Replaced type(NotImplemented) and type(None)

`type(NotImplemented)` and `type(None)` have, respectively, been replaced with `types.NotImplementedType` and `types.NoneType`
python · gvanrossum · Sep 22, 2020 · Sep 18, 2020 · Sep 18, 2020 · Sep 18, 2020
commit 2791a239bacfe1f16e9672ca063cdb1f29e9a147
diff --git a/Lib/ast.py b/Lib/ast.py
@@ -572,7 +572,7 @@ def __new__(cls, *args, **kwargs):
     Num: (int, float, complex),
     Str: (str,),
     Bytes: (bytes,),
-    NameConstant: (type(None), bool),
+    NameConstant: (types.NoneType, bool),
     Ellipsis: (types.EllipsisType,),
 }
 _const_types_not = {
@@ -581,7 +581,7 @@ def __new__(cls, *args, **kwargs):
 
 _const_node_type_names = {
     bool: 'NameConstant',  # should be before int
-    type(None): 'NameConstant',
+    types.NoneType: 'NameConstant',
     int: 'Num',
     float: 'Num',
     complex: 'Num',

diff --git a/Lib/copy.py b/Lib/copy.py
@@ -106,10 +106,10 @@ def copy(x):
 
 def _copy_immutable(x):
     return x
-for t in (type(None), int, float, bool, complex, str, tuple,
+for t in (types.NoneType, int, float, bool, complex, str, tuple,
           bytes, frozenset, type, range, slice, property,
           types.BuiltinFunctionType, types.EllipsisType,
-          type(NotImplemented), types.FunctionType, weakref.ref):
+          types.NotImplementedType, types.FunctionType, weakref.ref):
     d[t] = _copy_immutable
 t = getattr(types, "CodeType", None)
 if t is not None:
@@ -181,9 +181,9 @@ def deepcopy(x, memo=None, _nil=[]):
 
 def _deepcopy_atomic(x, memo):
     return x
-d[type(None)] = _deepcopy_atomic
+d[types.NoneType] = _deepcopy_atomic
 d[types.EllipsisType] = _deepcopy_atomic
-d[type(NotImplemented)] = _deepcopy_atomic
+d[types.NotImplementedType] = _deepcopy_atomic
 d[int] = _deepcopy_atomic
 d[float] = _deepcopy_atomic
 d[bool] = _deepcopy_atomic

diff --git a/Lib/distutils/unixccompiler.py b/Lib/distutils/unixccompiler.py
@@ -13,7 +13,7 @@
   * link shared library handled by 'cc -shared'
 """
 
-import os, sys, re
+import os, sys, re, types
 
 from distutils import sysconfig
 from distutils.dep_util import newer
@@ -157,7 +157,7 @@ def link(self, target_desc, objects,
 
         lib_opts = gen_lib_options(self, library_dirs, runtime_library_dirs,
                                    libraries)
-        if not isinstance(output_dir, (str, type(None))):
+        if not isinstance(output_dir, (str, types.NoneType)):
             raise TypeError("'output_dir' must be a string or None")
         if output_dir is not None:
             output_filename = os.path.join(output_dir, output_filename)

diff --git a/Lib/idlelib/run.py b/Lib/idlelib/run.py
@@ -15,6 +15,7 @@
 import _thread as thread
 import threading
 import warnings
+import types
 
 from idlelib import autocomplete  # AutoComplete, fetch_encodings
 from idlelib import calltip  # Calltip
@@ -558,7 +559,7 @@ def runcode(self, code):
         except SystemExit as e:
             if e.args:  # SystemExit called with an argument.
                 ob = e.args[0]
-                if not isinstance(ob, (type(None), int)):
+                if not isinstance(ob, (types.NoneType, int)):
                     print('SystemExit: ' + str(ob), file=sys.stderr)
             # Return to the interactive prompt.
         except:

diff --git a/Lib/imp.py b/Lib/imp.py
@@ -264,7 +264,7 @@ def find_module(name, path=None):
     """
     if not isinstance(name, str):
         raise TypeError("'name' must be a str, not {}".format(type(name)))
-    elif not isinstance(path, (type(None), list)):
+    elif not isinstance(path, (types.NoneType, list)):
         # Backwards-compatibility
         raise RuntimeError("'path' must be None or a list, "
                            "not {}".format(type(path)))

diff --git a/Lib/inspect.py b/Lib/inspect.py
@@ -2034,7 +2034,7 @@ def wrap_value(s):
             except NameError:
                 raise RuntimeError()
 
-        if isinstance(value, (str, int, float, bytes, bool, type(None))):
+        if isinstance(value, (str, int, float, bytes, bool, types.NoneType)):
             return ast.Constant(value)
         raise RuntimeError()
 

diff --git a/Lib/lib2to3/fixes/fix_types.py b/Lib/lib2to3/fixes/fix_types.py
@@ -36,8 +36,6 @@
         'ListType': 'list',
         'LongType': 'int',
         'ObjectType' : 'object',
-        'NoneType': 'type(None)',
-        'NotImplementedType' : 'type(NotImplemented)',
         'SliceType' : 'slice',
         'StringType': 'bytes', # XXX ?
         'StringTypes' : '(str,)', # XXX ?

diff --git a/Lib/lib2to3/tests/test_fixers.py b/Lib/lib2to3/tests/test_fixers.py
@@ -3276,10 +3276,6 @@ def test_basic_types_convert(self):
         a = """int"""
         self.check(b, a)
 
-        b = """types.NoneType"""
-        a = """type(None)"""
-        self.check(b, a)
-
         b = "types.StringTypes"
         a = "(str,)"
         self.check(b, a)

diff --git a/Lib/pickle.py b/Lib/pickle.py
@@ -23,7 +23,7 @@
 
 """
 
-from types import FunctionType, EllipsisType
+import types
 from copyreg import dispatch_table
 from copyreg import _extension_registry, _inverted_registry, _extension_cache
 from itertools import islice
@@ -737,7 +737,7 @@ def save_reduce(self, func, args, state=None, listitems=None,
 
     def save_none(self, obj):
         self.write(NONE)
-    dispatch[type(None)] = save_none
+    dispatch[types.NoneType] = save_none
 
     def save_bool(self, obj):
         if self.proto >= 2:
@@ -1117,15 +1117,15 @@ def save_global(self, obj, name=None):
         self.memoize(obj)
 
     def save_type(self, obj):
-        if obj is type(None):
+        if obj is types.NoneType:
             return self.save_reduce(type, (None,), obj=obj)
-        elif obj is type(NotImplemented):
+        elif obj is types.NotImplementedType:
             return self.save_reduce(type, (NotImplemented,), obj=obj)
-        elif obj is EllipsisType:
+        elif obj is types.EllipsisType:
             return self.save_reduce(type, (...,), obj=obj)
         return self.save_global(obj)
 
-    dispatch[FunctionType] = save_global
+    dispatch[types.FunctionType] = save_global
     dispatch[type] = save_type
 
 

diff --git a/Lib/pickletools.py b/Lib/pickletools.py
@@ -15,6 +15,7 @@
 import pickle
 import re
 import sys
+import types
 
 __all__ = ['dis', 'genops', 'optimize']
 
@@ -1017,7 +1018,7 @@ def __repr__(self):
 
 pynone = StackObject(
     name="None",
-    obtype=type(None),
+    obtype=types.NoneType,
     doc="The Python None object.")
 
 pytuple = StackObject(

diff --git a/Lib/pprint.py b/Lib/pprint.py
@@ -591,7 +591,7 @@ def _safe_repr(object, context, maxlevels, level, sort_dicts):
     return rep, (rep and not rep.startswith('<')), False
 
 _builtin_scalars = frozenset({str, bytes, bytearray, int, float, complex,
-                              bool, type(None)})
+                              bool, _types.NoneType})
 
 def _recursion(object):
     return ("<Recursion on %s with id=%s>"

diff --git a/Lib/pydoc_data/topics.py b/Lib/pydoc_data/topics.py
@@ -1365,7 +1365,7 @@
                       'explicitly return a\n'
                       'value.  It supports no special operations.  There is '
                       'exactly one null\n'
-                      'object, named "None" (a built-in name).  "type(None)()" '
+                      'object, named "None" (a built-in name).  "types.NoneType()" '
                       'produces the\n'
                       'same singleton.\n'
                       '\n'

diff --git a/Lib/random.py b/Lib/random.py
@@ -55,6 +55,7 @@
 from bisect import bisect as _bisect
 import os as _os
 import _random
+import types
 
 try:
     # hashlib is pretty heavy to load, try lean internal module first
@@ -154,7 +155,7 @@ def seed(self, a=None, version=2):
             a += _sha512(a).digest()
             a = int.from_bytes(a, 'big')
 
-        elif not isinstance(a, (type(None), int, float, str, bytes, bytearray)):
+        elif not isinstance(a, (types.NoneType, int, float, str, bytes, bytearray)):
             _warn('Seeding based on hashing is deprecated\n'
                   'since Python 3.9 and will be removed in a subsequent '
                   'version. The only \n'

diff --git a/Lib/runpy.py b/Lib/runpy.py
@@ -261,7 +261,7 @@ def run_path(path_name, init_globals=None, run_name=None):
     if type(importer).__module__ == 'imp':
         if type(importer).__name__ == 'NullImporter':
             is_NullImporter = True
-    if isinstance(importer, type(None)) or is_NullImporter:
+    if isinstance(importer, types.NoneType) or is_NullImporter:
         # Not a valid sys.path entry, so run the code directly
         # execfile() doesn't help as we want to allow compiled files
         code, fname = _get_code_from_file(run_name, path_name)

diff --git a/Lib/sqlite3/test/userfunctions.py b/Lib/sqlite3/test/userfunctions.py
@@ -21,6 +21,7 @@
 #    misrepresented as being the original software.
 # 3. This notice may not be removed or altered from any source distribution.
 
+import types
 import unittest
 import unittest.mock
 import sqlite3 as sqlite
@@ -49,7 +50,7 @@ def func_isint(v):
 def func_isfloat(v):
     return type(v) is float
 def func_isnone(v):
-    return type(v) is type(None)
+    return type(v) is types.NoneType
 def func_isblob(v):
     return isinstance(v, (bytes, memoryview))
 def func_islonglong(v):
@@ -107,7 +108,7 @@ def __init__(self):
         self.val = None
 
     def step(self, whichType, val):
-        theType = {"str": str, "int": int, "float": float, "None": type(None),
+        theType = {"str": str, "int": int, "float": float, "None": types.NoneType,
                    "blob": bytes}
         self.val = int(theType[whichType] is type(val))
 
@@ -119,7 +120,7 @@ def __init__(self):
         self.val = 0
 
     def step(self, whichType, *vals):
-        theType = {"str": str, "int": int, "float": float, "None": type(None),
+        theType = {"str": str, "int": int, "float": float, "None": types.NoneType,
                    "blob": bytes}
         for val in vals:
             self.val += int(theType[whichType] is type(val))
@@ -211,7 +212,7 @@ def CheckFuncReturnNull(self):
         cur = self.con.cursor()
         cur.execute("select returnnull()")
         val = cur.fetchone()[0]
-        self.assertEqual(type(val), type(None))
+        self.assertEqual(type(val), types.NoneType)
         self.assertEqual(val, None)
 
     def CheckFuncReturnBlob(self):

diff --git a/Lib/test/test_dataclasses.py b/Lib/test/test_dataclasses.py
@@ -8,6 +8,7 @@
 import inspect
 import builtins
 import unittest
+import types
 from unittest.mock import Mock
 from typing import ClassVar, Any, List, Union, Tuple, Dict, Generic, TypeVar, Optional
 from typing import get_type_hints
@@ -2026,7 +2027,7 @@ class C:
     def test_docstring_one_field_with_default_none(self):
         @dataclass
         class C:
-            x: Union[int, type(None)] = None
+            x: Union[int, types.NoneType] = None
 
         self.assertDocStrEqual(C.__doc__, "C(x:Optional[int]=None)")
 
@@ -2955,7 +2956,7 @@ def test_text_annotations(self):
         self.assertEqual(
             get_type_hints(dataclass_textanno.Bar.__init__),
             {'foo': dataclass_textanno.Foo,
-             'return': type(None)})
+             'return': types.NoneType})
 
 
 class TestMakeDataclass(unittest.TestCase):

diff --git a/Lib/test/test_descr.py b/Lib/test/test_descr.py
@@ -3260,7 +3260,7 @@ class Int(int): __slots__ = []
         cant(2, bool)
         o = object()
         cant(o, type(1))
-        cant(o, type(None))
+        cant(o, types.NoneType)
         del o
         class G(object):
             __slots__ = ["a", "b"]
@@ -4000,35 +4000,35 @@ class D(C):
 
     def test_unsubclassable_types(self):
         with self.assertRaises(TypeError):
-            class X(type(None)):
+            class X(types.NoneType):
                 pass
         with self.assertRaises(TypeError):
-            class X(object, type(None)):
+            class X(object, types.NoneType):
                 pass
         with self.assertRaises(TypeError):
-            class X(type(None), object):
+            class X(types.NoneType, object):
                 pass
         class O(object):
             pass
         with self.assertRaises(TypeError):
-            class X(O, type(None)):
+            class X(O, types.NoneType):
                 pass
         with self.assertRaises(TypeError):
-            class X(type(None), O):
+            class X(types.NoneType, O):
                 pass
 
         class X(object):
             pass
         with self.assertRaises(TypeError):
-            X.__bases__ = type(None),
+            X.__bases__ = types.NoneType,
         with self.assertRaises(TypeError):
-            X.__bases__ = object, type(None)
+            X.__bases__ = object, types.NoneType
         with self.assertRaises(TypeError):
-            X.__bases__ = type(None), object
+            X.__bases__ = types.NoneType, object
         with self.assertRaises(TypeError):
-            X.__bases__ = O, type(None)
+            X.__bases__ = O, types.NoneType
         with self.assertRaises(TypeError):
-            X.__bases__ = type(None), O
+            X.__bases__ = types.NoneType, O
 
     def test_mutable_bases_with_failing_mro(self):
         # Testing mutable bases with failing mro...

diff --git a/Lib/test/test_getargs2.py b/Lib/test/test_getargs2.py
@@ -2,6 +2,7 @@
 import math
 import string
 import sys
+import types
 from test import support
 from test.support import import_helper
 # Skip this test if the _testcapi module isn't available.
@@ -567,11 +568,11 @@ def test_args(self):
 
         ret = get_args()
         self.assertIn(ret, ((), None))
-        self.assertIn(type(ret), (tuple, type(None)))
+        self.assertIn(type(ret), (tuple, types.NoneType))
 
         ret = get_args(*())
         self.assertIn(ret, ((), None))
-        self.assertIn(type(ret), (tuple, type(None)))
+        self.assertIn(type(ret), (tuple, types.NoneType))
 
     def test_tuple(self):
         from _testcapi import getargs_tuple
@@ -605,11 +606,11 @@ def test_kwargs(self):
 
         ret = get_kwargs()
         self.assertIn(ret, ({}, None))
-        self.assertIn(type(ret), (dict, type(None)))
+        self.assertIn(type(ret), (dict, types.NoneType))
 
         ret = get_kwargs(**{})
         self.assertIn(ret, ({}, None))
-        self.assertIn(type(ret), (dict, type(None)))
+        self.assertIn(type(ret), (dict, types.NoneType))
 
     def test_positional_args(self):
         # using all positional args

diff --git a/Lib/test/test_nntplib.py b/Lib/test/test_nntplib.py
@@ -9,6 +9,7 @@
 import os.path
 import re
 import threading
+import types
 
 from test import support
 from test.support import socket_helper
@@ -126,7 +127,7 @@ def _check_art_dict(self, art_dict):
              "references", ":bytes", ":lines"}
             )
         for v in art_dict.values():
-            self.assertIsInstance(v, (str, type(None)))
+            self.assertIsInstance(v, (str, types.NoneType))
 
     def test_xover(self):
         resp, count, first, last, name = self.server.group(self.GROUP_NAME)