Remove mentions / workaround for unsupported Python versions

There are some stale mentions in docs / comments about
Python versions that are no longer supported. There
are also some workarounds to make driver work with those
versions. This commit removes all mentions and workarounds
that I was able to find.

Author: Lorak-mmk

CONTRIBUTING.rst

@@ -26,7 +26,6 @@ To protect the community, all contributors are required to `sign the DataStax Co
 
 Design and Implementation Guidelines
 ------------------------------------
-- We support Python 2.7+, so any changes must work in any of these runtimes (we use ``six``, ``futures``, and some internal backports for compatability)
 - We have integrations (notably Cassandra cqlsh) that require pure Python and minimal external dependencies. We try to avoid new external dependencies. Where compiled extensions are concerned, there should always be a pure Python fallback implementation.
 - This project follows `semantic versioning <http://semver.org/>`_, so breaking API changes will only be introduced in major versions.
 - Legacy ``cqlengine`` has varying degrees of overreaching client-side validation. Going forward, we will avoid client validation where server feedback is adequate and not overly expensive.

cassandra/encoder.py

@@ -34,9 +34,6 @@
 
 
 def cql_quote(term):
-    # The ordering of this method is important for the result of this method to
-    # be a native str type (for both Python 2 and 3)
-
     if isinstance(term, str):
         return "'%s'" % str(term).replace("'", "''")
     else:

cassandra/util.py

@@ -13,17 +13,22 @@
 # limitations under the License.
 
 from __future__ import with_statement
+from _weakref import ref
 import calendar
+from collections import OrderedDict
 from collections.abc import Mapping
 import datetime
 from functools import total_ordering
-import logging
 from itertools import chain
+import keyword
+import logging
 import pickle
 import random
 import re
-import uuid
+import socket
 import sys
+import time
+import uuid
 
 _HAS_GEOMET = True
 try:
@@ -213,147 +218,6 @@ def _resolve_contact_points_to_string_map(contact_points):
     )
 
 
-try:
-    from collections import OrderedDict
-except ImportError:
-    # OrderedDict from Python 2.7+
-
-    # Copyright (c) 2009 Raymond Hettinger
-    #
-    # Permission is hereby granted, free of charge, to any person
-    # obtaining a copy of this software and associated documentation files
-    # (the "Software"), to deal in the Software without restriction,
-    # including without limitation the rights to use, copy, modify, merge,
-    # publish, distribute, sublicense, and/or sell copies of the Software,
-    # and to permit persons to whom the Software is furnished to do so,
-    # subject to the following conditions:
-    #
-    #     The above copyright notice and this permission notice shall be
-    #     included in all copies or substantial portions of the Software.
-    #
-    #     THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
-    #     EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
-    #     OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
-    #     NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
-    #     HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
-    #     WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
-    #     FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
-    #     OTHER DEALINGS IN THE SOFTWARE.
-    from UserDict import DictMixin
-
-    class OrderedDict(dict, DictMixin):  # noqa
-        """ A dictionary which maintains the insertion order of keys. """
-
-        def __init__(self, *args, **kwds):
-            """ A dictionary which maintains the insertion order of keys. """
-
-            if len(args) > 1:
-                raise TypeError('expected at most 1 arguments, got %d' % len(args))
-            try:
-                self.__end
-            except AttributeError:
-                self.clear()
-            self.update(*args, **kwds)
-
-        def clear(self):
-            self.__end = end = []
-            end += [None, end, end]         # sentinel node for doubly linked list
-            self.__map = {}                 # key --> [key, prev, next]
-            dict.clear(self)
-
-        def __setitem__(self, key, value):
-            if key not in self:
-                end = self.__end
-                curr = end[1]
-                curr[2] = end[1] = self.__map[key] = [key, curr, end]
-            dict.__setitem__(self, key, value)
-
-        def __delitem__(self, key):
-            dict.__delitem__(self, key)
-            key, prev, next = self.__map.pop(key)
-            prev[2] = next
-            next[1] = prev
-
-        def __iter__(self):
-            end = self.__end
-            curr = end[2]
-            while curr is not end:
-                yield curr[0]
-                curr = curr[2]
-
-        def __reversed__(self):
-            end = self.__end
-            curr = end[1]
-            while curr is not end:
-                yield curr[0]
-                curr = curr[1]
-
-        def popitem(self, last=True):
-            if not self:
-                raise KeyError('dictionary is empty')
-            if last:
-                key = next(reversed(self))
-            else:
-                key = next(iter(self))
-            value = self.pop(key)
-            return key, value
-
-        def __reduce__(self):
-            items = [[k, self[k]] for k in self]
-            tmp = self.__map, self.__end
-            del self.__map, self.__end
-            inst_dict = vars(self).copy()
-            self.__map, self.__end = tmp
-            if inst_dict:
-                return (self.__class__, (items,), inst_dict)
-            return self.__class__, (items,)
-
-        def keys(self):
-            return list(self)
-
-        setdefault = DictMixin.setdefault
-        update = DictMixin.update
-        pop = DictMixin.pop
-        values = DictMixin.values
-        items = DictMixin.items
-        iterkeys = DictMixin.iterkeys
-        itervalues = DictMixin.itervalues
-        iteritems = DictMixin.iteritems
-
-        def __repr__(self):
-            if not self:
-                return '%s()' % (self.__class__.__name__,)
-            return '%s(%r)' % (self.__class__.__name__, self.items())
-
-        def copy(self):
-            return self.__class__(self)
-
-        @classmethod
-        def fromkeys(cls, iterable, value=None):
-            d = cls()
-            for key in iterable:
-                d[key] = value
-            return d
-
-        def __eq__(self, other):
-            if isinstance(other, OrderedDict):
-                if len(self) != len(other):
-                    return False
-                for p, q in zip(self.items(), other.items()):
-                    if p != q:
-                        return False
-                return True
-            return dict.__eq__(self, other)
-
-        def __ne__(self, other):
-            return not self == other
-
-
-# WeakSet from Python 2.7+ (https://code.google.com/p/weakrefset)
-
-from _weakref import ref
-
-
 class _IterationGuard(object):
     # This context manager registers itself in the current iterators of the
     # weak container, such as to delay all removals until the context manager
@@ -916,10 +780,6 @@ def _serialize_key(self, key):
         return self.cass_key_type.serialize(key, self.protocol_version)
 
 
-import datetime
-import time
-
-
 @total_ordering
 class Time(object):
     '''
@@ -1145,97 +1005,9 @@ def __str__(self):
             # If we overflow datetime.[MIN|MAX]
             return str(self.days_from_epoch)
 
-import socket
-if hasattr(socket, 'inet_pton'):
-    inet_pton = socket.inet_pton
-    inet_ntop = socket.inet_ntop
-else:
-    """
-    Windows doesn't have socket.inet_pton and socket.inet_ntop until Python 3.4
-    This is an alternative impl using ctypes, based on this win_inet_pton project:
-    https://github.com/hickeroar/win_inet_pton
-    """
-    import ctypes
-
-    class sockaddr(ctypes.Structure):
-        """
-        Shared struct for ipv4 and ipv6.
-
-        https://msdn.microsoft.com/en-us/library/windows/desktop/ms740496(v=vs.85).aspx
-
-        ``__pad1`` always covers the port.
 
-        When being used for ``sockaddr_in6``, ``ipv4_addr`` actually covers ``sin6_flowinfo``, resulting
-        in proper alignment for ``ipv6_addr``.
-        """
-        _fields_ = [("sa_family", ctypes.c_short),
-                    ("__pad1", ctypes.c_ushort),
-                    ("ipv4_addr", ctypes.c_byte * 4),
-                    ("ipv6_addr", ctypes.c_byte * 16),
-                    ("__pad2", ctypes.c_ulong)]
-
-    if hasattr(ctypes, 'windll'):
-        WSAStringToAddressA = ctypes.windll.ws2_32.WSAStringToAddressA
-        WSAAddressToStringA = ctypes.windll.ws2_32.WSAAddressToStringA
-    else:
-        def not_windows(*args):
-            raise OSError("IPv6 addresses cannot be handled on Windows. "
-                            "Missing ctypes.windll")
-        WSAStringToAddressA = not_windows
-        WSAAddressToStringA = not_windows
-
-    def inet_pton(address_family, ip_string):
-        if address_family == socket.AF_INET:
-            return socket.inet_aton(ip_string)
-
-        addr = sockaddr()
-        addr.sa_family = address_family
-        addr_size = ctypes.c_int(ctypes.sizeof(addr))
-
-        if WSAStringToAddressA(
-                ip_string,
-                address_family,
-                None,
-                ctypes.byref(addr),
-                ctypes.byref(addr_size)
-        ) != 0:
-            raise socket.error(ctypes.FormatError())
-
-        if address_family == socket.AF_INET6:
-            return ctypes.string_at(addr.ipv6_addr, 16)
-
-        raise socket.error('unknown address family')
-
-    def inet_ntop(address_family, packed_ip):
-        if address_family == socket.AF_INET:
-            return socket.inet_ntoa(packed_ip)
-
-        addr = sockaddr()
-        addr.sa_family = address_family
-        addr_size = ctypes.c_int(ctypes.sizeof(addr))
-        ip_string = ctypes.create_string_buffer(128)
-        ip_string_size = ctypes.c_int(ctypes.sizeof(ip_string))
-
-        if address_family == socket.AF_INET6:
-            if len(packed_ip) != ctypes.sizeof(addr.ipv6_addr):
-                raise socket.error('packed IP wrong length for inet_ntoa')
-            ctypes.memmove(addr.ipv6_addr, packed_ip, 16)
-        else:
-            raise socket.error('unknown address family')
-
-        if WSAAddressToStringA(
-                ctypes.byref(addr),
-                addr_size,
-                None,
-                ip_string,
-                ctypes.byref(ip_string_size)
-        ) != 0:
-            raise socket.error(ctypes.FormatError())
-
-        return ip_string[:ip_string_size.value - 1]
-
-
-import keyword
+inet_pton = socket.inet_pton
+inet_ntop = socket.inet_ntop
 
 
 # similar to collections.namedtuple, reproduced here because Python 2.6 did not have the rename logic

docs/installation.rst

@@ -3,7 +3,7 @@ Installation
 
 Supported Platforms
 -------------------
-Python 2.7, 3.5, 3.6, 3.7 and 3.8 are supported. Both CPython (the standard Python
+Python versions 3.6-3.11 are supported. Both CPython (the standard Python
 implementation) and `PyPy <http://pypy.org>`_ are supported and tested.
 
 Linux, OSX, and Windows are supported.

tests/integration/__init__.py

@@ -392,7 +392,6 @@ def _id_and_mark(f):
 incorrect_test = lambda reason='This test seems to be incorrect and should be fixed', *args, **kwargs: pytest.mark.xfail(reason=reason, *args, **kwargs)
 
 pypy = unittest.skipUnless(platform.python_implementation() == "PyPy", "Test is skipped unless it's on PyPy")
-notpy3 = unittest.skipIf(sys.version_info >= (3, 0), "Test not applicable for Python 3.x runtime")
 requiresmallclockgranularity = unittest.skipIf("Windows" in platform.system() or "asyncore" in EVENT_LOOP_MANAGER,
                                                "This test is not suitible for environments with large clock granularity")
 requiressimulacron = unittest.skipIf(SIMULACRON_JAR is None or CASSANDRA_VERSION < Version("2.1"), "Simulacron jar hasn't been specified or C* version is 2.0")