Drop support for python 2.7

.appveyor.yml

@@ -5,7 +5,6 @@ environment:
   CONDA_PATH: "C:\\Miniconda"
 
   matrix:
-    - PYTHON_VERSION: "2.7"
     - PYTHON_VERSION: "3.6"
     - PYTHON_VERSION: "3.7"
 

.travis.yml

@@ -23,7 +23,6 @@ git:
 python:
   - 3.7
   - 3.6
-  - 2.7
 
 cache:
   - pip
@@ -50,11 +49,6 @@ env:
 
 matrix:
   include:
-    - python: 2.7
-      env:
-        - VERSIONS="numpy==1.12.0 matplotlib==2.0.0 scipy==0.17.0 pint==0.8 xarray==0.10.7 pandas==0.22.0"
-        - TASK="coverage"
-        - TEST_OUTPUT_CONTROL=""
     - python: "3.7-dev"
       env: PRE="--pre"
     - python: "3.7-dev"

README.rst

@@ -80,9 +80,9 @@ release new features, and `y` when we make a release with only bug fixes.
 For additional MetPy examples not included in this repository, please see the `Unidata Python
 Gallery <https://unidata.github.io/python-gallery/>`_.
 
-We support Python >= 3.6 and currently support Python 2.7.
+We support Python >= 3.6.
 
-NOTE: We are dropping support for Python 2.7 in Fall 2019. See
+0.12 is the first version to drop support for Python 2.7 in Fall 2019. See
 `here <https://github.com/Unidata/MetPy/blob/master/docs/installguide.rst>`_ for more
 information.
 
@@ -115,9 +115,6 @@ Other required packages:
 - Pint
 - Xarray
 
-Python 2.7 requires the enum34 package, which is a backport
-of the standard library enum module.
-
 There is also an optional dependency on the pyproj library for geographic
 projections (used with cross sections, grid spacing calculation, and the GiniFile interface).
 

docs/index.rst

@@ -38,11 +38,7 @@ release new features, and `y` when we make a release with only bug fixes.
 For additional MetPy examples not included in this repository, please see the `Unidata Python
 Gallery <https://unidata.github.io/python-gallery/>`_.
 
-We support Python >= 3.6 and currently support Python 2.7.
-
-.. warning::
-  We are dropping support for Python 2.7 in the Fall of 2019. For more details and rationale
-  behind this decision, see :ref:`python27`.
+We support Python >= 3.6. Support for Python 2.7 was dropped with the release of 0.12.
 
 ----------
 Contact Us

docs/installguide.rst

@@ -2,47 +2,19 @@
 Installation Guide
 ==================
 
-.. _python27:
-
-------------------
-Python 2.7 Support
-------------------
-In the Fall 2019, we will be dropping support for Python 2.7. This follows movement from
-other packages within the `scientific Python ecosystem <https://python3statement.org/>`_.
-This includes:
-
-* Core Python developers will
-  `stop support for Python 2.7 January 1, 2020 <https://pythonclock.org/>`_
-* NumPy feature releases will be
-  `Python 3 only starting January 1, 2019 <https://www.numpy.org/neps/nep-0014-dropping-python2.7-proposal.html>`_,
-  and support for the last release supporting Python 2 will end January 1, 2020.
-* XArray will drop
-  `2.7 January 1, 2019 as well <https://github.com/pydata/xarray/issues/1830>`_
-* Matplotlib's 3.0 release, tentatively Summer 2018,
-  `will be Python 3 only <https://mail.python.org/pipermail/matplotlib-devel/2017-October/000892.html>`_;
-  the current 2.2 release will be the last long term release that supports 2.7, and its support
-  will cease January 1, 2020.
-
-The last release of MetPy before this time (Spring or Summer 2019) will be the last that
-support Python 2.7. This version of MetPy will **not** receive any long term support or
-additional bug fix releases after the next minor release. The packages for this version *will*
-remain available on Conda or PyPI.
-
 ------------
 Requirements
 ------------
 In general, MetPy tries to support minor versions of dependencies released within the last two
-years. For Python itself, that means supporting the last two minor releases, as well as
-currently supporting Python 2.7.
+years. For Python itself, that means supporting the last two minor releases.
 
-* matplotlib >= 2.0.0
-* numpy >= 1.12.0
-* scipy >= 0.17.0
+* matplotlib >= 2.1.0
+* numpy >= 1.13.0
+* scipy >= 1.0.0
 * pint >= 0.8
 * pandas >= 0.22.0
 * xarray >= 0.10.7
 * traitlets >= 4.3.0
-* enum34 (for python < 3.4)
 * pooch >= 0.1
 
 ------------

docs/roadmap.rst

@@ -158,5 +158,3 @@ Here are a few more items that did not fit above:
     it would not incur packaging challenges. Past experiments with Numba and MetPy have not
     been promising, though.
   - Make more calculations (e.g. CAPE) work on grids of data
-
-* Drop Python 2! For more info see :ref:`python27`.

metpy/__init__.py

@@ -16,9 +16,5 @@
 __version__ = get_versions()['version']
 del get_versions
 
-try:
-    # Added in Python 3.2, will log anything warning or higher to stderr
-    logging.lastResort
-except AttributeError:
-    # Add our own for MetPy on Python 2.7
-    logging.getLogger(__name__).addHandler(logging.StreamHandler())
+# Added in Python 3.2, will log anything warning or higher to stderr
+logging.lastResort

metpy/calc/basic.py

@@ -9,9 +9,6 @@
 * heat index
 * windchill
 """
-
-from __future__ import division
-
 import warnings
 
 import numpy as np

metpy/calc/kinematics.py

@@ -2,8 +2,6 @@
 # Distributed under the terms of the BSD 3-Clause License.
 # SPDX-License-Identifier: BSD-3-Clause
 """Contains calculation of kinematic parameters (e.g. divergence or vorticity)."""
-from __future__ import division
-
 import functools
 import warnings
 
@@ -12,7 +10,7 @@
 from . import coriolis_parameter
 from .tools import first_derivative, get_layer_heights, gradient
 from .. import constants as mpconsts
-from ..cbook import is_string_like, iterable
+from ..cbook import iterable
 from ..package_tools import Exporter
 from ..units import atleast_2d, check_units, concatenate, units
 from ..xarray import preprocess_xarray
@@ -38,7 +36,7 @@ def _check_and_flip(arr):
             return arr.T
         else:
             return arr
-    elif not is_string_like(arr) and iterable(arr):
+    elif not isinstance(arr, str) and iterable(arr):
         return tuple(_check_and_flip(a) for a in arr)
     else:
         return arr

metpy/calc/thermo.py

@@ -2,9 +2,6 @@
 # Distributed under the terms of the BSD 3-Clause License.
 # SPDX-License-Identifier: BSD-3-Clause
 """Contains a collection of thermodynamic calculations."""
-
-from __future__ import division
-
 import warnings
 
 import numpy as np

metpy/calc/tools.py

@@ -2,19 +2,12 @@
 # Distributed under the terms of the BSD 3-Clause License.
 # SPDX-License-Identifier: BSD-3-Clause
 """Contains a collection of generally useful calculation tools."""
-from __future__ import division
-
 import functools
 from operator import itemgetter
 import warnings
 
 import numpy as np
-try:
-    from numpy.core.numeric import normalize_axis_index
-except ImportError:  # Only available in numpy >=1.13.0
-    def normalize_axis_index(a, n):
-        """No op version of :func:`numpy.core.numeric.normalize_axis_index`."""
-        return a
+from numpy.core.numeric import normalize_axis_index
 import numpy.ma as ma
 from scipy.spatial import cKDTree
 import xarray as xr

metpy/cbook.py

@@ -16,12 +16,6 @@
     string_type = str
 
 
-# TODO: This can go away when we remove Python 2
-def is_string_like(s):
-    """Check if an object is a string."""
-    return isinstance(s, string_type)
-
-
 POOCH = pooch.create(
     path=pooch.os_cache('metpy'),
     base_url='https://github.com/Unidata/MetPy/raw/{version}/staticdata/',
@@ -109,4 +103,4 @@ def iterable(value):
     return np.iterable(value)
 
 
-__all__ = ('Registry', 'broadcast_indices', 'get_test_data', 'is_string_like', 'iterable')
+__all__ = ('Registry', 'broadcast_indices', 'get_test_data', 'iterable')

metpy/interpolate/geometry.py

@@ -3,8 +3,6 @@
 # SPDX-License-Identifier: BSD-3-Clause
 """Tools for working with geometric objects (points, triangles, polygons)."""
 
-from __future__ import division
-
 import logging
 import math
 

metpy/interpolate/grid.py

@@ -3,8 +3,6 @@
 # SPDX-License-Identifier: BSD-3-Clause
 """Tools and calculations for interpolating specifically to a grid."""
 
-from __future__ import division
-
 import numpy as np
 
 # Change when Python 2.7 no longer supported

metpy/interpolate/one_dimension.py

@@ -2,8 +2,6 @@
 # Distributed under the terms of the BSD 3-Clause License.
 # SPDX-License-Identifier: BSD-3-Clause
 """Interpolate data along a single axis."""
-from __future__ import absolute_import, division
-
 import warnings
 
 import numpy as np

metpy/interpolate/points.py

@@ -3,8 +3,6 @@
 # SPDX-License-Identifier: BSD-3-Clause
 """Interpolate data valid at one set of points to another in multiple dimensions."""
 
-from __future__ import division
-
 import logging
 
 import numpy as np

metpy/interpolate/tools.py

@@ -3,8 +3,6 @@
 # SPDX-License-Identifier: BSD-3-Clause
 """Assorted tools in support of interpolation functionality."""
 
-from __future__ import division
-
 import numpy as np
 
 from ..package_tools import Exporter

metpy/io/_nexrad_msgs/parse_spec.py

@@ -4,8 +4,6 @@
 # SPDX-License-Identifier: BSD-3-Clause
 """Parse specification extracted from NEXRAD ICD PDFs and generate Python code."""
 
-from __future__ import print_function
-
 import warnings
 
 

metpy/io/_tools.py

@@ -3,8 +3,6 @@
 # SPDX-License-Identifier: BSD-3-Clause
 """A collection of general purpose tools for reading files."""
 
-from __future__ import print_function
-
 import bz2
 from collections import namedtuple
 import gzip
@@ -14,14 +12,7 @@
 
 log = logging.getLogger(__name__)
 
-
-# This works around problems on early Python 2.7 where Struct.unpack_from() can't handle
-# being given a bytearray; use memoryview on Python 3, since calling bytearray again isn't
-# cheap.
-try:
-    bytearray_to_buff = buffer
-except NameError:
-    bytearray_to_buff = memoryview
+bytearray_to_buff = memoryview
 
 
 def open_as_needed(filename):

metpy/io/gini.py

@@ -2,14 +2,10 @@
 # Distributed under the terms of the BSD 3-Clause License.
 # SPDX-License-Identifier: BSD-3-Clause
 """Tools to process GINI-formatted products."""
-from __future__ import absolute_import
 
 import contextlib
 from datetime import datetime
-try:
-    from enum import Enum
-except ImportError:
-    from enum34 import Enum
+from enum import Enum
 from io import BytesIO
 from itertools import repeat  # noqa: I202
 import logging

metpy/io/nexrad.py

@@ -3,8 +3,6 @@
 # SPDX-License-Identifier: BSD-3-Clause
 """Support reading information from various NEXRAD formats."""
 
-from __future__ import print_function
-
 import bz2
 from collections import defaultdict, namedtuple, OrderedDict
 import contextlib
@@ -20,7 +18,6 @@
 
 from ._tools import (Array, BitField, Bits, bits_to_code, DictStruct, Enum, IOBuffer,
                      NamedStruct, open_as_needed, zlib_decompress_all_frames)
-from ..cbook import is_string_like
 from ..package_tools import Exporter
 
 exporter = Exporter(globals())
@@ -1539,7 +1536,7 @@ def __init__(self, filename):
 
         """
         fobj = open_as_needed(filename)
-        self.filename = filename if is_string_like(filename) else 'No File'
+        self.filename = filename if isinstance(filename, str) else 'No File'
 
         # Just read in the entire set of data at once
         with contextlib.closing(fobj):

metpy/pandas.py

@@ -2,8 +2,6 @@
 # Distributed under the terms of the BSD 3-Clause License.
 # SPDX-License-Identifier: BSD-3-Clause
 """Provide accessors to enhance interoperability between Pandas and MetPy."""
-from __future__ import absolute_import
-
 import functools
 import logging