CLN: Misc PY2/3 compat functions (#26008)

Author: mroeschke

pandas/compat/__init__.py

@@ -8,7 +8,6 @@
 * lists: lrange(), lmap(), lzip(), lfilter()
 * iterable method compatibility: iteritems, iterkeys, itervalues
   * Uses the original method if available, otherwise uses items, keys, values.
-* bind_method: binds functions to classes
 * add_metaclass(metaclass) - class decorator that recreates class with with the
   given metaclass instead (and avoids intermediary class creation)
 
@@ -22,7 +21,6 @@
 from distutils.version import LooseVersion
 import sys
 import platform
-import types
 import struct
 
 PY2 = sys.version_info[0] == 2
@@ -32,8 +30,6 @@
 PY37 = sys.version_info >= (3, 7)
 PYPY = platform.python_implementation() == 'PyPy'
 
-from pandas.compat.chainmap import DeepChainMap
-
 
 # list-producing versions of the major Python iterating functions
 def lrange(*args, **kwargs):
@@ -52,29 +48,6 @@ def lfilter(*args, **kwargs):
     return list(filter(*args, **kwargs))
 
 
-if PY3:
-    def isidentifier(s):
-        return s.isidentifier()
-
-    def str_to_bytes(s, encoding=None):
-        return s.encode(encoding or 'ascii')
-
-    def bytes_to_str(b, encoding=None):
-        return b.decode(encoding or 'utf-8')
-
-else:
-    # Python 2
-    _name_re = re.compile(r"[a-zA-Z_][a-zA-Z0-9_]*$")
-
-    def isidentifier(s, dotted=False):
-        return bool(_name_re.match(s))
-
-    def str_to_bytes(s, encoding='ascii'):
-        return s
-
-    def bytes_to_str(b, encoding='ascii'):
-        return b
-
 if PY2:
     def iteritems(obj, **kw):
         return obj.iteritems(**kw)
@@ -95,30 +68,6 @@ def iterkeys(obj, **kw):
     def itervalues(obj, **kw):
         return iter(obj.values(**kw))
 
-
-def bind_method(cls, name, func):
-    """Bind a method to class, python 2 and python 3 compatible.
-
-    Parameters
-    ----------
-
-    cls : type
-        class to receive bound method
-    name : basestring
-        name of method on class instance
-    func : function
-        function to be bound as method
-
-
-    Returns
-    -------
-    None
-    """
-    # only python 2 has bound/unbound method issue
-    if not PY3:
-        setattr(cls, name, types.MethodType(func, None, cls))
-    else:
-        setattr(cls, name, func)
 # ----------------------------------------------------------------------------
 # functions largely based / taken from the six module
 
@@ -133,7 +82,7 @@ def to_str(s):
         Convert bytes and non-string into Python 3 str
         """
         if isinstance(s, bytes):
-            s = bytes_to_str(s)
+            s = s.decode('utf-8')
         elif not isinstance(s, str):
             s = str(s)
         return s
@@ -172,6 +121,7 @@ def wrapper(cls):
         return metaclass(cls.__name__, cls.__bases__, orig_vars)
     return wrapper
 
+
 if PY3:
     def raise_with_traceback(exc, traceback=Ellipsis):
         if traceback == Ellipsis:
@@ -207,6 +157,7 @@ def raise_with_traceback(exc, traceback=Ellipsis):
 else:
     re_type = type(re.compile(''))
 
+
 # https://github.com/pandas-dev/pandas/pull/9123
 def is_platform_little_endian():
     """ am I little endian """

pandas/core/computation/pytables.py

@@ -6,7 +6,7 @@
 import numpy as np
 
 from pandas._libs.tslibs import Timedelta, Timestamp
-from pandas.compat import DeepChainMap
+from pandas.compat.chainmap import DeepChainMap
 
 from pandas.core.dtypes.common import is_list_like
 

pandas/core/computation/scope.py

@@ -13,7 +13,7 @@
 import numpy as np
 
 from pandas._libs.tslibs import Timestamp
-from pandas.compat import DeepChainMap
+from pandas.compat.chainmap import DeepChainMap
 
 from pandas.core.base import StringMixin
 import pandas.core.computation as compu

pandas/core/generic.py

@@ -16,7 +16,7 @@
 
 from pandas._libs import Timestamp, iNaT, properties
 import pandas.compat as compat
-from pandas.compat import isidentifier, lrange, lzip, set_function_name, to_str
+from pandas.compat import lrange, lzip, set_function_name, to_str
 from pandas.compat.numpy import function as nv
 from pandas.errors import AbstractMethodError
 from pandas.util._decorators import (
@@ -5150,7 +5150,7 @@ def _dir_additions(self):
         If info_axis is a MultiIndex, it's first level values are used.
         """
         additions = {c for c in self._info_axis.unique(level=0)[:100]
-                     if isinstance(c, str) and isidentifier(c)}
+                     if isinstance(c, str) and c.isidentifier()}
         return super(NDFrame, self)._dir_additions().union(additions)
 
     # ----------------------------------------------------------------------

pandas/core/ops.py

@@ -12,7 +12,6 @@
 
 from pandas._libs import algos as libalgos, lib, ops as libops
 import pandas.compat as compat
-from pandas.compat import bind_method
 from pandas.errors import NullFrequencyError
 from pandas.util._decorators import Appender
 
@@ -1545,7 +1544,7 @@ def add_methods(cls, new_methods):
         force = not (issubclass(cls, ABCSparseArray) and
                      name.startswith('__i'))
         if force or name not in cls.__dict__:
-            bind_method(cls, name, method)
+            setattr(cls, name, method)
 
 
 # ----------------------------------------------------------------------

pandas/io/clipboards.py

@@ -2,8 +2,6 @@
 from io import StringIO
 import warnings
 
-import pandas.compat as compat
-
 from pandas.core.dtypes.generic import ABCDataFrame
 
 from pandas import get_option, option_context
@@ -38,10 +36,8 @@ def read_clipboard(sep=r'\s+', **kwargs):  # pragma: no cover
 
     # Try to decode (if needed, as "text" might already be a string here).
     try:
-        text = compat.bytes_to_str(
-            text, encoding=(kwargs.get('encoding') or
-                            get_option('display.encoding'))
-        )
+        text = text.decode(kwargs.get('encoding')
+                           or get_option('display.encoding'))
     except AttributeError:
         pass
 

pandas/io/common.py

@@ -16,7 +16,6 @@
 from urllib.request import pathname2url, urlopen
 import zipfile
 
-import pandas.compat as compat
 from pandas.errors import (  # noqa
     AbstractMethodError, DtypeWarning, EmptyDataError, ParserError,
     ParserWarning)
@@ -460,7 +459,7 @@ def __next__(self):
 
         # readline returns bytes, not str, but Python's CSV reader
         # expects str, so convert the output to str before continuing
-        newline = compat.bytes_to_str(newline)
+        newline = newline.decode('utf-8')
 
         # mmap doesn't raise if reading past the allocated
         # data but instead returns an empty string, so raise

pandas/tests/io/formats/test_printing.py

@@ -5,7 +5,6 @@
 import pandas._config.config as cf
 
 import pandas as pd
-from pandas import compat
 
 import pandas.io.formats.format as fmt
 import pandas.io.formats.printing as printing
@@ -27,7 +26,7 @@ def test_repr_binary_type():
         raw = bytes(letters, encoding=cf.get_option('display.encoding'))
     except TypeError:
         raw = bytes(letters)
-    b = str(compat.bytes_to_str(raw))
+    b = str(raw.decode('utf-8'))
     res = printing.pprint_thing(b, quote_strings=True)
     assert res == repr(b)
     res = printing.pprint_thing(b, quote_strings=False)

pandas/tests/io/json/test_ujson.py

@@ -654,7 +654,7 @@ def test_decode_big_escape(self):
         # Make sure no Exception is raised.
         for _ in range(10):
             base = '\u00e5'.encode("utf-8")
-            quote = compat.str_to_bytes("\"")
+            quote = b'"'
 
             escape_input = quote + (base * 1024 * 1024 * 2) + quote
             ujson.decode(escape_input)

pandas/tests/series/test_api.py

@@ -8,7 +8,7 @@
 import pytest
 
 import pandas.compat as compat
-from pandas.compat import isidentifier, lzip
+from pandas.compat import lzip
 
 import pandas as pd
 from pandas import (
@@ -282,7 +282,7 @@ def test_index_tab_completion(self, index):
         for i, x in enumerate(s.index.unique(level=0)):
             if i < 100:
                 assert (not isinstance(x, str) or
-                        not isidentifier(x) or x in dir_s)
+                        not x.isidentifier() or x in dir_s)
             else:
                 assert x not in dir_s