simple path normalizing function

simple-path-normalize.js

/**
 * UPDATE 2013-02-27 ~ This is now in repo at https://github.com/dfkaye/simple-path-normalize
 * 
 * file: simple-path-normalize.js - simple path normalizing JavaScript function -
 * author: @dfkaye - david.kaye
 * date: 2013-2-22
 *
 */
;(function (exports) {

    var BLANK = '';
    var SLASH = '/';
    var DOT = '.';
    var DOTS = DOT.concat(DOT);

    exports.normalize = normalize;
    
    function normalize(path) {

        if (!path || path === SLASH) {
            return SLASH;
        }
        
        var src = path.split(SLASH);
        var target = (path[0] === SLASH || path[0] === DOT) ? [BLANK] : [];
        var i, len, token;
        
        for (i = 0, len = src.length; i < len; ++i) {
            token = src[i] || BLANK;
            if (token === DOTS) {
                if (target.length > 1) {
                    target.pop();
                }
            } else if (token !== BLANK && token !== DOT) {
                target.push(token);
            }
        }

        return target.join(SLASH).replace(/[\/]{2, }/g, SLASH) || SLASH;
    };

    // test normalize
    
    if (!console) {
        return;
    }
    
    // should all print true
    
    console.warn(normalize('') === '/');
    console.warn(normalize('/') === '/');
    console.warn(normalize('//') === '/');
    console.warn(normalize('..') === '/');
    console.warn(normalize('.') === '/');

    console.warn(normalize('plain') === 'plain');
    console.warn(normalize('/slash') === '/slash');
    console.warn(normalize('./dot') === '/dot' );
    console.warn(normalize('../dots') === '/dots');
    console.warn(normalize('plain/embedded') === 'plain/embedded' );
    console.warn(normalize('./dot/embedded') === '/dot/embedded');
    console.warn(normalize('../../dots/embedded') === '/dots/embedded' );
    console.warn(normalize('../../../embedded') === '/embedded' );
    console.warn(normalize('../../../../../../../../long') === '/long');
    console.warn(normalize('/foo//bar/../baz////././../baz/spam', '/') === '/foo/baz/spam');
    console.warn(normalize('/top/../..//..//../../../bottom') === '/bottom');
    console.warn(normalize('/top/middle/../womp/../bottom') === '/top/bottom');
    
}(this));

UPDATE 2013-02-27 ~ This is now in the repo at https://github.com/dfkaye/simple-path-normalize