From 646b20f389ad14578a604b55efaa932fff61dd6d Mon Sep 17 00:00:00 2001
From: Muneeb Sheikh <muneikh@gmail.com>
Date: Sun, 11 Oct 2026 13:38:46 -0400
Subject: [PATCH] Allow same-key updates with duplicate conversion checks

---
 AUTHORS.rst      |  2 ++
 CHANGES.rst      |  2 ++
 box/box.py       |  2 +-
 test/test_box.py | 22 ++++++++++++++++++++++
 4 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/AUTHORS.rst b/AUTHORS.rst
index 6b44851..c981509 100644
--- a/AUTHORS.rst
+++ b/AUTHORS.rst
@@ -5,6 +5,8 @@ reporting, all input is greatly appreciated!
 
 Code contributions:
 
+- Muneeb Sheikh (muneikh)
+
 - Alexandre Decan (AlexandreDecan)
 - dhilipsiva (dhilipsiva)
 - MAA (FooBarQuaxx)
diff --git a/CHANGES.rst b/CHANGES.rst
index c4a347d..b45db98 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -4,6 +4,8 @@ Changelog
 Version 7.4.1
 -------------
 
+* Allow reassigning an existing key when duplicate conversion checks are enabled.
+
 * Fixing #303 Wrong version number (7.3.3) in 7.4.0 release (thanks to Michał Górny)
 
 Version 7.4.0
diff --git a/box/box.py b/box/box.py
index 8252643..0f73078 100644
--- a/box/box.py
+++ b/box/box.py
@@ -957,7 +957,7 @@ def _conversion_checks(self, item):
         """
         safe_item = self._safe_attr(item)
 
-        if safe_item in self._box_config["__safe_keys"]:
+        if safe_item in self._box_config["__safe_keys"] and self._box_config["__safe_keys"][safe_item] != item:
             dups = [f"{item}({safe_item})", f'{self._box_config["__safe_keys"][safe_item]}({safe_item})']
             if self._box_config["box_duplicates"].startswith("warn"):
                 warnings.warn(f"Duplicate conversion attributes exist: {dups}", BoxWarning)
diff --git a/test/test_box.py b/test/test_box.py
index e5c56e0..f278f3d 100644
--- a/test/test_box.py
+++ b/test/test_box.py
@@ -7,6 +7,7 @@
 import pickle
 import platform
 import shutil
+import warnings
 from multiprocessing import Queue
 from pathlib import Path
 from io import StringIO
@@ -28,6 +29,7 @@
 from ruamel.yaml import YAML
 
 from box import Box, BoxError, BoxKeyError, BoxList, ConfigBox, SBox, DDBox
+from box.exceptions import BoxWarning
 from box.box import _get_dot_paths, _camel_killer, _recursive_tuples  # type: ignore
 from box.converters import BOX_PARAMETERS
 
@@ -630,6 +632,26 @@ def test_duplicate_errors(self):
         with pytest.raises(BoxError):
             my_box["^a"] = 3
 
+    @pytest.mark.parametrize("policy", ["error", "warn"])
+    @pytest.mark.parametrize("use_attribute", [False, True])
+    def test_duplicate_checks_allow_reassigning_same_key(self, policy, use_attribute):
+        my_box = Box({"a b": 1}, box_duplicates=policy)
+        with warnings.catch_warnings():
+            warnings.simplefilter("error", BoxWarning)
+            if use_attribute:
+                my_box.a_b = 2
+            else:
+                my_box["a b"] = 2
+        assert my_box.to_dict() == {"a b": 2}
+        assert my_box.a_b == 2
+        if policy == "error":
+            with pytest.raises(BoxError):
+                my_box["a-b"] = 3
+            assert my_box.to_dict() == {"a b": 2}
+        else:
+            with pytest.warns(BoxWarning):
+                my_box["a-b"] = 3
+
     def test_copy(self):
         my_box = Box(movie_data, camel_killer_box=True)
         bb = my_box.copy()