A faster load_textdomain for WordPress

a_faster_load_textdomain.php

<?php
/*
Plugin Name: A faster load_textdomain
Version: 0.0.1
Description: While we're wating for https://core.trac.wordpress.org/ticket/32052.
Author: Per Soderlind
Author URI: https://soderlind.no
Plugin URI: https://gist.github.com/soderlind/610a9b24dbf95a678c3e
License: GPL

Save the plugin in mu-plugins. You don't have to, but you should add an an object cache. See benchmarks at https://core.trac.wordpress.org/ticket/32052#comment:7

Credit: nicofuma , I just created the plugin based on his patch (https://core.trac.wordpress.org/ticket/32052)

*/

function cl_faster_load_textdomain( $retval, $domain, $mofile ) {
	global $l10n;

	if ( ! is_readable( $mofile ) ) {
		return false;
	}

	$data  = get_transient( md5( $mofile ) );
	$mtime = filemtime( $mofile );

	$mo = new MO();
	if ( ! $data || ! isset( $data['mtime'] ) || $mtime > $data['mtime'] ) {
		if ( ! $mo->import_from_file( $mofile ) ) {
			return false;
		}
		$data = array(
			'mtime'   => $mtime,
			'entries' => $mo->entries,
			'headers' => $mo->headers,
		);
		set_transient( md5( $mofile), $data );
	} else {
		$mo->entries = $data['entries'];
		$mo->headers = $data['headers'];
	}

	if ( isset( $l10n[$domain] ) ) {
		$mo->merge_with( $l10n[$domain] );
	}

	$l10n[$domain] = &$mo;

	return true;
}
add_filter( 'override_load_textdomain', 'cl_faster_load_textdomain', 1, 3 );