1 files changed, 5 insertions, 0 deletions
diff --git a/lib/sqlalchemy/testing/entities.py b/lib/sqlalchemy/testing/entities.py
index cf3138835..15352c8c8 100644
--- a/lib/sqlalchemy/testing/entities.py
+++ b/lib/sqlalchemy/testing/entities.py
@@ -11,6 +11,7 @@ from __future__ import annotations
 
 import sqlalchemy as sa
 from .. import exc as sa_exc
+from ..orm.writeonly import WriteOnlyCollection
 
 _repr_stack = set()
 
@@ -82,8 +83,12 @@ class ComparableMixin:
             for attr in list(a.__dict__):
                 if attr.startswith("_"):
                     continue
+
                 value = getattr(a, attr)
 
+                if isinstance(value, WriteOnlyCollection):
+                    continue
+
                 try:
                     # handle lazy loader errors
                     battr = getattr(b, attr)