Create a reusable function to check Enum membership.

pylint/checkers/base/name_checker/checker.py

@@ -17,7 +17,7 @@
 from typing import TYPE_CHECKING, Tuple
 
 import astroid
-from astroid import nodes, util
+from astroid import nodes
 
 from pylint import constants, interfaces
 from pylint.checkers import utils
@@ -486,21 +486,10 @@ def visit_assignname(  # pylint: disable=too-many-branches
         # Check names defined in class scopes
         elif isinstance(frame, nodes.ClassDef):
             if not list(frame.local_attr_ancestors(node.name)):
-                for ancestor in frame.ancestors():
-                    is_enum_member = False
-                    if utils.is_enum(ancestor):
-                        enum_members = next(frame.igetattr("__members__"))
-                        if isinstance(enum_members, util.UninferableBase):
-                            continue
-                        is_enum_member = any(
-                            node.name == name_node.name
-                            for _, name_node in enum_members.items
-                        )
-                    if is_enum_member or utils.is_assign_name_annotated_with(
-                        node, "Final"
-                    ):
-                        self._check_name("class_const", node.name, node)
-                        break
+                if utils.is_enum_member(node) or utils.is_assign_name_annotated_with(
+                    node, "Final"
+                ):
+                    self._check_name("class_const", node.name, node)
                 else:
                     self._check_name("class_attribute", node.name, node)
 

pylint/checkers/utils.py

@@ -2246,3 +2246,22 @@ def clear_lru_caches() -> None:
     ]
     for lru in caches_holding_node_references:
         lru.cache_clear()
+
+
+def is_enum_member(node: nodes.AssignName) -> bool:
+    """Return `True` if `node` is an Enum member (is an item of the
+    `__members__` container).
+    """
+
+    frame = node.frame()
+    if not isinstance(frame, nodes.ClassDef) or not frame.is_subtype_of("enum.Enum"):
+        return False
+
+    enum_member_objects = next(frame.igetattr("__members__"))
+    try:
+        return node.name in [
+            name_obj.name for value, name_obj in enum_member_objects.items
+        ]
+    except TypeError:
+        # It is possible `enum_member_objects` is the `UninferableBase` object.
+        return False

tests/functional/i/invalid/invalid_name/invalid_name_enum.py

@@ -0,0 +1,21 @@
+
+""" Tests for invalid-name checker in the context of enums. """
+# pylint: disable=too-few-public-methods
+
+
+from enum import Enum
+
+
+class JustARegularClass:
+    """ No `invalid-name` by default for class attributes
+    """
+    apple = 42
+    orange = 24
+
+
+class EnumClass(Enum):
+    """ Members of a subclass of `enum.Enum` are expected to be UPPERCASE.
+    """
+    apple = 42  # [invalid-name]
+    orange = 24  # [invalid-name]
+    PEAR = 1

tests/functional/i/invalid/invalid_name/invalid_name_enum.txt

@@ -0,0 +1,2 @@
+invalid-name:19:4:19:9:EnumClass:"Class constant name ""apple"" doesn't conform to UPPER_CASE naming style":HIGH
+invalid-name:20:4:20:10:EnumClass:"Class constant name ""orange"" doesn't conform to UPPER_CASE naming style":HIGH