diff --git a/lib/eval_actions.py b/lib/eval_actions.py
index c84659c..dba5353 100644
--- a/lib/eval_actions.py
+++ b/lib/eval_actions.py
@@ -167,10 +167,10 @@ async def dispose_rejected_pr(conn, pr_number: int, eval_attempts: int, all_issu
                 )
                 diff = None
 
-            if diff is None:
-                # Conservative: fall through to attempt-count branches below
+            if not diff:
+                # None or empty — conservative fallback, fall through to attempt-count branches
                 pass
-            elif diff and "new file mode" not in diff:
+            elif "new file mode" not in diff:
                 logger.info(
                     "PR #%d: near_duplicate but modifies-only (enrichment) — skipping auto-close",
                     pr_number,