Upgraded some embedded dependencies to be ready for Python 3.10. This doesn't mean that it's fully supported right now.

24 files changed, 240 insertions, 78 deletions

diff --git a/libs/future/__init__.py b/libs/future/__init__.py
index 211fb43bc..ad419d67e 100644
--- a/libs/future/__init__.py
+++ b/libs/future/__init__.py
@@ -68,7 +68,7 @@ See: http://python-future.org
 Credits
 -------
 
-:Author:  Ed Schofield
+:Author:  Ed Schofield, Jordan M. Adler, et al
 :Sponsor: Python Charmers Pty Ltd, Australia, and Python Charmers Pte
           Ltd, Singapore. http://pythoncharmers.com
 :Others:  See docs/credits.rst or http://python-future.org/credits.html
@@ -76,7 +76,7 @@ Credits
 
 Licensing
 ---------
-Copyright 2013-2018 Python Charmers Pty Ltd, Australia.
+Copyright 2013-2019 Python Charmers Pty Ltd, Australia.
 The software is distributed under an MIT licence. See LICENSE.txt.
 
 """
@@ -84,10 +84,10 @@ The software is distributed under an MIT licence. See LICENSE.txt.
 __title__ = 'future'
 __author__ = 'Ed Schofield'
 __license__ = 'MIT'
-__copyright__ = 'Copyright 2013-2018 Python Charmers Pty Ltd'
+__copyright__ = 'Copyright 2013-2019 Python Charmers Pty Ltd'
 __ver_major__ = 0
-__ver_minor__ = 17
-__ver_patch__ = 0
+__ver_minor__ = 18
+__ver_patch__ = 2
 __ver_sub__ = ''
 __version__ = "%d.%d.%d%s" % (__ver_major__, __ver_minor__,
                               __ver_patch__, __ver_sub__)
diff --git a/libs/future/backports/__init__.py b/libs/future/backports/__init__.py
index 68291141c..c71e06535 100644
--- a/libs/future/backports/__init__.py
+++ b/libs/future/backports/__init__.py
@@ -10,7 +10,7 @@ __future_module__ = True
 from future.standard_library import import_top_level_modules
 
 
-if sys.version_info[0] == 3:
+if sys.version_info[0] >= 3:
     import_top_level_modules()
 
 
diff --git a/libs/future/backports/email/message.py b/libs/future/backports/email/message.py
index 99715fcc6..d8d9615d7 100644
--- a/libs/future/backports/email/message.py
+++ b/libs/future/backports/email/message.py
@@ -800,7 +800,7 @@ class Message(object):
             # There was no Content-Type header, and we don't know what type
             # to set it to, so raise an exception.
             raise errors.HeaderParseError('No Content-Type header found')
-        newparams = []
+        newparams = list()
         foundp = False
         for pk, pv in params:
             if pk.lower() == 'boundary':
@@ -814,10 +814,10 @@ class Message(object):
             # instead???
             newparams.append(('boundary', '"%s"' % boundary))
         # Replace the existing Content-Type header with the new value
-        newheaders = []
+        newheaders = list()
         for h, v in self._headers:
             if h.lower() == 'content-type':
-                parts = []
+                parts = list()
                 for k, v in newparams:
                     if v == '':
                         parts.append(k)
diff --git a/libs/future/backports/http/client.py b/libs/future/backports/http/client.py
index 5dd983d80..e663d125c 100644
--- a/libs/future/backports/http/client.py
+++ b/libs/future/backports/http/client.py
@@ -79,11 +79,15 @@ from future.backports.misc import create_connection as socket_create_connection
 import io
 import os
 import socket
-import collections
 from future.backports.urllib.parse import urlsplit
 import warnings
 from array import array
 
+if PY2:
+    from collections import Iterable
+else:
+    from collections.abc import Iterable
+
 __all__ = ["HTTPResponse", "HTTPConnection",
            "HTTPException", "NotConnected", "UnknownProtocol",
            "UnknownTransferEncoding", "UnimplementedFileMode",
@@ -696,9 +700,19 @@ class HTTPResponse(io.RawIOBase):
         while total_bytes < len(b):
             if MAXAMOUNT < len(mvb):
                 temp_mvb = mvb[0:MAXAMOUNT]
-                n = self.fp.readinto(temp_mvb)
+                if PY2:
+                    data = self.fp.read(len(temp_mvb))
+                    n = len(data)
+                    temp_mvb[:n] = data
+                else:
+                    n = self.fp.readinto(temp_mvb)
             else:
-                n = self.fp.readinto(mvb)
+                if PY2:
+                    data = self.fp.read(len(mvb))
+                    n = len(data)
+                    mvb[:n] = data
+                else:
+                    n = self.fp.readinto(mvb)
             if not n:
                 raise IncompleteRead(bytes(mvb[0:total_bytes]), len(b))
             mvb = mvb[n:]
@@ -892,7 +906,7 @@ class HTTPConnection(object):
         try:
             self.sock.sendall(data)
         except TypeError:
-            if isinstance(data, collections.Iterable):
+            if isinstance(data, Iterable):
                 for d in data:
                     self.sock.sendall(d)
             else:
diff --git a/libs/future/backports/http/cookiejar.py b/libs/future/backports/http/cookiejar.py
index cad72f9b4..af3ef4151 100644
--- a/libs/future/backports/http/cookiejar.py
+++ b/libs/future/backports/http/cookiejar.py
@@ -33,7 +33,7 @@ from __future__ import print_function
 from __future__ import division
 from __future__ import absolute_import
 from future.builtins import filter, int, map, open, str
-from future.utils import as_native_str
+from future.utils import as_native_str, PY2
 
 __all__ = ['Cookie', 'CookieJar', 'CookiePolicy', 'DefaultCookiePolicy',
            'FileCookieJar', 'LWPCookieJar', 'LoadError', 'MozillaCookieJar']
@@ -41,7 +41,8 @@ __all__ = ['Cookie', 'CookieJar', 'CookiePolicy', 'DefaultCookiePolicy',
 import copy
 import datetime
 import re
-re.ASCII = 0
+if PY2:
+    re.ASCII = 0
 import time
 from future.backports.urllib.parse import urlparse, urlsplit, quote
 from future.backports.http.client import HTTP_PORT
diff --git a/libs/future/backports/http/cookies.py b/libs/future/backports/http/cookies.py
index ae32ed7e7..8bb61e22c 100644
--- a/libs/future/backports/http/cookies.py
+++ b/libs/future/backports/http/cookies.py
@@ -138,7 +138,8 @@ from future.utils import PY2, as_native_str
 # Import our required modules
 #
 import re
-re.ASCII = 0    # for py2 compatibility
+if PY2:
+    re.ASCII = 0    # for py2 compatibility
 import string
 
 __all__ = ["CookieError", "BaseCookie", "SimpleCookie"]
diff --git a/libs/future/backports/misc.py b/libs/future/backports/misc.py
index ef7520788..098a0667e 100644
--- a/libs/future/backports/misc.py
+++ b/libs/future/backports/misc.py
@@ -16,7 +16,6 @@ from __future__ import absolute_import
 
 import subprocess
 from math import ceil as oldceil
-from collections import Mapping, MutableMapping
 
 from operator import itemgetter as _itemgetter, eq as _eq
 import sys
@@ -25,7 +24,12 @@ from _weakref import proxy as _proxy
 from itertools import repeat as _repeat, chain as _chain, starmap as _starmap
 from socket import getaddrinfo, SOCK_STREAM, error, socket
 
-from future.utils import iteritems, itervalues, PY26, PY3
+from future.utils import iteritems, itervalues, PY2, PY26, PY3
+
+if PY2:
+    from collections import Mapping, MutableMapping
+else:
+    from collections.abc import Mapping, MutableMapping
 
 
 def ceil(x):
diff --git a/libs/future/backports/test/pystone.py b/libs/future/backports/test/pystone.py
index 7652027b4..7652027b4 100644..100755
--- a/libs/future/backports/test/pystone.py
+++ b/libs/future/backports/test/pystone.py
diff --git a/libs/future/backports/urllib/request.py b/libs/future/backports/urllib/request.py
index b1545ca0f..baee5401a 100644
--- a/libs/future/backports/urllib/request.py
+++ b/libs/future/backports/urllib/request.py
@@ -109,11 +109,17 @@ import re
 import socket
 import sys
 import time
-import collections
 import tempfile
 import contextlib
 import warnings
 
+from future.utils import PY2
+
+if PY2:
+    from collections import Iterable
+else:
+    from collections.abc import Iterable
+
 # check for SSL
 try:
     import ssl
@@ -1221,7 +1227,7 @@ class AbstractHTTPHandler(BaseHandler):
                         mv = memoryview(data)
                         size = len(mv) * mv.itemsize
                 except TypeError:
-                    if isinstance(data, collections.Iterable):
+                    if isinstance(data, Iterable):
                         raise ValueError("Content-Length should be specified "
                                 "for iterable data of type %r %r" % (type(data),
                                 data))
diff --git a/libs/future/builtins/__init__.py b/libs/future/builtins/__init__.py
index 216465a15..8bc1649d2 100644
--- a/libs/future/builtins/__init__.py
+++ b/libs/future/builtins/__init__.py
@@ -11,7 +11,7 @@ from future.builtins.iterators import (filter, map, zip)
 # The isinstance import is no longer needed. We provide it only for
 # backward-compatibility with future v0.8.2. It will be removed in future v1.0.
 from future.builtins.misc import (ascii, chr, hex, input, isinstance, next,
-                                  oct, open, pow, round, super)
+                                  oct, open, pow, round, super, max, min)
 from future.utils import PY3
 
 if PY3:
@@ -43,7 +43,7 @@ if not utils.PY3:
     __all__ = ['filter', 'map', 'zip',
                'ascii', 'chr', 'hex', 'input', 'next', 'oct', 'open', 'pow',
                'round', 'super',
-               'bytes', 'dict', 'int', 'list', 'object', 'range', 'str',
+               'bytes', 'dict', 'int', 'list', 'object', 'range', 'str', 'max', 'min'
               ]
 
 else:
diff --git a/libs/future/builtins/misc.py b/libs/future/builtins/misc.py
index 90dc384ad..f86ce5f34 100644
--- a/libs/future/builtins/misc.py
+++ b/libs/future/builtins/misc.py
@@ -13,6 +13,8 @@ The builtin functions are:
 - ``open`` (equivalent to io.open on Py2)
 - ``super`` (backport of Py3's magic zero-argument super() function
 - ``round`` (new "Banker's Rounding" behaviour from Py3)
+- ``max`` (new default option from Py3.4)
+- ``min`` (new default option from Py3.4)
 
 ``isinstance`` is also currently exported for backwards compatibility
 with v0.8.2, although this has been deprecated since v0.9.
@@ -59,6 +61,8 @@ if utils.PY2:
     from future.builtins.newnext import newnext as next
     from future.builtins.newround import newround as round
     from future.builtins.newsuper import newsuper as super
+    from future.builtins.new_min_max import newmax as max
+    from future.builtins.new_min_max import newmin as min
     from future.types.newint import newint
 
     _SENTINEL = object()
@@ -89,11 +93,12 @@ if utils.PY2:
             else:
                 return _builtin_pow(x+0j, y, z)
 
+
     # ``future`` doesn't support Py3.0/3.1. If we ever did, we'd add this:
     #     callable = __builtin__.callable
 
     __all__ = ['ascii', 'chr', 'hex', 'input', 'isinstance', 'next', 'oct',
-               'open', 'pow', 'round', 'super']
+               'open', 'pow', 'round', 'super', 'max', 'min']
 
 else:
     import builtins
@@ -109,8 +114,14 @@ else:
     pow = builtins.pow
     round = builtins.round
     super = builtins.super
-
-    __all__ = []
+    if utils.PY34_PLUS:
+        max = builtins.max
+        min = builtins.min
+        __all__ = []
+    else:
+        from future.builtins.new_min_max import newmax as max
+        from future.builtins.new_min_max import newmin as min
+        __all__ = ['min', 'max']
 
     # The callable() function was removed from Py3.0 and 3.1 and
     # reintroduced into Py3.2+. ``future`` doesn't support Py3.0/3.1. If we ever
diff --git a/libs/future/builtins/new_min_max.py b/libs/future/builtins/new_min_max.py
new file mode 100644
index 000000000..6f0c2a86f
--- /dev/null
+++ b/libs/future/builtins/new_min_max.py
@@ -0,0 +1,59 @@
+import itertools
+
+from future import utils
+if utils.PY2:
+    from __builtin__ import max as _builtin_max, min as _builtin_min
+else:
+    from builtins import max as _builtin_max, min as _builtin_min
+
+_SENTINEL = object()
+
+
+def newmin(*args, **kwargs):
+    return new_min_max(_builtin_min, *args, **kwargs)
+
+
+def newmax(*args, **kwargs):
+    return new_min_max(_builtin_max, *args, **kwargs)
+
+
+def new_min_max(_builtin_func, *args, **kwargs):
+    """
+    To support the argument "default" introduced in python 3.4 for min and max
+    :param _builtin_func: builtin min or builtin max
+    :param args:
+    :param kwargs:
+    :return: returns the min or max based on the arguments passed
+    """
+
+    for key, _ in kwargs.items():
+        if key not in set(['key', 'default']):
+            raise TypeError('Illegal argument %s', key)
+
+    if len(args) == 0:
+        raise TypeError
+
+    if len(args) != 1 and kwargs.get('default', _SENTINEL) is not _SENTINEL:
+        raise TypeError
+
+    if len(args) == 1:
+        iterator = iter(args[0])
+        try:
+            first = next(iterator)
+        except StopIteration:
+            if kwargs.get('default', _SENTINEL) is not _SENTINEL:
+                return kwargs.get('default')
+            else:
+                raise ValueError('{}() arg is an empty sequence'.format(_builtin_func.__name__))
+        else:
+            iterator = itertools.chain([first], iterator)
+        if kwargs.get('key') is not None:
+            return _builtin_func(iterator, key=kwargs.get('key'))
+        else:
+            return _builtin_func(iterator)
+
+    if len(args) > 1:
+        if kwargs.get('key') is not None:
+            return _builtin_func(args, key=kwargs.get('key'))
+        else:
+            return _builtin_func(args)
diff --git a/libs/future/builtins/newround.py b/libs/future/builtins/newround.py
index 3943ebb6e..394a2c63c 100644
--- a/libs/future/builtins/newround.py
+++ b/libs/future/builtins/newround.py
@@ -38,11 +38,14 @@ def newround(number, ndigits=None):
         if 'numpy' in repr(type(number)):
             number = float(number)
 
-    if not PY26:
-        d = Decimal.from_float(number).quantize(exponent,
-                                            rounding=ROUND_HALF_EVEN)
+    if isinstance(number, Decimal):
+        d = number
     else:
-        d = from_float_26(number).quantize(exponent, rounding=ROUND_HALF_EVEN)
+        if not PY26:
+            d = Decimal.from_float(number).quantize(exponent,
+                                                rounding=ROUND_HALF_EVEN)
+        else:
+            d = from_float_26(number).quantize(exponent, rounding=ROUND_HALF_EVEN)
 
     if return_int:
         return int(d)
diff --git a/libs/future/moves/__init__.py b/libs/future/moves/__init__.py
index 040fdcf01..0cd60d3d5 100644
--- a/libs/future/moves/__init__.py
+++ b/libs/future/moves/__init__.py
@@ -4,5 +4,5 @@ import sys
 __future_module__ = True
 from future.standard_library import import_top_level_modules
 
-if sys.version_info[0] == 3:
+if sys.version_info[0] >= 3:
     import_top_level_modules()
diff --git a/libs/future/moves/copyreg.py b/libs/future/moves/copyreg.py
index 21c7a42f2..9d08cdc5e 100644
--- a/libs/future/moves/copyreg.py
+++ b/libs/future/moves/copyreg.py
@@ -2,7 +2,11 @@ from __future__ import absolute_import
 from future.utils import PY3
 
 if PY3:
-    from copyreg import *
+    import copyreg, sys
+    # A "*" import uses Python 3's copyreg.__all__ which does not include
+    # all public names in the API surface for copyreg, this avoids that
+    # problem by just making our module _be_ a reference to the actual module.
+    sys.modules['future.moves.copyreg'] = copyreg
 else:
     __future_module__ = True
     from copy_reg import *
diff --git a/libs/future/moves/urllib/request.py b/libs/future/moves/urllib/request.py
index 60e440a77..972aa4ab5 100644
--- a/libs/future/moves/urllib/request.py
+++ b/libs/future/moves/urllib/request.py
@@ -11,19 +11,8 @@ if PY3:
                                 proxy_bypass,
                                 quote,
                                 request_host,
-                                splitattr,
-                                splithost,
-                                splitpasswd,
-                                splitport,
-                                splitquery,
-                                splittag,
-                                splittype,
-                                splituser,
-                                splitvalue,
                                 thishost,
-                                to_bytes,
                                 unquote,
-                                unwrap,
                                 url2pathname,
                                 urlcleanup,
                                 urljoin,
@@ -32,6 +21,18 @@ if PY3:
                                 urlretrieve,
                                 urlsplit,
                                 urlunparse)
+
+    from urllib.parse import (splitattr,
+                              splithost,
+                              splitpasswd,
+                              splitport,
+                              splitquery,
+                              splittag,
+                              splittype,
+                              splituser,
+                              splitvalue,
+                              to_bytes,
+                              unwrap)
 else:
     __future_module__ = True
     with suspend_hooks():
diff --git a/libs/future/tests/base.py b/libs/future/tests/base.py
index 9f4607b69..4ef437baa 100644
--- a/libs/future/tests/base.py
+++ b/libs/future/tests/base.py
@@ -272,7 +272,11 @@ class CodeHandler(unittest.TestCase):
         else:
             headers = ''
 
-        self.compare(output, headers + reformat_code(expected),
+        reformatted = reformat_code(expected)
+        if headers in reformatted:
+            headers = ''
+
+        self.compare(output, headers + reformatted,
                      ignore_imports=ignore_imports)
 
     def unchanged(self, code, **kwargs):
@@ -338,6 +342,10 @@ class CodeHandler(unittest.TestCase):
                         '----\n%s\n----' % f.read(),
                     )
             ErrorClass = (FuturizeError if 'futurize' in script else PasteurizeError)
+
+            if not hasattr(e, 'output'):
+                # The attribute CalledProcessError.output doesn't exist on Py2.6
+                e.output = None
             raise ErrorClass(msg, e.returncode, e.cmd, output=e.output)
         return output
 
diff --git a/libs/future/types/newbytes.py b/libs/future/types/newbytes.py
index 2a337c864..c9d584a7c 100644
--- a/libs/future/types/newbytes.py
+++ b/libs/future/types/newbytes.py
@@ -5,15 +5,19 @@ Why do this? Without it, the Python 2 bytes object is a very, very
 different beast to the Python 3 bytes object.
 """
 
-from collections import Iterable
 from numbers import Integral
 import string
 import copy
 
-from future.utils import istext, isbytes, PY3, with_metaclass
+from future.utils import istext, isbytes, PY2, PY3, with_metaclass
 from future.types import no, issubset
 from future.types.newobject import newobject
 
+if PY2:
+    from collections import Iterable
+else:
+    from collections.abc import Iterable
+
 
 _builtin_bytes = bytes
 
diff --git a/libs/future/types/newint.py b/libs/future/types/newint.py
index 705b8fa95..748dba9d2 100644
--- a/libs/future/types/newint.py
+++ b/libs/future/types/newint.py
@@ -8,7 +8,6 @@ They are very similar. The most notable difference is:
 from __future__ import division
 
 import struct
-import collections
 
 from future.types.newbytes import newbytes
 from future.types.newobject import newobject
@@ -17,6 +16,9 @@ from future.utils import PY3, isint, istext, isbytes, with_metaclass, native
 
 if PY3:
     long = int
+    from collections.abc import Iterable
+else:
+    from collections import Iterable
 
 
 class BaseNewInt(type):
@@ -356,7 +358,7 @@ class newint(with_metaclass(BaseNewInt, long)):
             raise TypeError("cannot convert unicode objects to bytes")
         # mybytes can also be passed as a sequence of integers on Py3.
         # Test for this:
-        elif isinstance(mybytes, collections.Iterable):
+        elif isinstance(mybytes, Iterable):
             mybytes = newbytes(mybytes)
         b = mybytes if byteorder == 'big' else mybytes[::-1]
         if len(b) == 0:
diff --git a/libs/future/types/newmemoryview.py b/libs/future/types/newmemoryview.py
index 72c6990a7..09f804dcf 100644
--- a/libs/future/types/newmemoryview.py
+++ b/libs/future/types/newmemoryview.py
@@ -1,14 +1,16 @@
 """
 A pretty lame implementation of a memoryview object for Python 2.6.
 """
-
-from collections import Iterable
 from numbers import Integral
 import string
 
-from future.utils import istext, isbytes, PY3, with_metaclass
+from future.utils import istext, isbytes, PY2, with_metaclass
 from future.types import no, issubset
 
+if PY2:
+    from collections import Iterable
+else:
+    from collections.abc import Iterable
 
 # class BaseNewBytes(type):
 #     def __instancecheck__(cls, instance):
diff --git a/libs/future/types/newobject.py b/libs/future/types/newobject.py
index 776d47664..31b84fc12 100644
--- a/libs/future/types/newobject.py
+++ b/libs/future/types/newobject.py
@@ -112,5 +112,6 @@ class newobject(object):
         """
         return object(self)
 
+    __slots__ = []
 
 __all__ = ['newobject']
diff --git a/libs/future/types/newrange.py b/libs/future/types/newrange.py
index 9173b0509..eda01a5a5 100644
--- a/libs/future/types/newrange.py
+++ b/libs/future/types/newrange.py
@@ -19,7 +19,12 @@ From Dan Crosta's README:
 """
 from __future__ import absolute_import
 
-from collections import Sequence, Iterator
+from future.utils import PY2
+
+if PY2:
+    from collections import Sequence, Iterator
+else:
+    from collections.abc import Sequence, Iterator
 from itertools import islice
 
 from future.backports.misc import count   # with step parameter on Py2.6
diff --git a/libs/future/types/newstr.py b/libs/future/types/newstr.py
index e6272fb90..8ca191f97 100644
--- a/libs/future/types/newstr.py
+++ b/libs/future/types/newstr.py
@@ -40,7 +40,6 @@ representations of your objects portably across Py3 and Py2, use the
 
 """
 
-from collections import Iterable
 from numbers import Number
 
 from future.utils import PY3, istext, with_metaclass, isnewbytes
@@ -51,6 +50,9 @@ from future.types.newobject import newobject
 if PY3:
     # We'll probably never use newstr on Py3 anyway...
     unicode = str
+    from collections.abc import Iterable
+else:
+    from collections import Iterable
 
 
 class BaseNewStr(type):
@@ -105,6 +107,7 @@ class newstr(with_metaclass(BaseNewStr, unicode)):
         """
         Without the u prefix
         """
+
         value = super(newstr, self).__repr__()
         # assert value[0] == u'u'
         return value[1:]
@@ -290,7 +293,14 @@ class newstr(with_metaclass(BaseNewStr, unicode)):
             isinstance(other, bytes) and not isnewbytes(other)):
             return super(newstr, self).__eq__(other)
         else:
-            return False
+            return NotImplemented
+
+    def __hash__(self):
+        if (isinstance(self, unicode) or
+            isinstance(self, bytes) and not isnewbytes(self)):
+            return super(newstr, self).__hash__()
+        else:
+            raise NotImplementedError()
 
     def __ne__(self, other):
         if (isinstance(other, unicode) or
diff --git a/libs/future/utils/__init__.py b/libs/future/utils/__init__.py
index 906f1e464..46bd96def 100644
--- a/libs/future/utils/__init__.py
+++ b/libs/future/utils/__init__.py
@@ -18,8 +18,10 @@ This module exports useful functions for 2/3 compatible code:
     * types:
 
         * text_type: unicode in Python 2, str in Python 3
-        * binary_type: str in Python 2, bytes in Python 3
         * string_types: basestring in Python 2, str in Python 3
+        * binary_type: str in Python 2, bytes in Python 3
+        * integer_types: (int, long) in Python 2, int in Python 3
+        * class_types: (type, types.ClassType) in Python 2, type in Python 3
 
     * bchr(c):
         Take an integer and make a 1-character byte string
@@ -55,7 +57,8 @@ import copy
 import inspect
 
 
-PY3 = sys.version_info[0] == 3
+PY3 = sys.version_info[0] >= 3
+PY34_PLUS = sys.version_info[0:2] >= (3, 4)
 PY35_PLUS = sys.version_info[0:2] >= (3, 5)
 PY36_PLUS = sys.version_info[0:2] >= (3, 6)
 PY2 = sys.version_info[0] == 2
@@ -405,12 +408,34 @@ if PY3:
         allows re-raising exceptions with the cls value and traceback on
         Python 2 and 3.
         """
-        if value is not None and isinstance(tp, Exception):
-            raise TypeError("instance exception may not have a separate value")
-        if value is not None:
-            exc = tp(value)
-        else:
+        if isinstance(tp, BaseException):
+            # If the first object is an instance, the type of the exception
+            # is the class of the instance, the instance itself is the value,
+            # and the second object must be None.
+            if value is not None:
+                raise TypeError("instance exception may not have a separate value")
             exc = tp
+        elif isinstance(tp, type) and not issubclass(tp, BaseException):
+            # If the first object is a class, it becomes the type of the
+            # exception.
+            raise TypeError("class must derive from BaseException, not %s" % tp.__name__)
+        else:
+            # The second object is used to determine the exception value: If it
+            # is an instance of the class, the instance becomes the exception
+            # value. If the second object is a tuple, it is used as the argument
+            # list for the class constructor; if it is None, an empty argument
+            # list is used, and any other object is treated as a single argument
+            # to the constructor. The instance so created by calling the
+            # constructor is used as the exception value.
+            if isinstance(value, tp):
+                exc = value
+            elif isinstance(value, tuple):
+                exc = tp(*value)
+            elif value is None:
+                exc = tp()
+            else:
+                exc = tp(value)
+
         if exc.__traceback__ is not tb:
             raise exc.with_traceback(tb)
         raise exc
@@ -443,12 +468,14 @@ else:
         e.__suppress_context__ = False
         if isinstance(cause, type) and issubclass(cause, Exception):
             e.__cause__ = cause()
+            e.__cause__.__traceback__ = sys.exc_info()[2]
             e.__suppress_context__ = True
         elif cause is None:
             e.__cause__ = None
             e.__suppress_context__ = True
         elif isinstance(cause, BaseException):
             e.__cause__ = cause
+            object.__setattr__(e.__cause__,  '__traceback__', sys.exc_info()[2])
             e.__suppress_context__ = True
         else:
             raise TypeError("exception causes must derive from BaseException")
@@ -552,15 +579,14 @@ def isbytes(obj):
 
 def isnewbytes(obj):
     """
-    Equivalent to the result of ``isinstance(obj, newbytes)`` were
-    ``__instancecheck__`` not overridden on the newbytes subclass. In
-    other words, it is REALLY a newbytes instance, not a Py2 native str
+    Equivalent to the result of ``type(obj)  == type(newbytes)``
+    in other words, it is REALLY a newbytes instance, not a Py2 native str
     object?
+
+    Note that this does not cover subclasses of newbytes, and it is not
+    equivalent to ininstance(obj, newbytes)
     """
-    # TODO: generalize this so that it works with subclasses of newbytes
-    # Import is here to avoid circular imports:
-    from future.types.newbytes import newbytes
-    return type(obj) == newbytes
+    return type(obj).__name__ == 'newbytes'
 
 
 def isint(obj):
@@ -726,16 +752,16 @@ else:
 
 
 __all__ = ['PY2', 'PY26', 'PY3', 'PYPY',
-           'as_native_str', 'bind_method', 'bord', 'bstr',
-           'bytes_to_native_str', 'encode_filename', 'ensure_new_type',
-           'exec_', 'get_next', 'getexception', 'implements_iterator',
-           'is_new_style', 'isbytes', 'isidentifier', 'isint',
-           'isnewbytes', 'istext', 'iteritems', 'iterkeys', 'itervalues',
-           'lfilter', 'listitems', 'listvalues', 'lmap', 'lrange',
-           'lzip', 'native', 'native_bytes', 'native_str',
+           'as_native_str', 'binary_type', 'bind_method', 'bord', 'bstr',
+           'bytes_to_native_str', 'class_types', 'encode_filename',
+           'ensure_new_type', 'exec_', 'get_next', 'getexception',
+           'implements_iterator', 'integer_types', 'is_new_style', 'isbytes',
+           'isidentifier', 'isint', 'isnewbytes', 'istext', 'iteritems',
+           'iterkeys', 'itervalues', 'lfilter', 'listitems', 'listvalues',
+           'lmap', 'lrange', 'lzip', 'native', 'native_bytes', 'native_str',
            'native_str_to_bytes', 'old_div',
            'python_2_unicode_compatible', 'raise_',
-           'raise_with_traceback', 'reraise', 'text_to_native_str',
-           'tobytes', 'viewitems', 'viewkeys', 'viewvalues',
-           'with_metaclass'
-          ]
+           'raise_with_traceback', 'reraise', 'string_types',
+           'text_to_native_str', 'text_type', 'tobytes', 'viewitems',
+           'viewkeys', 'viewvalues', 'with_metaclass'
+           ]