Use default values for annotate functions' __globals__, __builtins__, __defaults__, and __kwdefaults__

Author: dr-carlos

Lib/annotationlib.py

@@ -711,6 +711,9 @@ def call_annotate_function(annotate, format, *, owner=None, _is_evaluate=False):
         return annotate(format)
     except NotImplementedError:
         pass
+
+    annotate_defaults = getattr(annotate, "__defaults__", None)
+    annotate_kwdefaults = getattr(annotate, "__kwdefaults__", None)
     if format == Format.STRING:
         # STRING is implemented by calling the annotate function in a special
         # environment where every name lookup results in an instance of _Stringifier.
@@ -740,8 +743,8 @@ def call_annotate_function(annotate, format, *, owner=None, _is_evaluate=False):
             annotate.__code__,
             globals,
             closure=closure,
-            argdefs=annotate.__defaults__,
-            kwdefaults=annotate.__kwdefaults__,
+            argdefs=annotate_defaults,
+            kwdefaults=annotate_kwdefaults,
         )
         annos = func(Format.VALUE_WITH_FAKE_GLOBALS)
         if _is_evaluate:
@@ -768,11 +771,12 @@ def call_annotate_function(annotate, format, *, owner=None, _is_evaluate=False):
         # reconstruct the source. But in the dictionary that we eventually return, we
         # want to return objects with more user-friendly behavior, such as an __eq__
         # that returns a bool and an defined set of attributes.
-        namespace = {**annotate.__builtins__, **annotate.__globals__}
+        annotate_globals = getattr(annotate, "__globals__", {})
+        namespace = {**getattr(annotate, "__builtins__", builtins.__dict__), **annotate_globals}
         is_class = isinstance(owner, type)
         globals = _StringifierDict(
             namespace,
-            globals=annotate.__globals__,
+            globals=annotate_globals,
             owner=owner,
             is_class=is_class,
             format=format,
@@ -784,8 +788,8 @@ def call_annotate_function(annotate, format, *, owner=None, _is_evaluate=False):
             annotate.__code__,
             globals,
             closure=closure,
-            argdefs=annotate.__defaults__,
-            kwdefaults=annotate.__kwdefaults__,
+            argdefs=annotate_defaults,
+            kwdefaults=annotate_kwdefaults,
         )
         try:
             result = func(Format.VALUE_WITH_FAKE_GLOBALS)
@@ -802,7 +806,7 @@ def call_annotate_function(annotate, format, *, owner=None, _is_evaluate=False):
         # a value in certain cases where an exception gets raised during evaluation.
         globals = _StringifierDict(
             {},
-            globals=annotate.__globals__,
+            globals=annotate_globals,
             owner=owner,
             is_class=is_class,
             format=format,
@@ -814,8 +818,8 @@ def call_annotate_function(annotate, format, *, owner=None, _is_evaluate=False):
             annotate.__code__,
             globals,
             closure=closure,
-            argdefs=annotate.__defaults__,
-            kwdefaults=annotate.__kwdefaults__,
+            argdefs=annotate_defaults,
+            kwdefaults=annotate_kwdefaults,
         )
         result = func(Format.VALUE_WITH_FAKE_GLOBALS)
         globals.transmogrify(cell_dict)