveFilterIterator
{
    public static $pattern = null;
    public function accept()
    {
        $regex = '#^' . self::$pattern . '#';
        if ($this->isDir() && preg_match($regex, $this->current() . DIRECTORY_SEPARATOR)) {
            return false;
        }
        return true;
    }
}

/**
 * Class to handle the actual iteration of the nodes.
 */
class Tree_RecursiveIteratorIterator extends RecursiveIteratorIterator
{
    function __construct($treeRecursiveIterator)
    {
        parent::__construct(
            new RecursiveCachingIterator(
                $treeRecursiveIterator, 
                CachingIterator::CALL_TOSTRING|CachingIterator::CATCH_GET_CHILD
                ),
            parent::SELF_FIRST
            );
    }

    function current()
    {
        $tree = '';
        for ($l=0; $l < $this->getDepth(); $l++) {
            $tree .= $this->getSubIterator($l)->hasNext() ? '| ' : '  ';
        }
        
        return $tree 
            . ($this->getSubIterator($l)->hasNext() ? '|- ' : '`- ') 
            . $this->getSubIterator($l)->__toString();
    }

    function __call($func, $params)
    {
        return call_user_func_array(array($this->getSubIterator(), $func), $params);
    }
    
}