[py3] Bundled six for Python 3 compatibility.

Refs #18363.

2 files changed, 353 insertions, 109 deletions

diff --git a/django/utils/py3.py b/django/utils/py3.py
deleted file mode 100644
index 8a5c37e976..0000000000
--- a/django/utils/py3.py
+++ /dev/null
@@ -1,109 +0,0 @@
-# Compatibility layer for running Django both in 2.x and 3.x
-
-import sys
-
-if sys.version_info[0] < 3:
-    PY3 = False
-    # Changed module locations
-    from urlparse import (urlparse, urlunparse, urljoin, urlsplit, urlunsplit,
-                          urldefrag, parse_qsl)
-    from urllib import (quote, unquote, quote_plus, urlopen, urlencode,
-                        url2pathname, urlretrieve, unquote_plus)
-    from urllib2 import (Request, OpenerDirector, UnknownHandler, HTTPHandler,
-                         HTTPSHandler, HTTPDefaultErrorHandler, FTPHandler,
-                         HTTPError, HTTPErrorProcessor)
-    import urllib2
-    import Cookie as cookies
-    try:
-        import cPickle as pickle
-    except ImportError:
-        import pickle
-    try:
-        import thread
-    except ImportError:
-        import dummy_thread as thread
-    from htmlentitydefs import name2codepoint
-    import HTMLParser
-    from os import getcwdu
-    from itertools import izip as zip
-    unichr = unichr
-    xrange = xrange
-    maxsize = sys.maxint
-
-    # Type aliases
-    string_types = basestring,
-    text_type = unicode
-    integer_types = int, long
-    long_type = long
-
-    from io import BytesIO as OutputIO
-
-    # Glue code for syntax differences
-    def reraise(tp, value, tb=None):
-        exec("raise tp, value, tb")
-
-    def with_metaclass(meta, base=object):
-        class _DjangoBase(base):
-            __metaclass__ = meta
-        return _DjangoBase
-
-    iteritems = lambda o: o.iteritems()
-    itervalues = lambda o: o.itervalues()
-    iterkeys = lambda o: o.iterkeys()
-
-    # n() is useful when python3 needs a str (unicode), and python2 str (bytes)
-    n = lambda s: s.encode('utf-8')
-
-else:
-    PY3 = True
-    import builtins
-
-    # Changed module locations
-    from urllib.parse import (urlparse, urlunparse, urlencode, urljoin,
-                              urlsplit, urlunsplit, quote, unquote,
-                              quote_plus, unquote_plus, parse_qsl,
-                              urldefrag)
-    from urllib.request import (urlopen, url2pathname, Request, OpenerDirector,
-                                UnknownHandler, HTTPHandler, HTTPSHandler,
-                                HTTPDefaultErrorHandler, FTPHandler,
-                                HTTPError, HTTPErrorProcessor, urlretrieve)
-    import urllib.request as urllib2
-    import http.cookies as cookies
-    import pickle
-    try:
-        import _thread as thread
-    except ImportError:
-        import _dummy_thread as thread
-    from html.entities import name2codepoint
-    import html.parser as HTMLParser
-    from os import getcwd as getcwdu
-    zip = zip
-    unichr = chr
-    xrange = range
-    maxsize = sys.maxsize
-
-    # Type aliases
-    string_types = str,
-    text_type = str
-    integer_types = int,
-    long_type = int
-
-    from io import StringIO as OutputIO
-
-    # Glue code for syntax differences
-    def reraise(tp, value, tb=None):
-        if value.__traceback__ is not tb:
-            raise value.with_traceback(tb)
-        raise value
-
-    def with_metaclass(meta, base=object):
-        ns = dict(base=base, meta=meta)
-        exec("""class _DjangoBase(base, metaclass=meta):
-    pass""", ns)
-        return ns["_DjangoBase"]
-
-    iteritems = lambda o: o.items()
-    itervalues = lambda o: o.values()
-    iterkeys = lambda o: o.keys()
-
-    n = lambda s: s
diff --git a/django/utils/six.py b/django/utils/six.py
new file mode 100644
index 0000000000..6526d76cb1
--- /dev/null
+++ b/django/utils/six.py
@@ -0,0 +1,353 @@
+"""Utilities for writing code that runs on Python 2 and 3"""
+
+import operator
+import sys
+import types
+
+__author__ = "Benjamin Peterson <benjamin@python.org>"
+__version__ = "1.1.0"
+
+
+# True if we are running on Python 3.
+PY3 = sys.version_info[0] == 3
+
+if PY3:
+    string_types = str,
+    integer_types = int,
+    class_types = type,
+    text_type = str
+    binary_type = bytes
+
+    MAXSIZE = sys.maxsize
+else:
+    string_types = basestring,
+    integer_types = (int, long)
+    class_types = (type, types.ClassType)
+    text_type = unicode
+    binary_type = str
+
+    # It's possible to have sizeof(long) != sizeof(Py_ssize_t).
+    class X(object):
+        def __len__(self):
+            return 1 << 31
+    try:
+        len(X())
+    except OverflowError:
+        # 32-bit
+        MAXSIZE = int((1 << 31) - 1)
+    else:
+        # 64-bit
+        MAXSIZE = int((1 << 63) - 1)
+    del X
+
+
+def _add_doc(func, doc):
+    """Add documentation to a function."""
+    func.__doc__ = doc
+
+
+def _import_module(name):
+    """Import module, returning the module after the last dot."""
+    __import__(name)
+    return sys.modules[name]
+
+
+class _LazyDescr(object):
+
+    def __init__(self, name):
+        self.name = name
+
+    def __get__(self, obj, tp):
+        result = self._resolve()
+        setattr(obj, self.name, result)
+        # This is a bit ugly, but it avoids running this again.
+        delattr(tp, self.name)
+        return result
+
+
+class MovedModule(_LazyDescr):
+
+    def __init__(self, name, old, new=None):
+        super(MovedModule, self).__init__(name)
+        if PY3:
+            if new is None:
+                new = name
+            self.mod = new
+        else:
+            self.mod = old
+
+    def _resolve(self):
+        return _import_module(self.mod)
+
+
+class MovedAttribute(_LazyDescr):
+
+    def __init__(self, name, old_mod, new_mod, old_attr=None, new_attr=None):
+        super(MovedAttribute, self).__init__(name)
+        if PY3:
+            if new_mod is None:
+                new_mod = name
+            self.mod = new_mod
+            if new_attr is None:
+                if old_attr is None:
+                    new_attr = name
+                else:
+                    new_attr = old_attr
+            self.attr = new_attr
+        else:
+            self.mod = old_mod
+            if old_attr is None:
+                old_attr = name
+            self.attr = old_attr
+
+    def _resolve(self):
+        module = _import_module(self.mod)
+        return getattr(module, self.attr)
+
+
+
+class _MovedItems(types.ModuleType):
+    """Lazy loading of moved objects"""
+
+
+_moved_attributes = [
+    MovedAttribute("cStringIO", "cStringIO", "io", "StringIO"),
+    MovedAttribute("filter", "itertools", "builtins", "ifilter", "filter"),
+    MovedAttribute("map", "itertools", "builtins", "imap", "map"),
+    MovedAttribute("reload_module", "__builtin__", "imp", "reload"),
+    MovedAttribute("reduce", "__builtin__", "functools"),
+    MovedAttribute("StringIO", "StringIO", "io"),
+    MovedAttribute("xrange", "__builtin__", "builtins", "xrange", "range"),
+    MovedAttribute("zip", "itertools", "builtins", "izip", "zip"),
+
+    MovedModule("builtins", "__builtin__"),
+    MovedModule("configparser", "ConfigParser"),
+    MovedModule("copyreg", "copy_reg"),
+    MovedModule("http_cookiejar", "cookielib", "http.cookiejar"),
+    MovedModule("http_cookies", "Cookie", "http.cookies"),
+    MovedModule("html_entities", "htmlentitydefs", "html.entities"),
+    MovedModule("html_parser", "HTMLParser", "html.parser"),
+    MovedModule("http_client", "httplib", "http.client"),
+    MovedModule("BaseHTTPServer", "BaseHTTPServer", "http.server"),
+    MovedModule("CGIHTTPServer", "CGIHTTPServer", "http.server"),
+    MovedModule("SimpleHTTPServer", "SimpleHTTPServer", "http.server"),
+    MovedModule("cPickle", "cPickle", "pickle"),
+    MovedModule("queue", "Queue"),
+    MovedModule("reprlib", "repr"),
+    MovedModule("socketserver", "SocketServer"),
+    MovedModule("tkinter", "Tkinter"),
+    MovedModule("tkinter_dialog", "Dialog", "tkinter.dialog"),
+    MovedModule("tkinter_filedialog", "FileDialog", "tkinter.filedialog"),
+    MovedModule("tkinter_scrolledtext", "ScrolledText", "tkinter.scrolledtext"),
+    MovedModule("tkinter_simpledialog", "SimpleDialog", "tkinter.simpledialog"),
+    MovedModule("tkinter_tix", "Tix", "tkinter.tix"),
+    MovedModule("tkinter_constants", "Tkconstants", "tkinter.constants"),
+    MovedModule("tkinter_dnd", "Tkdnd", "tkinter.dnd"),
+    MovedModule("tkinter_colorchooser", "tkColorChooser",
+                "tkinter.colorchooser"),
+    MovedModule("tkinter_commondialog", "tkCommonDialog",
+                "tkinter.commondialog"),
+    MovedModule("tkinter_tkfiledialog", "tkFileDialog", "tkinter.filedialog"),
+    MovedModule("tkinter_font", "tkFont", "tkinter.font"),
+    MovedModule("tkinter_messagebox", "tkMessageBox", "tkinter.messagebox"),
+    MovedModule("tkinter_tksimpledialog", "tkSimpleDialog",
+                "tkinter.simpledialog"),
+    MovedModule("urllib_robotparser", "robotparser", "urllib.robotparser"),
+    MovedModule("winreg", "_winreg"),
+]
+for attr in _moved_attributes:
+    setattr(_MovedItems, attr.name, attr)
+del attr
+
+moves = sys.modules["six.moves"] = _MovedItems("moves")
+
+
+def add_move(move):
+    """Add an item to six.moves."""
+    setattr(_MovedItems, move.name, move)
+
+
+def remove_move(name):
+    """Remove item from six.moves."""
+    try:
+        delattr(_MovedItems, name)
+    except AttributeError:
+        try:
+            del moves.__dict__[name]
+        except KeyError:
+            raise AttributeError("no such move, %r" % (name,))
+
+
+if PY3:
+    _meth_func = "__func__"
+    _meth_self = "__self__"
+
+    _func_code = "__code__"
+    _func_defaults = "__defaults__"
+
+    _iterkeys = "keys"
+    _itervalues = "values"
+    _iteritems = "items"
+else:
+    _meth_func = "im_func"
+    _meth_self = "im_self"
+
+    _func_code = "func_code"
+    _func_defaults = "func_defaults"
+
+    _iterkeys = "iterkeys"
+    _itervalues = "itervalues"
+    _iteritems = "iteritems"
+
+
+if PY3:
+    def get_unbound_function(unbound):
+        return unbound
+
+
+    advance_iterator = next
+
+    def callable(obj):
+        return any("__call__" in klass.__dict__ for klass in type(obj).__mro__)
+else:
+    def get_unbound_function(unbound):
+        return unbound.im_func
+
+
+    def advance_iterator(it):
+        return it.next()
+
+    callable = callable
+_add_doc(get_unbound_function,
+         """Get the function out of a possibly unbound function""")
+
+
+get_method_function = operator.attrgetter(_meth_func)
+get_method_self = operator.attrgetter(_meth_self)
+get_function_code = operator.attrgetter(_func_code)
+get_function_defaults = operator.attrgetter(_func_defaults)
+
+
+def iterkeys(d):
+    """Return an iterator over the keys of a dictionary."""
+    return getattr(d, _iterkeys)()
+
+def itervalues(d):
+    """Return an iterator over the values of a dictionary."""
+    return getattr(d, _itervalues)()
+
+def iteritems(d):
+    """Return an iterator over the (key, value) pairs of a dictionary."""
+    return getattr(d, _iteritems)()
+
+
+if PY3:
+    def b(s):
+        return s.encode("latin-1")
+    def u(s):
+        return s
+    if sys.version_info[1] <= 1:
+        def int2byte(i):
+            return bytes((i,))
+    else:
+        # This is about 2x faster than the implementation above on 3.2+
+        int2byte = operator.methodcaller("to_bytes", 1, "big")
+    import io
+    StringIO = io.StringIO
+    BytesIO = io.BytesIO
+else:
+    def b(s):
+        return s
+    def u(s):
+        return unicode(s, "unicode_escape")
+    int2byte = chr
+    import StringIO
+    StringIO = BytesIO = StringIO.StringIO
+_add_doc(b, """Byte literal""")
+_add_doc(u, """Text literal""")
+
+
+if PY3:
+    import builtins
+    exec_ = getattr(builtins, "exec")
+
+
+    def reraise(tp, value, tb=None):
+        if value.__traceback__ is not tb:
+            raise value.with_traceback(tb)
+        raise value
+
+
+    print_ = getattr(builtins, "print")
+    del builtins
+
+else:
+    def exec_(code, globs=None, locs=None):
+        """Execute code in a namespace."""
+        if globs is None:
+            frame = sys._getframe(1)
+            globs = frame.f_globals
+            if locs is None:
+                locs = frame.f_locals
+            del frame
+        elif locs is None:
+            locs = globs
+        exec("""exec code in globs, locs""")
+
+
+    exec_("""def reraise(tp, value, tb=None):
+    raise tp, value, tb
+""")
+
+
+    def print_(*args, **kwargs):
+        """The new-style print function."""
+        fp = kwargs.pop("file", sys.stdout)
+        if fp is None:
+            return
+        def write(data):
+            if not isinstance(data, basestring):
+                data = str(data)
+            fp.write(data)
+        want_unicode = False
+        sep = kwargs.pop("sep", None)
+        if sep is not None:
+            if isinstance(sep, unicode):
+                want_unicode = True
+            elif not isinstance(sep, str):
+                raise TypeError("sep must be None or a string")
+        end = kwargs.pop("end", None)
+        if end is not None:
+            if isinstance(end, unicode):
+                want_unicode = True
+            elif not isinstance(end, str):
+                raise TypeError("end must be None or a string")
+        if kwargs:
+            raise TypeError("invalid keyword arguments to print()")
+        if not want_unicode:
+            for arg in args:
+                if isinstance(arg, unicode):
+                    want_unicode = True
+                    break
+        if want_unicode:
+            newline = unicode("\n")
+            space = unicode(" ")
+        else:
+            newline = "\n"
+            space = " "
+        if sep is None:
+            sep = space
+        if end is None:
+            end = newline
+        for i, arg in enumerate(args):
+            if i:
+                write(sep)
+            write(arg)
+        write(end)
+
+_add_doc(reraise, """Reraise an exception.""")
+
+
+def with_metaclass(meta, base=object):
+    """Create a base class with a metaclass."""
+    return meta("NewBase", (base,), {})