From 18e7e287ef143efb17d38ddab089a94989a5bbe9 Mon Sep 17 00:00:00 2001
From: Nyall Dawson <nyall.dawson@gmail.com>
Date: Fri, 7 Feb 2025 11:20:22 +1000
Subject: [PATCH] [pyprovider] Ignore unset attributes when changing attribute
 values

---
 tests/src/python/provider_python.py | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/tests/src/python/provider_python.py b/tests/src/python/provider_python.py
index ad6ab99e0f2..c0a8dfb0cbb 100644
--- a/tests/src/python/provider_python.py
+++ b/tests/src/python/provider_python.py
@@ -14,6 +14,7 @@ __date__ = "2018-03-18"
 __copyright__ = "Copyright 2018, The QGIS Project"
 
 from qgis.PyQt.QtCore import QVariant
+from qgis._core import QgsUnsetAttributeValue
 from qgis.core import (
     Qgis,
     QgsAbstractFeatureIterator,
@@ -34,6 +35,7 @@ from qgis.core import (
     QgsSpatialIndex,
     QgsVectorDataProvider,
     QgsVectorLayer,
+    QgsUnsetAttributeValue,
 )
 
 
@@ -421,6 +423,8 @@ class PyProvider(QgsVectorDataProvider):
             except KeyError:
                 continue
             for k, v in attrs.items():
+                if isinstance(v, QgsUnsetAttributeValue):
+                    continue
                 f.setAttribute(k, v)
         self.clearMinMaxCache()
         return True