Make a new urllib package .

It consists of code from urllib, urllib2, urlparse, and robotparser.
The old modules have all been removed.  The new package has five
submodules: urllib.parse, urllib.request, urllib.response,
urllib.error, and urllib.robotparser.  The urllib.request.urlopen()
function uses the url opener from urllib2.

Note that the unittests have not been renamed for the
beta, but they will be renamed in the future.

Joint work with Senthil Kumaran.
diff --git a/Lib/urllib/parse.py b/Lib/urllib/parse.py
new file mode 100644
index 0000000..71cc369
--- /dev/null
+++ b/Lib/urllib/parse.py
@@ -0,0 +1,630 @@
+"""Parse (absolute and relative) URLs.
+
+See RFC 1808: "Relative Uniform Resource Locators", by R. Fielding,
+UC Irvine, June 1995.
+"""
+
+__all__ = ["urlparse", "urlunparse", "urljoin", "urldefrag",
+           "urlsplit", "urlunsplit"]
+
+# A classification of schemes ('' means apply by default)
+uses_relative = ['ftp', 'http', 'gopher', 'nntp', 'imap',
+                 'wais', 'file', 'https', 'shttp', 'mms',
+                 'prospero', 'rtsp', 'rtspu', '', 'sftp']
+uses_netloc = ['ftp', 'http', 'gopher', 'nntp', 'telnet',
+               'imap', 'wais', 'file', 'mms', 'https', 'shttp',
+               'snews', 'prospero', 'rtsp', 'rtspu', 'rsync', '',
+               'svn', 'svn+ssh', 'sftp']
+non_hierarchical = ['gopher', 'hdl', 'mailto', 'news',
+                    'telnet', 'wais', 'imap', 'snews', 'sip', 'sips']
+uses_params = ['ftp', 'hdl', 'prospero', 'http', 'imap',
+               'https', 'shttp', 'rtsp', 'rtspu', 'sip', 'sips',
+               'mms', '', 'sftp']
+uses_query = ['http', 'wais', 'imap', 'https', 'shttp', 'mms',
+              'gopher', 'rtsp', 'rtspu', 'sip', 'sips', '']
+uses_fragment = ['ftp', 'hdl', 'http', 'gopher', 'news',
+                 'nntp', 'wais', 'https', 'shttp', 'snews',
+                 'file', 'prospero', '']
+
+# Characters valid in scheme names
+scheme_chars = ('abcdefghijklmnopqrstuvwxyz'
+                'ABCDEFGHIJKLMNOPQRSTUVWXYZ'
+                '0123456789'
+                '+-.')
+
+MAX_CACHE_SIZE = 20
+_parse_cache = {}
+
+def clear_cache():
+    """Clear the parse cache."""
+    _parse_cache.clear()
+
+
+class ResultMixin(object):
+    """Shared methods for the parsed result objects."""
+
+    @property
+    def username(self):
+        netloc = self.netloc
+        if "@" in netloc:
+            userinfo = netloc.rsplit("@", 1)[0]
+            if ":" in userinfo:
+                userinfo = userinfo.split(":", 1)[0]
+            return userinfo
+        return None
+
+    @property
+    def password(self):
+        netloc = self.netloc
+        if "@" in netloc:
+            userinfo = netloc.rsplit("@", 1)[0]
+            if ":" in userinfo:
+                return userinfo.split(":", 1)[1]
+        return None
+
+    @property
+    def hostname(self):
+        netloc = self.netloc
+        if "@" in netloc:
+            netloc = netloc.rsplit("@", 1)[1]
+        if ":" in netloc:
+            netloc = netloc.split(":", 1)[0]
+        return netloc.lower() or None
+
+    @property
+    def port(self):
+        netloc = self.netloc
+        if "@" in netloc:
+            netloc = netloc.rsplit("@", 1)[1]
+        if ":" in netloc:
+            port = netloc.split(":", 1)[1]
+            return int(port, 10)
+        return None
+
+from collections import namedtuple
+
+class SplitResult(namedtuple('SplitResult', 'scheme netloc path query fragment'), ResultMixin):
+
+    __slots__ = ()
+
+    def geturl(self):
+        return urlunsplit(self)
+
+
+class ParseResult(namedtuple('ParseResult', 'scheme netloc path params query fragment'), ResultMixin):
+
+    __slots__ = ()
+
+    def geturl(self):
+        return urlunparse(self)
+
+
+def urlparse(url, scheme='', allow_fragments=True):
+    """Parse a URL into 6 components:
+    <scheme>://<netloc>/<path>;<params>?<query>#<fragment>
+    Return a 6-tuple: (scheme, netloc, path, params, query, fragment).
+    Note that we don't break the components up in smaller bits
+    (e.g. netloc is a single string) and we don't expand % escapes."""
+    tuple = urlsplit(url, scheme, allow_fragments)
+    scheme, netloc, url, query, fragment = tuple
+    if scheme in uses_params and ';' in url:
+        url, params = _splitparams(url)
+    else:
+        params = ''
+    return ParseResult(scheme, netloc, url, params, query, fragment)
+
+def _splitparams(url):
+    if '/'  in url:
+        i = url.find(';', url.rfind('/'))
+        if i < 0:
+            return url, ''
+    else:
+        i = url.find(';')
+    return url[:i], url[i+1:]
+
+def _splitnetloc(url, start=0):
+    delim = len(url)   # position of end of domain part of url, default is end
+    for c in '/?#':    # look for delimiters; the order is NOT important
+        wdelim = url.find(c, start)        # find first of this delim
+        if wdelim >= 0:                    # if found
+            delim = min(delim, wdelim)     # use earliest delim position
+    return url[start:delim], url[delim:]   # return (domain, rest)
+
+def urlsplit(url, scheme='', allow_fragments=True):
+    """Parse a URL into 5 components:
+    <scheme>://<netloc>/<path>?<query>#<fragment>
+    Return a 5-tuple: (scheme, netloc, path, query, fragment).
+    Note that we don't break the components up in smaller bits
+    (e.g. netloc is a single string) and we don't expand % escapes."""
+    allow_fragments = bool(allow_fragments)
+    key = url, scheme, allow_fragments, type(url), type(scheme)
+    cached = _parse_cache.get(key, None)
+    if cached:
+        return cached
+    if len(_parse_cache) >= MAX_CACHE_SIZE: # avoid runaway growth
+        clear_cache()
+    netloc = query = fragment = ''
+    i = url.find(':')
+    if i > 0:
+        if url[:i] == 'http': # optimize the common case
+            scheme = url[:i].lower()
+            url = url[i+1:]
+            if url[:2] == '//':
+                netloc, url = _splitnetloc(url, 2)
+            if allow_fragments and '#' in url:
+                url, fragment = url.split('#', 1)
+            if '?' in url:
+                url, query = url.split('?', 1)
+            v = SplitResult(scheme, netloc, url, query, fragment)
+            _parse_cache[key] = v
+            return v
+        for c in url[:i]:
+            if c not in scheme_chars:
+                break
+        else:
+            scheme, url = url[:i].lower(), url[i+1:]
+    if scheme in uses_netloc and url[:2] == '//':
+        netloc, url = _splitnetloc(url, 2)
+    if allow_fragments and scheme in uses_fragment and '#' in url:
+        url, fragment = url.split('#', 1)
+    if scheme in uses_query and '?' in url:
+        url, query = url.split('?', 1)
+    v = SplitResult(scheme, netloc, url, query, fragment)
+    _parse_cache[key] = v
+    return v
+
+def urlunparse(components):
+    """Put a parsed URL back together again.  This may result in a
+    slightly different, but equivalent URL, if the URL that was parsed
+    originally had redundant delimiters, e.g. a ? with an empty query
+    (the draft states that these are equivalent)."""
+    scheme, netloc, url, params, query, fragment = components
+    if params:
+        url = "%s;%s" % (url, params)
+    return urlunsplit((scheme, netloc, url, query, fragment))
+
+def urlunsplit(components):
+    scheme, netloc, url, query, fragment = components
+    if netloc or (scheme and scheme in uses_netloc and url[:2] != '//'):
+        if url and url[:1] != '/': url = '/' + url
+        url = '//' + (netloc or '') + url
+    if scheme:
+        url = scheme + ':' + url
+    if query:
+        url = url + '?' + query
+    if fragment:
+        url = url + '#' + fragment
+    return url
+
+def urljoin(base, url, allow_fragments=True):
+    """Join a base URL and a possibly relative URL to form an absolute
+    interpretation of the latter."""
+    if not base:
+        return url
+    if not url:
+        return base
+    bscheme, bnetloc, bpath, bparams, bquery, bfragment = \
+            urlparse(base, '', allow_fragments)
+    scheme, netloc, path, params, query, fragment = \
+            urlparse(url, bscheme, allow_fragments)
+    if scheme != bscheme or scheme not in uses_relative:
+        return url
+    if scheme in uses_netloc:
+        if netloc:
+            return urlunparse((scheme, netloc, path,
+                               params, query, fragment))
+        netloc = bnetloc
+    if path[:1] == '/':
+        return urlunparse((scheme, netloc, path,
+                           params, query, fragment))
+    if not (path or params or query):
+        return urlunparse((scheme, netloc, bpath,
+                           bparams, bquery, fragment))
+    segments = bpath.split('/')[:-1] + path.split('/')
+    # XXX The stuff below is bogus in various ways...
+    if segments[-1] == '.':
+        segments[-1] = ''
+    while '.' in segments:
+        segments.remove('.')
+    while 1:
+        i = 1
+        n = len(segments) - 1
+        while i < n:
+            if (segments[i] == '..'
+                and segments[i-1] not in ('', '..')):
+                del segments[i-1:i+1]
+                break
+            i = i+1
+        else:
+            break
+    if segments == ['', '..']:
+        segments[-1] = ''
+    elif len(segments) >= 2 and segments[-1] == '..':
+        segments[-2:] = ['']
+    return urlunparse((scheme, netloc, '/'.join(segments),
+                       params, query, fragment))
+
+def urldefrag(url):
+    """Removes any existing fragment from URL.
+
+    Returns a tuple of the defragmented URL and the fragment.  If
+    the URL contained no fragments, the second element is the
+    empty string.
+    """
+    if '#' in url:
+        s, n, p, a, q, frag = urlparse(url)
+        defrag = urlunparse((s, n, p, a, q, ''))
+        return defrag, frag
+    else:
+        return url, ''
+
+
+_hextochr = dict(('%02x' % i, chr(i)) for i in range(256))
+_hextochr.update(('%02X' % i, chr(i)) for i in range(256))
+
+def unquote(s):
+    """unquote('abc%20def') -> 'abc def'."""
+    res = s.split('%')
+    for i in range(1, len(res)):
+        item = res[i]
+        try:
+            res[i] = _hextochr[item[:2]] + item[2:]
+        except KeyError:
+            res[i] = '%' + item
+        except UnicodeDecodeError:
+            res[i] = chr(int(item[:2], 16)) + item[2:]
+    return "".join(res)
+
+def unquote_plus(s):
+    """unquote('%7e/abc+def') -> '~/abc def'"""
+    s = s.replace('+', ' ')
+    return unquote(s)
+
+always_safe = ('ABCDEFGHIJKLMNOPQRSTUVWXYZ'
+               'abcdefghijklmnopqrstuvwxyz'
+               '0123456789' '_.-')
+_safe_quoters= {}
+
+class Quoter:
+    def __init__(self, safe):
+        self.cache = {}
+        self.safe = safe + always_safe
+
+    def __call__(self, c):
+        try:
+            return self.cache[c]
+        except KeyError:
+            if ord(c) < 256:
+                res = (c in self.safe) and c or ('%%%02X' % ord(c))
+                self.cache[c] = res
+                return res
+            else:
+                return "".join(['%%%02X' % i for i in c.encode("utf-8")])
+
+def quote(s, safe = '/'):
+    """quote('abc def') -> 'abc%20def'
+
+    Each part of a URL, e.g. the path info, the query, etc., has a
+    different set of reserved characters that must be quoted.
+
+    RFC 2396 Uniform Resource Identifiers (URI): Generic Syntax lists
+    the following reserved characters.
+
+    reserved    = ";" | "/" | "?" | ":" | "@" | "&" | "=" | "+" |
+                  "$" | ","
+
+    Each of these characters is reserved in some component of a URL,
+    but not necessarily in all of them.
+
+    By default, the quote function is intended for quoting the path
+    section of a URL.  Thus, it will not encode '/'.  This character
+    is reserved, but in typical usage the quote function is being
+    called on a path where the existing slash characters are used as
+    reserved characters.
+    """
+    cachekey = (safe, always_safe)
+    try:
+        quoter = _safe_quoters[cachekey]
+    except KeyError:
+        quoter = Quoter(safe)
+        _safe_quoters[cachekey] = quoter
+    res = map(quoter, s)
+    return ''.join(res)
+
+def quote_plus(s, safe = ''):
+    """Quote the query fragment of a URL; replacing ' ' with '+'"""
+    if ' ' in s:
+        s = quote(s, safe + ' ')
+        return s.replace(' ', '+')
+    return quote(s, safe)
+
+def urlencode(query,doseq=0):
+    """Encode a sequence of two-element tuples or dictionary into a URL query string.
+
+    If any values in the query arg are sequences and doseq is true, each
+    sequence element is converted to a separate parameter.
+
+    If the query arg is a sequence of two-element tuples, the order of the
+    parameters in the output will match the order of parameters in the
+    input.
+    """
+
+    if hasattr(query,"items"):
+        # mapping objects
+        query = query.items()
+    else:
+        # it's a bother at times that strings and string-like objects are
+        # sequences...
+        try:
+            # non-sequence items should not work with len()
+            # non-empty strings will fail this
+            if len(query) and not isinstance(query[0], tuple):
+                raise TypeError
+            # zero-length sequences of all types will get here and succeed,
+            # but that's a minor nit - since the original implementation
+            # allowed empty dicts that type of behavior probably should be
+            # preserved for consistency
+        except TypeError:
+            ty,va,tb = sys.exc_info()
+            raise TypeError("not a valid non-string sequence or mapping object").with_traceback(tb)
+
+    l = []
+    if not doseq:
+        # preserve old behavior
+        for k, v in query:
+            k = quote_plus(str(k))
+            v = quote_plus(str(v))
+            l.append(k + '=' + v)
+    else:
+        for k, v in query:
+            k = quote_plus(str(k))
+            if isinstance(v, str):
+                v = quote_plus(v)
+                l.append(k + '=' + v)
+            elif isinstance(v, str):
+                # is there a reasonable way to convert to ASCII?
+                # encode generates a string, but "replace" or "ignore"
+                # lose information and "strict" can raise UnicodeError
+                v = quote_plus(v.encode("ASCII","replace"))
+                l.append(k + '=' + v)
+            else:
+                try:
+                    # is this a sufficient test for sequence-ness?
+                    x = len(v)
+                except TypeError:
+                    # not a sequence
+                    v = quote_plus(str(v))
+                    l.append(k + '=' + v)
+                else:
+                    # loop over the sequence
+                    for elt in v:
+                        l.append(k + '=' + quote_plus(str(elt)))
+    return '&'.join(l)
+
+# Utilities to parse URLs (most of these return None for missing parts):
+# unwrap('<URL:type://host/path>') --> 'type://host/path'
+# splittype('type:opaquestring') --> 'type', 'opaquestring'
+# splithost('//host[:port]/path') --> 'host[:port]', '/path'
+# splituser('user[:passwd]@host[:port]') --> 'user[:passwd]', 'host[:port]'
+# splitpasswd('user:passwd') -> 'user', 'passwd'
+# splitport('host:port') --> 'host', 'port'
+# splitquery('/path?query') --> '/path', 'query'
+# splittag('/path#tag') --> '/path', 'tag'
+# splitattr('/path;attr1=value1;attr2=value2;...') ->
+#   '/path', ['attr1=value1', 'attr2=value2', ...]
+# splitvalue('attr=value') --> 'attr', 'value'
+# urllib.parse.unquote('abc%20def') -> 'abc def'
+# quote('abc def') -> 'abc%20def')
+
+def toBytes(url):
+    """toBytes(u"URL") --> 'URL'."""
+    # Most URL schemes require ASCII. If that changes, the conversion
+    # can be relaxed.
+    # XXX get rid of toBytes()
+    if isinstance(url, str):
+        try:
+            url = url.encode("ASCII").decode()
+        except UnicodeError:
+            raise UnicodeError("URL " + repr(url) +
+                               " contains non-ASCII characters")
+    return url
+
+def unwrap(url):
+    """unwrap('<URL:type://host/path>') --> 'type://host/path'."""
+    url = str(url).strip()
+    if url[:1] == '<' and url[-1:] == '>':
+        url = url[1:-1].strip()
+    if url[:4] == 'URL:': url = url[4:].strip()
+    return url
+
+_typeprog = None
+def splittype(url):
+    """splittype('type:opaquestring') --> 'type', 'opaquestring'."""
+    global _typeprog
+    if _typeprog is None:
+        import re
+        _typeprog = re.compile('^([^/:]+):')
+
+    match = _typeprog.match(url)
+    if match:
+        scheme = match.group(1)
+        return scheme.lower(), url[len(scheme) + 1:]
+    return None, url
+
+_hostprog = None
+def splithost(url):
+    """splithost('//host[:port]/path') --> 'host[:port]', '/path'."""
+    global _hostprog
+    if _hostprog is None:
+        import re
+        _hostprog = re.compile('^//([^/?]*)(.*)$')
+
+    match = _hostprog.match(url)
+    if match: return match.group(1, 2)
+    return None, url
+
+_userprog = None
+def splituser(host):
+    """splituser('user[:passwd]@host[:port]') --> 'user[:passwd]', 'host[:port]'."""
+    global _userprog
+    if _userprog is None:
+        import re
+        _userprog = re.compile('^(.*)@(.*)$')
+
+    match = _userprog.match(host)
+    if match: return map(unquote, match.group(1, 2))
+    return None, host
+
+_passwdprog = None
+def splitpasswd(user):
+    """splitpasswd('user:passwd') -> 'user', 'passwd'."""
+    global _passwdprog
+    if _passwdprog is None:
+        import re
+        _passwdprog = re.compile('^([^:]*):(.*)$')
+
+    match = _passwdprog.match(user)
+    if match: return match.group(1, 2)
+    return user, None
+
+# splittag('/path#tag') --> '/path', 'tag'
+_portprog = None
+def splitport(host):
+    """splitport('host:port') --> 'host', 'port'."""
+    global _portprog
+    if _portprog is None:
+        import re
+        _portprog = re.compile('^(.*):([0-9]+)$')
+
+    match = _portprog.match(host)
+    if match: return match.group(1, 2)
+    return host, None
+
+_nportprog = None
+def splitnport(host, defport=-1):
+    """Split host and port, returning numeric port.
+    Return given default port if no ':' found; defaults to -1.
+    Return numerical port if a valid number are found after ':'.
+    Return None if ':' but not a valid number."""
+    global _nportprog
+    if _nportprog is None:
+        import re
+        _nportprog = re.compile('^(.*):(.*)$')
+
+    match = _nportprog.match(host)
+    if match:
+        host, port = match.group(1, 2)
+        try:
+            if not port: raise ValueError("no digits")
+            nport = int(port)
+        except ValueError:
+            nport = None
+        return host, nport
+    return host, defport
+
+_queryprog = None
+def splitquery(url):
+    """splitquery('/path?query') --> '/path', 'query'."""
+    global _queryprog
+    if _queryprog is None:
+        import re
+        _queryprog = re.compile('^(.*)\?([^?]*)$')
+
+    match = _queryprog.match(url)
+    if match: return match.group(1, 2)
+    return url, None
+
+_tagprog = None
+def splittag(url):
+    """splittag('/path#tag') --> '/path', 'tag'."""
+    global _tagprog
+    if _tagprog is None:
+        import re
+        _tagprog = re.compile('^(.*)#([^#]*)$')
+
+    match = _tagprog.match(url)
+    if match: return match.group(1, 2)
+    return url, None
+
+def splitattr(url):
+    """splitattr('/path;attr1=value1;attr2=value2;...') ->
+        '/path', ['attr1=value1', 'attr2=value2', ...]."""
+    words = url.split(';')
+    return words[0], words[1:]
+
+_valueprog = None
+def splitvalue(attr):
+    """splitvalue('attr=value') --> 'attr', 'value'."""
+    global _valueprog
+    if _valueprog is None:
+        import re
+        _valueprog = re.compile('^([^=]*)=(.*)$')
+
+    match = _valueprog.match(attr)
+    if match: return match.group(1, 2)
+    return attr, None
+
+test_input = """
+      http://a/b/c/d
+
+      g:h        = <URL:g:h>
+      http:g     = <URL:http://a/b/c/g>
+      http:      = <URL:http://a/b/c/d>
+      g          = <URL:http://a/b/c/g>
+      ./g        = <URL:http://a/b/c/g>
+      g/         = <URL:http://a/b/c/g/>
+      /g         = <URL:http://a/g>
+      //g        = <URL:http://g>
+      ?y         = <URL:http://a/b/c/d?y>
+      g?y        = <URL:http://a/b/c/g?y>
+      g?y/./x    = <URL:http://a/b/c/g?y/./x>
+      .          = <URL:http://a/b/c/>
+      ./         = <URL:http://a/b/c/>
+      ..         = <URL:http://a/b/>
+      ../        = <URL:http://a/b/>
+      ../g       = <URL:http://a/b/g>
+      ../..      = <URL:http://a/>
+      ../../g    = <URL:http://a/g>
+      ../../../g = <URL:http://a/../g>
+      ./../g     = <URL:http://a/b/g>
+      ./g/.      = <URL:http://a/b/c/g/>
+      /./g       = <URL:http://a/./g>
+      g/./h      = <URL:http://a/b/c/g/h>
+      g/../h     = <URL:http://a/b/c/h>
+      http:g     = <URL:http://a/b/c/g>
+      http:      = <URL:http://a/b/c/d>
+      http:?y         = <URL:http://a/b/c/d?y>
+      http:g?y        = <URL:http://a/b/c/g?y>
+      http:g?y/./x    = <URL:http://a/b/c/g?y/./x>
+"""
+
+def test():
+    import sys
+    base = ''
+    if sys.argv[1:]:
+        fn = sys.argv[1]
+        if fn == '-':
+            fp = sys.stdin
+        else:
+            fp = open(fn)
+    else:
+        from io import StringIO
+        fp = StringIO(test_input)
+    for line in fp:
+        words = line.split()
+        if not words:
+            continue
+        url = words[0]
+        parts = urlparse(url)
+        print('%-10s : %s' % (url, parts))
+        abs = urljoin(base, url)
+        if not base:
+            base = abs
+        wrapped = '<URL:%s>' % abs
+        print('%-10s = %s' % (url, wrapped))
+        if len(words) == 3 and words[1] == '=':
+            if wrapped != words[2]:
+                print('EXPECTED', words[2], '!!!!!!!!!!')
+
+if __name__ == '__main__':
+    test()