[commands] Fix flag annotations in 3.14 using annotationlib

Fix #10349

Author: Rapptz

discord/ext/commands/flags.py

@@ -50,6 +50,25 @@
     from .context import Context
     from .parameters import Parameter
 
+try:
+    from annotationlib import call_annotate_function, get_annotate_from_class_namespace  # type: ignore
+
+    def get_annotations_from_namespace(namespace: Dict[str, Any]) -> Dict[str, Any]:
+        # In Python 3.14, classes no longer get `__annotations__` and instead a function
+        # under __annotate__ is used instead that that takes a format argument on how to
+        # receive those annotations.
+        # Format 1 is full value, Format 3 is value and ForwardRef for undefined ones
+        # So format 3 is the one we're typically used to
+        annotate = get_annotate_from_class_namespace(namespace)
+        if annotate is not None:
+            return call_annotate_function(annotate, 3)  # type: ignore
+        return namespace.get('__annotations__', {})
+
+except ImportError:
+
+    def get_annotations_from_namespace(namespace: Dict[str, Any]) -> Dict[str, Any]:
+        return namespace.get('__annotations__', {})
+
 
 @dataclass
 class Flag:
@@ -177,15 +196,7 @@ def validate_flag_name(name: str, forbidden: Set[str]) -> None:
 
 
 def get_flags(namespace: Dict[str, Any], globals: Dict[str, Any], locals: Dict[str, Any]) -> Dict[str, Flag]:
-    annotations = namespace.get('__annotations__', {})
-    if '__annotate__' in namespace:
-        # In Python 3.14, classes no longer get `__annotations__` and instead a function
-        # under __annotate__ is used instead that that takes a format argument on how to
-        # receive those annotations.
-        # Format 1 is full value, Format 3 is value and ForwardRef for undefined ones
-        # So format 3 is the one we're typically used to
-        annotations = namespace['__annotate__'](3)
-
+    annotations = get_annotations_from_namespace(namespace)
     case_insensitive = namespace['__commands_flag_case_insensitive__']
     flags: Dict[str, Flag] = {}
     cache: Dict[str, Any] = {}