From 2cec84620786fb31b8a14652508e876095ee7043 Mon Sep 17 00:00:00 2001
From: Emmanuel Garette <egarette@silique.fr>
Date: Mon, 9 Mar 2026 14:06:44 +0100
Subject: [PATCH] fix: copy object before modify namespace

---
 src/rougail/convert/convert.py | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/src/rougail/convert/convert.py b/src/rougail/convert/convert.py
index 2d38322c4..4e39e85b7 100644
--- a/src/rougail/convert/convert.py
+++ b/src/rougail/convert/convert.py
@@ -936,13 +936,17 @@ class ParserVariable:
 
     def change_namespaces(self, variable):
         for key, value in variable.items():
-            if isinstance(value, Calculation):
-                value.namespace = self.namespace
+            if isinstance(value, Calculation) and value.namespace != self.namespace:
+                copy = value.copy()
+                variable[key] = copy
+                copy.namespace = self.namespace
             if not isinstance(value, list):
                 continue
             for idx, val in enumerate(value):
-                if isinstance(val, Calculation):
-                    val.namespace = self.namespace
+                if isinstance(val, Calculation) and val.namespace != self.namespace:
+                    copy = val.copy()
+                    value[idx] = copy
+                    copy.namespace = self.namespace
 
     def del_family(
         self,