Drop Python 2

.github/PULL_REQUEST_TEMPLATE.md

@@ -3,7 +3,6 @@
 TODO:
 * [ ] Unit tests and/or doctests in docstrings
 * [ ] ``tox -e py38`` passes locally
-* [ ] ``tox -e py27`` passes locally
 * [ ] Docstrings and API docs for any new/modified user-facing classes and functions
 * [ ] Changes documented in docs/release.rst
 * [ ] ``tox -e docs`` passes locally

.travis.yml

@@ -12,9 +12,6 @@ addons:
 
 matrix:
   include:
-    - os: linux
-      language: python
-      python: 2.7
     - os: linux
       language: python
       python: 3.5

appveyor.yml

@@ -12,10 +12,6 @@ environment:
 
   matrix:
 
-    - PYTHON: "C:\\Python27-x64"
-      PYTHON_VERSION: "2.7"
-      DISTUTILS_USE_SDK: "1"
-
     - PYTHON: "C:\\Python35-x64"
       PYTHON_VERSION: "3.5"
 

docs/conf.py

@@ -16,16 +16,7 @@
 
 import sys
 import os
-
-
-PY2 = sys.version_info[0] == 2
-
-
-if PY2:  # pragma: py3 no cover
-    from mock import Mock as MagicMock
-else:    # pragma: py2 no cover
-    from unittest.mock import Mock as MagicMock
-
+from unittest.mock import Mock as MagicMock
 
 class Mock(MagicMock):
     @classmethod
@@ -34,10 +25,6 @@ def __getattr__(cls, name):
 
 
 MOCK_MODULES = ['msgpack']
-if PY2:
-    MOCK_MODULES.append('lzma')
-
-
 sys.modules.update((mod_name, Mock()) for mod_name in MOCK_MODULES)
 
 

docs/contributing.rst

@@ -145,9 +145,9 @@ To also run the doctests within docstrings, run::
 Tests can be run under different Python versions using tox. E.g. (assuming you have the
 corresponding Python interpreters installed on your system)::
 
-    $ tox -e py27,py35,py36,py37,py38
+    $ tox -e py35,py36,py37,py38
 
-NumCodecs currently supports Python 2.7 and Python 3.5-3.8, so the above command must
+NumCodecs currently supports Python 3.5-3.8, so the above command must
 succeed before code can be accepted into the main code base. Note that only the py38
 tox environment runs the doctests, i.e., doctests only need to succeed under Python 3.8.
 

docs/release.rst

@@ -1,6 +1,12 @@
 Release notes
 =============
 
+Upcoming Release
+----------------
+
+* Drop support for Python 2.
+  By :user:`James Bourbeau <jrbourbeau>`, :issue:`220`.
+
 
 .. _release_0.6.4:
 

numcodecs/__init__.py

@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # flake8: noqa
 """Numcodecs is a Python package providing buffer compression and
 transformation codecs for use in data storage and communication
@@ -18,7 +17,6 @@
 
 """
 
-from __future__ import absolute_import, print_function, division
 import multiprocessing
 import atexit
 

numcodecs/abc.py

@@ -1,11 +1,9 @@
-# -*- coding: utf-8 -*-
 """This module defines the :class:`Codec` base class, a common interface for
 all codec classes.
 
 Codec classes must implement :func:`Codec.encode` and :func:`Codec.decode`
 methods. Inputs to and outputs from these methods may be any Python object
-exporting a contiguous buffer via the new-style Python protocol
-or :class:`array.array` under Python 2.
+exporting a contiguous buffer via the new-style Python protocol.
 
 Codec classes must implement a :func:`Codec.get_config` method,
 which must return a dictionary holding all configuration parameters
@@ -29,10 +27,9 @@
 other and vice versa.
 
 """
-from __future__ import absolute_import, print_function, division
 
 
-class Codec(object):
+class Codec:
     """Codec abstract base class."""
 
     # override in sub-class
@@ -46,13 +43,13 @@ def encode(self, buf):  # pragma: no cover
         ----------
         buf : buffer-like
             Data to be encoded. May be any object supporting the new-style
-            buffer protocol or `array.array` under Python 2.
+            buffer protocol.
 
         Returns
         -------
         enc : buffer-like
             Encoded data. May be any object supporting the new-style buffer
-            protocol or `array.array` under Python 2.
+            protocol.
 
         """
         # override in sub-class
@@ -65,7 +62,7 @@ def decode(self, buf, out=None):  # pragma: no cover
         ----------
         buf : buffer-like
             Encoded data. May be any object supporting the new-style buffer
-            protocol or `array.array` under Python 2.
+            protocol.
         out : buffer-like, optional
             Writeable buffer to store decoded data. N.B. if provided, this buffer must
             be exactly the right size to store the decoded data.
@@ -74,7 +71,7 @@ def decode(self, buf, out=None):  # pragma: no cover
         -------
         dec : buffer-like
             Decoded data. May be any object supporting the new-style
-            buffer protocol or `array.array` under Python 2.
+            buffer protocol.
 
         """
         # override in sub-class
@@ -117,10 +114,6 @@ def __eq__(self, other):
         except AttributeError:
             return False
 
-    def __ne__(self, other):
-        # only needed for PY2
-        return not self == other
-
     def __repr__(self):
 
         # override in sub-class if need special representation
@@ -129,7 +122,7 @@ def __repr__(self):
         # parameters and valid keyword arguments to constructor function
 
         r = '%s(' % type(self).__name__
-        params = ['%s=%r' % (k, getattr(self, k))
+        params = ['{}={!r}'.format(k, getattr(self, k))
                   for k in sorted(self.__dict__)
                   if not k.startswith('_')]
         r += ', '.join(params) + ')'

numcodecs/astype.py

@@ -1,6 +1,3 @@
-# -*- coding: utf-8 -*-
-from __future__ import absolute_import, print_function, division
-
 import numpy as np
 
 from .abc import Codec
@@ -79,7 +76,7 @@ def get_config(self):
 
     def __repr__(self):
         return (
-            '%s(encode_dtype=%r, decode_dtype=%r)' % (
+            '{}(encode_dtype={!r}, decode_dtype={!r})'.format(
                 type(self).__name__,
                 self.encode_dtype.str,
                 self.decode_dtype.str