bpo-40182: Remove the _field_types attribute of the NamedTuple class (GH-19368)

2 files changed, 4 insertions, 8 deletions

diff --git a/Lib/test/test_typing.py b/Lib/test/test_typing.py
index 3a0edb9..dea09eb 100644
--- a/Lib/test/test_typing.py
+++ b/Lib/test/test_typing.py
@@ -3561,7 +3561,6 @@ class NamedTupleTests(BaseTestCase):
         self.assertEqual(Emp._fields, ('name', 'id'))
         self.assertEqual(Emp.__annotations__,
                          collections.OrderedDict([('name', str), ('id', int)]))
-        self.assertIs(Emp._field_types, Emp.__annotations__)
 
     def test_namedtuple_pyversion(self):
         if sys.version_info[:2] < (3, 6):
@@ -3581,7 +3580,6 @@ class NamedTupleTests(BaseTestCase):
         self.assertEqual(CoolEmployee._fields, ('name', 'cool'))
         self.assertEqual(CoolEmployee.__annotations__,
                          collections.OrderedDict(name=str, cool=int))
-        self.assertIs(CoolEmployee._field_types, CoolEmployee.__annotations__)
 
     def test_annotation_usage_with_default(self):
         jelle = CoolEmployeeWithDefault('Jelle')
@@ -3594,7 +3592,8 @@ class NamedTupleTests(BaseTestCase):
 
         self.assertEqual(CoolEmployeeWithDefault.__name__, 'CoolEmployeeWithDefault')
         self.assertEqual(CoolEmployeeWithDefault._fields, ('name', 'cool'))
-        self.assertEqual(CoolEmployeeWithDefault._field_types, dict(name=str, cool=int))
+        self.assertEqual(CoolEmployeeWithDefault.__annotations__,
+                         dict(name=str, cool=int))
         self.assertEqual(CoolEmployeeWithDefault._field_defaults, dict(cool=0))
 
         with self.assertRaises(TypeError):
@@ -3641,7 +3640,6 @@ class XMethBad2(NamedTuple):
         self.assertEqual(LocalEmployee.__name__, 'LocalEmployee')
         self.assertEqual(LocalEmployee._fields, ('name', 'age'))
         self.assertEqual(LocalEmployee.__annotations__, dict(name=str, age=int))
-        self.assertIs(LocalEmployee._field_types, LocalEmployee.__annotations__)
         with self.assertRaises(TypeError):
             NamedTuple('Name', [('x', int)], y=str)
         with self.assertRaises(TypeError):
diff --git a/Lib/typing.py b/Lib/typing.py
index 99355d0..a72003a 100644
--- a/Lib/typing.py
+++ b/Lib/typing.py
@@ -1705,9 +1705,7 @@ def _make_nmtuple(name, types):
     msg = "NamedTuple('Name', [(f0, t0), (f1, t1), ...]); each t must be a type"
     types = [(n, _type_check(t, msg)) for n, t in types]
     nm_tpl = collections.namedtuple(name, [n for n, t in types])
-    # Prior to PEP 526, only _field_types attribute was assigned.
-    # Now __annotations__ are used and _field_types is deprecated (remove in 3.9)
-    nm_tpl.__annotations__ = nm_tpl._field_types = dict(types)
+    nm_tpl.__annotations__ = dict(types)
     try:
         nm_tpl.__module__ = sys._getframe(2).f_globals.get('__name__', '__main__')
     except (AttributeError, ValueError):
@@ -1717,7 +1715,7 @@ def _make_nmtuple(name, types):
 
 # attributes prohibited to set in NamedTuple class syntax
 _prohibited = {'__new__', '__init__', '__slots__', '__getnewargs__',
-               '_fields', '_field_defaults', '_field_types',
+               '_fields', '_field_defaults',
                '_make', '_replace', '_asdict', '_source'}
 
 _special = {'__module__', '__name__', '__annotations__'}