Rmv circular import, create Has_id_attribute Protocol instead

2 files changed, 3 insertions, 5 deletions

diff --git a/git/objects/tree.py b/git/objects/tree.py
index 804554d8..e168c6c4 100644
--- a/git/objects/tree.py
+++ b/git/objects/tree.py
@@ -323,7 +323,7 @@ class Tree(IndexObject, diff.Diffable, util.Traversable, util.Serializable):
                     super(Tree, self).traverse(predicate, prune, depth,  # type: ignore
                                                branch_first, visit_once, ignore_self))
 
-    def list_traverse(self, *args: Any, **kwargs: Any) -> IterableList[Union['Tree', 'Submodule', 'Blob']]:
+    def list_traverse(self, *args: Any, **kwargs: Any) -> IterableList[IndexObjUnion]:
         return super(Tree, self).list_traverse(* args, **kwargs)
 
     # List protocol
diff --git a/git/objects/util.py b/git/objects/util.py
index 4dce0aee..1c266563 100644
--- a/git/objects/util.py
+++ b/git/objects/util.py
@@ -19,13 +19,11 @@ import time
 import calendar
 from datetime import datetime, timedelta, tzinfo
 
-from git.objects.base import IndexObject  # just for an isinstance check
-
 # typing ------------------------------------------------------------
 from typing import (Any, Callable, Deque, Iterator, NamedTuple, overload, Sequence,
                     TYPE_CHECKING, Tuple, Type, TypeVar, Union, cast)
 
-from git.types import Literal
+from git.types import Has_id_attribute, Literal
 
 if TYPE_CHECKING:
     from io import BytesIO, StringIO
@@ -319,7 +317,7 @@ class Traversable(object):
         """
         # Commit and Submodule have id.__attribute__ as IterableObj
         # Tree has id.__attribute__ inherited from IndexObject
-        if isinstance(self, (TraversableIterableObj, IndexObject)):
+        if isinstance(self, (TraversableIterableObj, Has_id_attribute)):
             id = self._id_attribute_
         else:
             id = ""     # shouldn't reach here, unless Traversable subclass created with no _id_attribute_