Issue #26202: copy.deepcopy() now correctly copies range() objects with

non-atomic attributes.

Lib/copy.py

@@ -207,7 +207,6 @@ def _deepcopy_atomic(x, memo):
 except AttributeError:
     pass
 d[type] = _deepcopy_atomic
-d[range] = _deepcopy_atomic
 d[types.BuiltinFunctionType] = _deepcopy_atomic
 d[types.FunctionType] = _deepcopy_atomic
 d[weakref.ref] = _deepcopy_atomic

Lib/test/test_copy.py

@@ -314,7 +314,7 @@ def f():
             pass
         tests = [None, 42, 2**100, 3.14, True, False, 1j,
                  "hello", "hello\u1234", f.__code__,
-                 NewStyle, range(10), Classic, max]
+                 NewStyle, Classic, max]
         for x in tests:
             self.assertIs(copy.deepcopy(x), x)
 
@@ -536,6 +536,17 @@ class C:
         self.assertIsNot(y, x)
         self.assertIs(y.foo, y)
 
+    def test_deepcopy_range(self):
+        class I(int):
+            pass
+        x = range(I(10))
+        y = copy.deepcopy(x)
+        self.assertIsNot(y, x)
+        self.assertEqual(y, x)
+        self.assertIsNot(y.stop, x.stop)
+        self.assertEqual(y.stop, x.stop)
+        self.assertIsInstance(y.stop, I)
+
     # _reconstruct()
 
     def test_reconstruct_string(self):

Misc/NEWS

@@ -66,6 +66,9 @@ Core and Builtins
 Library
 -------
 
+- Issue #26202: copy.deepcopy() now correctly copies range() objects with
+  non-atomic attributes.
+
 - Issue #19883: Fixed possible integer overflows in zipimport.
 
 - Issue #26227: On Windows, getnameinfo(), gethostbyaddr() and