From 944917c76287fd178353ea4ee76e014fd21a40d7 Mon Sep 17 00:00:00 2001
From: frmdstryr <frmdstryr@protonmail.com>
Date: Fri, 1 May 2026 08:42:16 -0400
Subject: [PATCH] Handle errors in range_handler comparisons

---
 atom/src/validatebehavior.cpp | 18 ++++++++++++++++--
 tests/test_validators.py      | 25 +++++++++++++++++++++++++
 2 files changed, 41 insertions(+), 2 deletions(-)

diff --git a/atom/src/validatebehavior.cpp b/atom/src/validatebehavior.cpp
index 8c3584b2..e6da684b 100644
--- a/atom/src/validatebehavior.cpp
+++ b/atom/src/validatebehavior.cpp
@@ -881,23 +881,37 @@ range_handler( Member* member, CAtom* atom, PyObject* oldvalue, PyObject* newval
     PyObject* high = PyTuple_GET_ITEM( member->validate_context, 1 );
     if( low != Py_None )
     {
-        if( PyObject_RichCompareBool( low , newvalue, Py_GT ) )
+        switch (PyObject_RichCompareBool( low , newvalue, Py_GT ))
+        {
+        case 0:
+            break;
+        case 1:
             return  PyErr_Format(
                 PyExc_ValueError,
                 "range value for '%s' of '%s' too small",
                 PyUnicode_AsUTF8( member->name ),
                 Py_TYPE( pyobject_cast( atom ) )->tp_name
             );
+        default:
+            return 0;
+        }
     }
     if( high != Py_None )
     {
-        if( PyObject_RichCompareBool( high , newvalue, Py_LT ) )
+        switch( PyObject_RichCompareBool( high , newvalue, Py_LT ) )
+        {
+        case 0:
+            break;
+        case 1:
             return  PyErr_Format(
                 PyExc_ValueError,
                 "range value for '%s' of '%s' too large",
                 PyUnicode_AsUTF8( member->name ),
                 Py_TYPE( pyobject_cast( atom ) )->tp_name
             );
+        default:
+            return 0;
+        }
     }
     return cppy::incref( newvalue );
 }
diff --git a/tests/test_validators.py b/tests/test_validators.py
index c178c81d..53d37ca2 100644
--- a/tests/test_validators.py
+++ b/tests/test_validators.py
@@ -434,3 +434,28 @@ def test_custom_validate(mode, factory):
     with pytest.raises(TypeError) as excinfo:
         type(v).v.set_validate_mode(getattr(Validate, mode), 1)
     assert "str" in excinfo.exconly()
+
+
+def test_validate_range_error():
+    class CustomInt(int):
+        def __gt__(self, other):
+            raise TypeError("Cannot be compared")
+
+        def __lt__(self, other):
+            raise TypeError("Cannot be compared")
+
+    class Obj(Atom):
+        x = Range(low=0)
+        y = Range(high=10)
+
+    o = Obj()
+    o.x = 1
+    o.y = 9
+    with pytest.raises(ValueError):
+        o.x = -1
+    with pytest.raises(ValueError):
+        o.y = 11
+    with pytest.raises(TypeError):
+        o.x = CustomInt(-1)
+    with pytest.raises(TypeError):
+        o.y = CustomInt(11)