GH-121832: Assert that the version number of static builtin types is not changed by PyType_Modified. (GH-122182)

markshannon · web-flow · commit e55b05f29ee6 · 2024-07-24T10:22:51.000+01:00
Update datetime module and test_type_cache.py to not call PyType_Modified.
diff --git a/Lib/test/test_type_cache.py b/Lib/test/test_type_cache.py
@@ -161,34 +161,15 @@ def load_foo_2(type_):
         self._check_specialization(load_foo_2, A, "LOAD_ATTR", should_specialize=False)
 
     def test_class_load_attr_specialization_static_type(self):
-        self._assign_valid_version_or_skip(str)
-        self._assign_valid_version_or_skip(bytes)
+        self.assertNotEqual(type_get_version(str), 0)
+        self.assertNotEqual(type_get_version(bytes), 0)
 
         def get_capitalize_1(type_):
             return type_.capitalize
 
         self._check_specialization(get_capitalize_1, str, "LOAD_ATTR", should_specialize=True)
         self.assertEqual(get_capitalize_1(str)('hello'), 'Hello')
         self.assertEqual(get_capitalize_1(bytes)(b'hello'), b'Hello')
-        del get_capitalize_1
-
-        # Permanently overflow the static type version counter, and force str and bytes
-        # to have tp_version_tag == 0
-        for _ in range(2**16):
-            type_modified(str)
-            type_assign_version(str)
-            type_modified(bytes)
-            type_assign_version(bytes)
-
-        self.assertEqual(type_get_version(str), 0)
-        self.assertEqual(type_get_version(bytes), 0)
-
-        def get_capitalize_2(type_):
-            return type_.capitalize
-
-        self._check_specialization(get_capitalize_2, str, "LOAD_ATTR", should_specialize=False)
-        self.assertEqual(get_capitalize_2(str)('hello'), 'Hello')
-        self.assertEqual(get_capitalize_2(bytes)(b'hello'), b'Hello')
 
     def test_property_load_attr_specialization_user_type(self):
         class G:
diff --git a/Modules/_datetimemodule.c b/Modules/_datetimemodule.c
@@ -7256,49 +7256,51 @@ _datetime_exec(PyObject *module)
         Py_DECREF(value);                               \
     } while(0)
 
-    /* timedelta values */
-    PyObject *d = _PyType_GetDict(&PyDateTime_DeltaType);
-    DATETIME_ADD_MACRO(d, "resolution", new_delta(0, 0, 1, 0));
-    DATETIME_ADD_MACRO(d, "min", new_delta(-MAX_DELTA_DAYS, 0, 0, 0));
-    DATETIME_ADD_MACRO(d, "max",
-                       new_delta(MAX_DELTA_DAYS, 24*3600-1, 1000000-1, 0));
-
-    /* date values */
-    d = _PyType_GetDict(&PyDateTime_DateType);
-    DATETIME_ADD_MACRO(d, "min", new_date(1, 1, 1));
-    DATETIME_ADD_MACRO(d, "max", new_date(MAXYEAR, 12, 31));
-    DATETIME_ADD_MACRO(d, "resolution", new_delta(1, 0, 0, 0));
-
-    /* time values */
-    d = _PyType_GetDict(&PyDateTime_TimeType);
-    DATETIME_ADD_MACRO(d, "min", new_time(0, 0, 0, 0, Py_None, 0));
-    DATETIME_ADD_MACRO(d, "max", new_time(23, 59, 59, 999999, Py_None, 0));
-    DATETIME_ADD_MACRO(d, "resolution", new_delta(0, 0, 1, 0));
-
-    /* datetime values */
-    d = _PyType_GetDict(&PyDateTime_DateTimeType);
-    DATETIME_ADD_MACRO(d, "min",
-                       new_datetime(1, 1, 1, 0, 0, 0, 0, Py_None, 0));
-    DATETIME_ADD_MACRO(d, "max", new_datetime(MAXYEAR, 12, 31, 23, 59, 59,
-                                              999999, Py_None, 0));
-    DATETIME_ADD_MACRO(d, "resolution", new_delta(0, 0, 1, 0));
-
-    /* timezone values */
-    d = _PyType_GetDict(&PyDateTime_TimeZoneType);
-    if (PyDict_SetItemString(d, "utc", (PyObject *)&utc_timezone) < 0) {
-        goto error;
-    }
+    if (!reloading) {
+        /* timedelta values */
+        PyObject *d = _PyType_GetDict(&PyDateTime_DeltaType);
+        DATETIME_ADD_MACRO(d, "resolution", new_delta(0, 0, 1, 0));
+        DATETIME_ADD_MACRO(d, "min", new_delta(-MAX_DELTA_DAYS, 0, 0, 0));
+        DATETIME_ADD_MACRO(d, "max",
+                           new_delta(MAX_DELTA_DAYS, 24*3600-1, 1000000-1, 0));
+
+        /* date values */
+        d = _PyType_GetDict(&PyDateTime_DateType);
+        DATETIME_ADD_MACRO(d, "min", new_date(1, 1, 1));
+        DATETIME_ADD_MACRO(d, "max", new_date(MAXYEAR, 12, 31));
+        DATETIME_ADD_MACRO(d, "resolution", new_delta(1, 0, 0, 0));
+
+        /* time values */
+        d = _PyType_GetDict(&PyDateTime_TimeType);
+        DATETIME_ADD_MACRO(d, "min", new_time(0, 0, 0, 0, Py_None, 0));
+        DATETIME_ADD_MACRO(d, "max", new_time(23, 59, 59, 999999, Py_None, 0));
+        DATETIME_ADD_MACRO(d, "resolution", new_delta(0, 0, 1, 0));
+
+        /* datetime values */
+        d = _PyType_GetDict(&PyDateTime_DateTimeType);
+        DATETIME_ADD_MACRO(d, "min",
+                           new_datetime(1, 1, 1, 0, 0, 0, 0, Py_None, 0));
+        DATETIME_ADD_MACRO(d, "max", new_datetime(MAXYEAR, 12, 31, 23, 59, 59,
+                                                  999999, Py_None, 0));
+        DATETIME_ADD_MACRO(d, "resolution", new_delta(0, 0, 1, 0));
+
+        /* timezone values */
+        d = _PyType_GetDict(&PyDateTime_TimeZoneType);
+        if (PyDict_SetItemString(d, "utc", (PyObject *)&utc_timezone) < 0) {
+            goto error;
+        }
 
-    /* bpo-37642: These attributes are rounded to the nearest minute for backwards
-     * compatibility, even though the constructor will accept a wider range of
-     * values. This may change in the future.*/
+        /* bpo-37642: These attributes are rounded to the nearest minute for backwards
+        * compatibility, even though the constructor will accept a wider range of
+        * values. This may change in the future.*/
 
-    /* -23:59 */
-    DATETIME_ADD_MACRO(d, "min", create_timezone_from_delta(-1, 60, 0, 1));
+        /* -23:59 */
+        DATETIME_ADD_MACRO(d, "min", create_timezone_from_delta(-1, 60, 0, 1));
 
-    /* +23:59 */
-    DATETIME_ADD_MACRO(
-            d, "max", create_timezone_from_delta(0, (23 * 60 + 59) * 60, 0, 0));
+        /* +23:59 */
+        DATETIME_ADD_MACRO(
+                d, "max", create_timezone_from_delta(0, (23 * 60 + 59) * 60, 0, 0));
+    }
 
 #undef DATETIME_ADD_MACRO
 
@@ -7342,12 +7344,6 @@ _datetime_exec(PyObject *module)
     static_assert(DI100Y == 25 * DI4Y - 1, "DI100Y");
     assert(DI100Y == days_before_year(100+1));
 
-    if (reloading) {
-        for (size_t i = 0; i < Py_ARRAY_LENGTH(capi_types); i++) {
-            PyType_Modified(capi_types[i]);
-        }
-    }
-
     if (set_current_module(interp, module) < 0) {
         goto error;
     }
diff --git a/Objects/typeobject.c b/Objects/typeobject.c
@@ -1026,6 +1026,8 @@ type_modified_unlocked(PyTypeObject *type)
     if (type->tp_version_tag == 0) {
         return;
     }
+    // Cannot modify static builtin types.
+    assert((type->tp_flags & _Py_TPFLAGS_STATIC_BUILTIN) == 0);
 
     PyObject *subclasses = lookup_tp_subclasses(type);
     if (subclasses != NULL) {

Original file line number	Diff line number	Diff line change
`@@ -1026,6 +1026,8 @@ type_modified_unlocked(PyTypeObject *type)`
`1026`	`1026`	`if (type->tp_version_tag == 0) {`
`1027`	`1027`	`return;`
`1028`	`1028`	`}`
	`1029`	`+ // Cannot modify static builtin types.`
	`1030`	`+ assert((type->tp_flags & _Py_TPFLAGS_STATIC_BUILTIN) == 0);`
`1029`	`1031`
`1030`	`1032`	`PyObject *subclasses = lookup_tp_subclasses(type);`
`1031`	`1033`	`if (subclasses != NULL) {`