Merge pull request gwpy#1222 from alurban/drop-six

Drop dependence on the six package and remove python < 3 workarounds

docs/conf.py

@@ -24,10 +24,9 @@
 import shutil
 import subprocess
 import warnings
+from configparser import (ConfigParser, NoOptionError)
 from string import Template
 
-from six.moves.configparser import (ConfigParser, NoOptionError)
-
 import matplotlib
 
 from sphinx.util import logging

docs/install/index.rst

@@ -59,7 +59,6 @@ GWpy has the following strict requirements:
    |numpy|_            ``>=1.12.0``
    |dateutil|_
    |scipy|_            ``>=1.2.0``
-   |six|_              ``>=1.5``
    |tqdm|_             ``>=4.10.0``
    ==================  ===========================
 

examples/test_examples.py

@@ -21,7 +21,6 @@
 
 import os
 import re
-import sys
 import warnings
 from contextlib import contextmanager
 from pathlib import Path
@@ -34,9 +33,6 @@
 
 __author__ = "Duncan Macleod <duncan.macleod@ligo.org>"
 
-if sys.version_info < (3, 6):  # python < 3.6
-    pytest.skip('example tests will only run on python >= 3.6',
-                allow_module_level=True)
 pytest.importorskip("matplotlib", minversion="2.2.0")
 
 use('agg')  # force non-interactive backend
@@ -59,11 +55,11 @@
 @contextmanager
 def cwd(path):
     oldpwd = Path.cwd()
-    os.chdir(path)
+    os.chdir(str(path))
     try:
         yield
     finally:
-        os.chdir(oldpwd)
+        os.chdir(str(oldpwd))
 
 
 @pytest.fixture(autouse=True)
@@ -84,8 +80,6 @@ def test_example(script):
     with cwd(script.parent):
         with script.open('r') as example:
             raw = example.read()
-        if not isinstance(raw, bytes):  # python < 3
-            raw = raw.encode('utf-8')
         code = compile(raw, str(script), "exec")
         try:
             exec(code, globals())

gwpy/cli/tests/test_gwpy_plot.py

@@ -20,10 +20,7 @@
 """
 
 from pathlib import Path
-try:
-    from unittest import mock
-except ImportError:  # python < 3
-    import mock
+from unittest import mock
 
 import pytest
 

gwpy/detector/channel.py

@@ -22,8 +22,7 @@
 import re
 from copy import copy
 from math import ceil
-
-from six.moves.urllib.parse import urlparse
+from urllib.parse import urlparse
 
 from astropy import units
 from astropy.io import registry as io_registry

gwpy/detector/io/clf.py

@@ -66,11 +66,9 @@
 """
 
 import re
+import configparser
 from collections import OrderedDict
 
-from six import string_types
-from six.moves import configparser
-
 from numpy import inf
 
 from ...io import registry
@@ -107,7 +105,7 @@ def read_channel_list_file(*source):
         if 'flow' in params or 'fhigh' in params:
             low = params.pop('flow', 0)
             high = params.pop('fhigh', inf)
-            if isinstance(high, string_types) and high.lower() == 'nyquist':
+            if isinstance(high, str) and high.lower() == 'nyquist':
                 high = inf
             frange = float(low), float(high)
         else:

gwpy/frequencyseries/hist.py

@@ -19,8 +19,6 @@
 """This module provides a spectral-variation histogram class
 """
 
-from six.moves import range
-
 import numpy
 
 from astropy.io import registry as io_registry

gwpy/io/cache.py

@@ -28,8 +28,6 @@
 from collections import (namedtuple, OrderedDict)
 from pathlib import Path
 
-from six import string_types
-
 from ..time import LIGOTimeGPS
 from .utils import (FILE_LIKE, file_path)
 
@@ -239,7 +237,7 @@ def write_cache(cache, fobj, format=None):
         - ``'ffl'`` : write an FFL-format cache
     """
     # open file
-    if isinstance(fobj, string_types):
+    if isinstance(fobj, str):
         with open(fobj, 'w') as fobj2:
             return write_cache(cache, fobj2, format=format)
 
@@ -274,7 +272,7 @@ def is_cache(cache):
         `True` if the input object is a cache, or a file in LAL cache format,
         otherwise `False`
     """
-    if isinstance(cache, string_types + FILE_LIKE):
+    if isinstance(cache, (str,) + FILE_LIKE):
         try:
             return bool(len(read_cache(cache)))
         except (TypeError, ValueError, UnicodeDecodeError, ImportError):

gwpy/io/datafind.py

@@ -39,9 +39,8 @@
 import re
 import warnings
 from functools import wraps
-
-from six.moves.http_client import HTTPException
-from six.moves.urllib.parse import urlparse
+from http.client import HTTPException
+from urllib.parse import urlparse
 
 from ligo.segments import (
     segment as LigoSegment,

gwpy/io/gwf.py

@@ -20,9 +20,7 @@
 """
 
 import warnings
-
-import six
-from six.moves.urllib.parse import urlparse
+from urllib.parse import urlparse
 
 import numpy
 
@@ -33,10 +31,7 @@
 __author__ = 'Duncan Macleod <duncan.macleod@ligo.org>'
 
 # first 4 bytes of any valid GWF file (see LIGO-T970130 §4.3.1)
-if six.PY2:
-    GWF_SIGNATURE = 'IGWD'
-else:
-    GWF_SIGNATURE = b'IGWD'
+GWF_SIGNATURE = b'IGWD'
 
 
 # -- i/o ----------------------------------------------------------------------

gwpy/io/kerberos.py

@@ -31,8 +31,6 @@
 import sys
 from collections import OrderedDict
 
-from six.moves import input
-
 from ..utils.shell import which
 
 __author__ = "Duncan Macleod <duncan.macleod@ligo.org>"

gwpy/io/ligolw.py

@@ -22,22 +22,14 @@
 an 'io' subdirectory of the containing directory for that class.
 """
 
+import builtins
 import os.path
 import re
 from contextlib import contextmanager
 from functools import wraps
 from importlib import import_module
 from numbers import Integral
 
-# note: because the "future" module provides a builtins namespace,
-# we need to do this the other way around compared to normal
-try:
-    import __builtin__ as builtins
-except ImportError:  # python >= 3
-    import builtins
-
-from six import string_types
-
 import numpy
 
 try:
@@ -415,7 +407,7 @@ def open_xmldoc(fobj, **kwargs):
     use_in(kwargs.setdefault('contenthandler', LIGOLWContentHandler))
 
     try:  # try and load existing file
-        if isinstance(fobj, string_types):
+        if isinstance(fobj, str):
             return load_filename(fobj, **kwargs)
         if isinstance(fobj, FILE_LIKE):
             return load_fileobj(fobj, **kwargs)[0]
@@ -530,7 +522,7 @@ def write_tables(target, tables, append=False, overwrite=False, **kwargs):
             target, contenthandler=kwargs.pop('contenthandler',
                                               LIGOLWContentHandler))
     # fail on existing document and not overwriting
-    elif (not overwrite and isinstance(target, string_types) and
+    elif (not overwrite and isinstance(target, str) and
           os.path.isfile(target)):
         raise IOError("File exists: {}".format(target))
     else:  # or create a new document
@@ -540,7 +532,7 @@ def write_tables(target, tables, append=False, overwrite=False, **kwargs):
     write_tables_to_document(xmldoc, tables, overwrite=overwrite)
 
     # write file
-    if isinstance(target, string_types):
+    if isinstance(target, str):
         kwargs.setdefault('gz', target.endswith('.gz'))
         ligolw_utils.write_filename(xmldoc, target, **kwargs)
     elif isinstance(target, FILE_LIKE):

gwpy/io/nds2.py

@@ -26,9 +26,7 @@
 import re
 import warnings
 from collections import OrderedDict
-from functools import wraps
-
-from six.moves import reduce
+from functools import (reduce, wraps)
 
 from ..time import to_gps
 from ..utils.enum import NumpyTypeEnum

gwpy/io/tests/test_datafind.py

@@ -20,12 +20,10 @@
 """
 
 import os
+from http.client import (HTTPConnection, HTTPException)
 from io import BytesIO
 from itertools import cycle
 
-import six
-from six.moves.http_client import (HTTPConnection, HTTPException)
-
 import pytest
 
 import gwdatafind
@@ -36,10 +34,7 @@
 
 __author__ = 'Duncan Macleod <duncan.macleod@ligo.org>'
 
-if six.PY2:
-    OPEN = '__builtin__.open'
-else:
-    OPEN = 'builtins.open'
+OPEN = 'builtins.open'
 
 # -- mock the environment -----------------------------------------------------
 

gwpy/io/tests/test_gwf.py

@@ -19,7 +19,7 @@
 """Unit tests for :mod:`gwpy.io.gwf`
 """
 
-from six.moves.urllib.parse import urljoin
+from urllib.parse import urljoin
 
 import pytest
 

gwpy/io/utils.py

@@ -21,24 +21,16 @@
 
 import gzip
 import tempfile
-
-from six import string_types
-from six.moves.urllib.parse import urlparse
+from urllib.parse import urlparse
 
 __author__ = 'Duncan Macleod <duncan.macleod@ligo.org>'
 
 # build list of file-like types
-try:  # python < 3
-    FILE_LIKE = (
-        file, gzip.GzipFile,
-        tempfile._TemporaryFileWrapper,  # pylint: disable=protected-access
-    )
-except NameError:  # python >= 3
-    from io import IOBase
-    FILE_LIKE = (
-        IOBase, gzip.GzipFile,
-        tempfile._TemporaryFileWrapper,  # pylint: disable=protected-access
-    )
+from io import IOBase
+FILE_LIKE = (
+    IOBase, gzip.GzipFile,
+    tempfile._TemporaryFileWrapper,  # pylint: disable=protected-access
+)
 
 GZIP_SIGNATURE = b'\x1f\x8b\x08'
 
@@ -64,7 +56,7 @@ def identify(origin, filepath, fileobj, *args, **kwargs):
         """Identify the given extensions in a file object/path
         """
         # pylint: disable=unused-argument
-        if (isinstance(filepath, string_types) and
+        if (isinstance(filepath, str) and
                 filepath.endswith(extensions)):
             return True
         return False
@@ -134,13 +126,13 @@ def file_list(flist):
         if the input `flist` cannot be interpreted as any of the above inputs
     """
     # open a cache file and return list of paths
-    if (isinstance(flist, string_types) and
+    if (isinstance(flist, str) and
             flist.endswith(('.cache', '.lcf', '.ffl'))):
         from .cache import read_cache
         return read_cache(flist)
 
     # separate comma-separate list of names
-    if isinstance(flist, string_types):
+    if isinstance(flist, str):
         return flist.split(',')
 
     # parse list of entries (of some format)
@@ -189,9 +181,9 @@ def file_path(fobj):
     >>> file_path("file:///home/user/test.txt")
     '/home/user/test.txt'
     """
-    if isinstance(fobj, string_types) and fobj.startswith("file:"):
+    if isinstance(fobj, str) and fobj.startswith("file:"):
         return urlparse(fobj).path
-    if isinstance(fobj, string_types):
+    if isinstance(fobj, str):
         return fobj
     if (isinstance(fobj, FILE_LIKE) and hasattr(fobj, "name")):
         return fobj.name

gwpy/plot/plot.py

@@ -22,12 +22,8 @@
 import itertools
 import importlib
 import warnings
-try:
-    from collections.abc import (KeysView, ValuesView)
-except ImportError:  # python < 3.3
-    from collections import (KeysView, ValuesView)
-
-from six.moves import zip_longest
+from collections.abc import (KeysView, ValuesView)
+from itertools import zip_longest
 
 import numpy
 

gwpy/segments/flag.py

@@ -35,13 +35,12 @@
 from io import BytesIO
 from collections import OrderedDict
 from copy import (copy as shallowcopy, deepcopy)
+from functools import reduce
 from math import (floor, ceil)
+from queue import Queue
 from threading import Thread
-
-from six.moves import reduce
-from six.moves.urllib.error import (URLError, HTTPError)
-from six.moves.urllib.parse import urlparse
-from six.moves.queue import Queue
+from urllib.error import (URLError, HTTPError)
+from urllib.parse import urlparse
 
 from numpy import inf