realpath() alternative to detect absolute path (URN and URL is not supported, only local paths on the server)

truepath_realpath_alternative.php

<?php
    /**
     * This function is to replace PHP's extremely buggy realpath().
     * @param string The original path, can be relative etc.
     * @return string The resolved path, it might not exist.
     */
    public static function truepath( $path )
    {
        // whether $path is unix or not
        $unipath = strlen( $path ) == 0 || $path{0} != '/';
        // attempts to detect if path is relative in which case, add cwd
        if ( strpos( $path, ':' ) === false && $unipath )
            $path = getcwd() . DIRECTORY_SEPARATOR . $path;
        // resolve path parts (single dot, double dot and double delimiters)
        $path      = str_replace( array( '/', '\\' ), DIRECTORY_SEPARATOR, $path );
        $parts     = array_filter( explode( DIRECTORY_SEPARATOR, $path ), 'strlen' );
        $absolutes = array();
        foreach ( $parts as $part ) {
            if ( '.' == $part ) continue;
            if ( '..' == $part ) {
                array_pop( $absolutes );
            } else {
                $absolutes[ ] = $part;
            }
        }
        $path = implode( DIRECTORY_SEPARATOR, $absolutes );
        // resolve any symlinks
        if ( file_exists( $path ) && linkinfo( $path ) > 0 ) $path = readlink( $path );
        // put initial separator that could have been lost
        $path = !$unipath ? '/' . $path : $path;
        return $path;
    }

Hi @umidjons! I really like what you've done here as I find realpath() often doesn't work well for projects that I work on. Nice work!

Would you consider providing an open-source license for this gist? I am working on a free software neuroimaging project and we are looking for a solution like this.

Please feel free to contact me via the email listed on my profile if so.