[Python-checkins] bpo-45280: Add test for empty `NamedTuple` in `test_typing` (GH-28559)

[ambv]

https://github.com/python/cpython/commit/f56268a2cd38b3fe2be1e4361d3d8b581e73559b
commit: f56268a2cd38b3fe2be1e4361d3d8b581e73559b
branch: main
author: Nikita Sobolev <mail at sobolevn.me>
committer: ambv <lukasz at langa.pl>
date: 2021-09-26T18:32:18+02:00
summary:

bpo-45280: Add test for empty `NamedTuple` in `test_typing` (GH-28559)

Co-authored-by: Dong-hee Na <donghee.na92 at gmail.com>

files:
A Misc/NEWS.d/next/Tests/2021-09-25-11-05-31.bpo-45280.3MA6lC.rst
M Lib/test/test_typing.py

diff --git a/Lib/test/test_typing.py b/Lib/test/test_typing.py
index d1887f7eee443..38397a07e5717 100644
--- a/Lib/test/test_typing.py
+++ b/Lib/test/test_typing.py
@@ -4115,6 +4115,19 @@ def test_namedtuple_special_keyword_names(self):
         self.assertEqual(a.typename, 'foo')
         self.assertEqual(a.fields, [('bar', tuple)])
 
+    def test_empty_namedtuple(self):
+        NT = NamedTuple('NT')
+
+        class CNT(NamedTuple):
+            pass  # empty body
+
+        for struct in [NT, CNT]:
+            with self.subTest(struct=struct):
+                self.assertEqual(struct._fields, ())
+                self.assertEqual(struct._field_defaults, {})
+                self.assertEqual(struct.__annotations__, {})
+                self.assertIsInstance(struct(), struct)
+
     def test_namedtuple_errors(self):
         with self.assertRaises(TypeError):
             NamedTuple.__new__()
diff --git a/Misc/NEWS.d/next/Tests/2021-09-25-11-05-31.bpo-45280.3MA6lC.rst b/Misc/NEWS.d/next/Tests/2021-09-25-11-05-31.bpo-45280.3MA6lC.rst
new file mode 100644
index 0000000000000..71691f5ba2b89
--- /dev/null
+++ b/Misc/NEWS.d/next/Tests/2021-09-25-11-05-31.bpo-45280.3MA6lC.rst
@@ -0,0 +1 @@
+Add a test case for empty :class:`typing.NamedTuple`.