gh-82129: Provide __annotate__ method for dataclasses from make_dataclass

Lib/dataclasses.py

@@ -1527,10 +1527,11 @@ class C(Base):
     seen = set()
     annotations = {}
     defaults = {}
+    any_marker = object()
     for item in fields:
         if isinstance(item, str):
             name = item
-            tp = 'typing.Any'
+            tp = any_marker
         elif len(item) == 2:
             name, tp, = item
         elif len(item) == 3:
@@ -1549,11 +1550,22 @@ class C(Base):
         seen.add(name)
         annotations[name] = tp
 
+    def annotate_method(format):
+        from typing import Any, _convert_to_source
+        ann_dict = {
+            ann: Any if t is any_marker else t
+            for ann, t in annotations.items()
+        }
+        if format == 1 or format == 2:
+            return ann_dict
+        else:
+            return _convert_to_source(ann_dict)
+
     # Update 'ns' with the user-supplied namespace plus our calculated values.
     def exec_body_callback(ns):
+        ns['__annotate__'] = annotate_method
         ns.update(namespace)
         ns.update(defaults)
-        ns['__annotations__'] = annotations
 
     # We use `types.new_class()` instead of simply `type()` to allow dynamic creation
     # of generic dataclasses.

Lib/test/test_dataclasses/__init__.py

@@ -4159,16 +4159,34 @@ def test_no_types(self):
         C = make_dataclass('Point', ['x', 'y', 'z'])
         c = C(1, 2, 3)
         self.assertEqual(vars(c), {'x': 1, 'y': 2, 'z': 3})
-        self.assertEqual(C.__annotations__, {'x': 'typing.Any',
-                                             'y': 'typing.Any',
-                                             'z': 'typing.Any'})
+        self.assertEqual(C.__annotations__, {'x': typing.Any,
+                                             'y': typing.Any,
+                                             'z': typing.Any})
 
         C = make_dataclass('Point', ['x', ('y', int), 'z'])
         c = C(1, 2, 3)
         self.assertEqual(vars(c), {'x': 1, 'y': 2, 'z': 3})
-        self.assertEqual(C.__annotations__, {'x': 'typing.Any',
+        self.assertEqual(C.__annotations__, {'x': typing.Any,
                                              'y': int,
-                                             'z': 'typing.Any'})
+                                             'z': typing.Any})
+
+    def test_no_types_get_annotations(self):
+        from annotationlib import Format, get_annotations
+
+        C = make_dataclass('C', ['x', ('y', int), 'z'])
+
+        self.assertEqual(
+            get_annotations(C, format=Format.VALUE),
+            {'x': typing.Any, 'y': int, 'z': typing.Any},
+        )
+        self.assertEqual(
+            get_annotations(C, format=Format.FORWARDREF),
+            {'x': typing.Any, 'y': int, 'z': typing.Any},
+        )
+        self.assertEqual(
+            get_annotations(C, format=Format.SOURCE),
+            {'x': 'typing.Any', 'y': 'int', 'z': 'typing.Any'},
+        )
 
     def test_module_attr(self):
         self.assertEqual(ByMakeDataClass.__module__, __name__)

Misc/NEWS.d/next/Library/2024-09-18-09-15-40.gh-issue-82129.GQwt3u.rst

@@ -0,0 +1,3 @@
+Fix :exc:`NameError` happenning on :func:`dataclasses.dataclass` created by
+:func:`dataclasses.make_dataclass` with un-annotated fields when
+:func:`typing.get_type_hints` was called on it.