From c823ca38a92ee70001b9bddb2abd6b2b9b5b7c06 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?C=C3=A9dric=20Krier?= <ced@b2ck.com>
Date: Wed, 7 Jan 2026 08:29:45 +0100
Subject: [PATCH] Use only production inputs or outputs for lot trace

The production moves can not have any other traces than their sibling moves.

Closes #14385
---
 modules/production/stock.py | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/modules/production/stock.py b/modules/production/stock.py
index c81e8e83ff..9ef1025a28 100644
--- a/modules/production/stock.py
+++ b/modules/production/stock.py
@@ -206,13 +206,15 @@ class LotTrace(metaclass=PoolMeta):
             else_=document)
 
     def _get_upward_traces(self):
-        traces = super()._get_upward_traces()
         if self.production_input:
-            traces.update(self.production_input.outputs)
+            traces = set(self.production_input.outputs)
+        else:
+            traces = super()._get_upward_traces()
         return traces
 
     def _get_downward_traces(self):
-        traces = super()._get_downward_traces()
         if self.production_output:
-            traces.update(self.production_output.inputs)
+            traces = set(self.production_output.inputs)
+        else:
+            traces = super()._get_downward_traces()
         return traces