T5 Unabridged Permalink Slug

t5-unabridged-slug.php

<?php # -*- coding: utf-8 -*-
/**
 * Plugin Name: T5 Unabridged Permalink Slug
 * Description: Disable shortening of of sample slug in post editor.
 * Version:     2012.07.05
 * Author:      Thomas Scholz <info@toscho.de>
 * Author URI:  http://toscho.de
 * License:     MIT
 * License URI: http://www.opensource.org/licenses/mit-license.php
 *
 * Copyright (c) 2012 Thomas Scholz
 */

add_filter( 'get_sample_permalink_html', 't5_unabridge_sample_permalink', 10, 2 );

/**
 * Replaces the shortened permalink with its full form.
 *
 * @param  string $sample Permalink HTML
 * @param  int    $id Post ID
 * @return string
 */
function t5_unabridge_sample_permalink( $sample, $id )
{
	$link = get_sample_permalink( $id );
	$s1   = '<span id="editable-post-name" ';
	$s2   = '</span>';

	return preg_replace(
		'~' . $s1 . '([^>]*)>([^<]*)' . $s2 . '~Ui',
		$s1 . '$1>' . $link[1] . $s2,
		$sample
	);
}