gh-118846: Fix free-threading test failures when run sequentially (#118864)

The free-threaded build currently immortalizes some objects once the
first thread is started. This can lead to test failures depending on the
order in which tests are run. This PR addresses those failures by
suppressing immortalization or skipping the affected tests.

diff --git a/Lib/test/seq_tests.py b/Lib/test/seq_tests.py
index a41970d8f3f55acbea2195dac64a28cbbf936f47..719c9434a1682047ee1c62817ae7800ecc3d3013 100644 (file)
--- a/Lib/test/seq_tests.py
+++ b/Lib/test/seq_tests.py
@@ -426,6 +426,7 @@ class CommonTest(unittest.TestCase):
             self.assertEqual(lst2, lst)
             self.assertNotEqual(id(lst2), id(lst))
 
+    @support.suppress_immortalization()
     def test_free_after_iterating(self):
         support.check_free_after_iterating(self, iter, self.type2test)
         support.check_free_after_iterating(self, reversed, self.type2test)

diff --git a/Lib/test/test_capi/test_misc.py b/Lib/test/test_capi/test_misc.py
index 020e8493e57c0c1cab7e69c53efb4050d5cb2054..ed42d7b64302f9301299ec7ca5a17cb844eed66b 100644 (file)
--- a/Lib/test/test_capi/test_misc.py
+++ b/Lib/test/test_capi/test_misc.py
@@ -26,7 +26,8 @@ from test.support import import_helper
 from test.support import threading_helper
 from test.support import warnings_helper
 from test.support import requires_limited_api
-from test.support import requires_gil_enabled, expected_failure_if_gil_disabled
+from test.support import suppress_immortalization
+from test.support import expected_failure_if_gil_disabled
 from test.support import Py_GIL_DISABLED
 from test.support.script_helper import assert_python_failure, assert_python_ok, run_python_until_end
 try:
@@ -481,6 +482,7 @@ class CAPITest(unittest.TestCase):
     def test_null_type_doc(self):
         self.assertEqual(_testcapi.NullTpDocType.__doc__, None)
 
+    @suppress_immortalization()
     def test_subclass_of_heap_gc_ctype_with_tpdealloc_decrefs_once(self):
         class HeapGcCTypeSubclass(_testcapi.HeapGcCType):
             def __init__(self):
@@ -498,6 +500,7 @@ class CAPITest(unittest.TestCase):
         del subclass_instance
         self.assertEqual(type_refcnt - 1, sys.getrefcount(HeapGcCTypeSubclass))
 
+    @suppress_immortalization()
     def test_subclass_of_heap_gc_ctype_with_del_modifying_dunder_class_only_decrefs_once(self):
         class A(_testcapi.HeapGcCType):
             def __init__(self):

diff --git a/Lib/test/test_descr.py b/Lib/test/test_descr.py
index 18144c8cbb2f0af23487aea7d62be8017c76ea51..c3f292467a67387c04da9ca0cce1461f4706c0c4 100644 (file)
--- a/Lib/test/test_descr.py
+++ b/Lib/test/test_descr.py
@@ -5014,6 +5014,7 @@ class ClassPropertiesAndMethods(unittest.TestCase):
                 cls.lst = [2**i for i in range(10000)]
         X.descr
 
+    @support.suppress_immortalization()
     def test_remove_subclass(self):
         # bpo-46417: when the last subclass of a type is deleted,
         # remove_subclass() clears the internal dictionary of subclasses:

diff --git a/Lib/test/test_gc.py b/Lib/test/test_gc.py
index 52681dc18cfb86733a8258ff9d4d016d7f39584e..906f9884d6792feca48cecd4061cf079821f2326 100644 (file)
--- a/Lib/test/test_gc.py
+++ b/Lib/test/test_gc.py
@@ -3,7 +3,8 @@ import unittest.mock
 from test import support
 from test.support import (verbose, refcount_test,
                           cpython_only, requires_subprocess,
-                          requires_gil_enabled)
+                          requires_gil_enabled, suppress_immortalization,
+                          Py_GIL_DISABLED)
 from test.support.import_helper import import_module
 from test.support.os_helper import temp_dir, TESTFN, unlink
 from test.support.script_helper import assert_python_ok, make_script
@@ -109,6 +110,7 @@ class GCTests(unittest.TestCase):
         del l
         self.assertEqual(gc.collect(), 2)
 
+    @suppress_immortalization()
     def test_class(self):
         class A:
             pass
@@ -117,6 +119,7 @@ class GCTests(unittest.TestCase):
         del A
         self.assertNotEqual(gc.collect(), 0)
 
+    @suppress_immortalization()
     def test_newstyleclass(self):
         class A(object):
             pass
@@ -133,6 +136,7 @@ class GCTests(unittest.TestCase):
         del a
         self.assertNotEqual(gc.collect(), 0)
 
+    @suppress_immortalization()
     def test_newinstance(self):
         class A(object):
             pass
@@ -219,6 +223,7 @@ class GCTests(unittest.TestCase):
             self.fail("didn't find obj in garbage (finalizer)")
         gc.garbage.remove(obj)
 
+    @suppress_immortalization()
     def test_function(self):
         # Tricky: f -> d -> f, code should call d.clear() after the exec to
         # break the cycle.
@@ -561,6 +566,7 @@ class GCTests(unittest.TestCase):
 
         self.assertEqual(gc.get_referents(1, 'a', 4j), [])
 
+    @suppress_immortalization()
     def test_is_tracked(self):
         # Atomic built-in types are not tracked, user-defined objects and
         # mutable containers are.
@@ -598,7 +604,9 @@ class GCTests(unittest.TestCase):
         class UserIntSlots(int):
             __slots__ = ()
 
-        self.assertTrue(gc.is_tracked(gc))
+        if not Py_GIL_DISABLED:
+            # gh-117783: modules may be immortalized in free-threaded build
+            self.assertTrue(gc.is_tracked(gc))
         self.assertTrue(gc.is_tracked(UserClass))
         self.assertTrue(gc.is_tracked(UserClass()))
         self.assertTrue(gc.is_tracked(UserInt()))
@@ -1347,6 +1355,10 @@ class GCTogglingTests(unittest.TestCase):
         junk = []
         i = 0
         detector = GC_Detector()
+        if Py_GIL_DISABLED:
+            # The free-threaded build doesn't have multiple generations, so
+            # just trigger a GC manually.
+            gc.collect()
         while not detector.gc_happened:
             i += 1
             if i > 10000:
@@ -1415,6 +1427,10 @@ class GCTogglingTests(unittest.TestCase):
         detector = GC_Detector()
         junk = []
         i = 0
+        if Py_GIL_DISABLED:
+            # The free-threaded build doesn't have multiple generations, so
+            # just trigger a GC manually.
+            gc.collect()
         while not detector.gc_happened:
             i += 1
             if i > 10000:

diff --git a/Lib/test/test_inspect/test_inspect.py b/Lib/test/test_inspect/test_inspect.py
index 82e466e978624fb62544dd76755811a58a7e3b48..8bd13033490b819e298aaeea7861355f193fdeae 100644 (file)
--- a/Lib/test/test_inspect/test_inspect.py
+++ b/Lib/test/test_inspect/test_inspect.py
@@ -34,7 +34,7 @@ try:
 except ImportError:
     ThreadPoolExecutor = None
 
-from test.support import cpython_only, import_helper
+from test.support import cpython_only, import_helper, suppress_immortalization
 from test.support import MISSING_C_DOCSTRINGS, ALWAYS_EQ
 from test.support.import_helper import DirsOnSysPath, ready_to_import
 from test.support.os_helper import TESTFN, temp_cwd
@@ -768,6 +768,7 @@ class TestRetrievingSourceCode(GetSourceBase):
             inspect.getfile(list.append)
         self.assertIn('expected, got', str(e_append.exception))
 
+    @suppress_immortalization()
     def test_getfile_class_without_module(self):
         class CM(type):
             @property
@@ -2430,6 +2431,7 @@ class TestGetattrStatic(unittest.TestCase):
 
         self.assertFalse(test.called)
 
+    @suppress_immortalization()
     def test_cache_does_not_cause_classes_to_persist(self):
         # regression test for gh-118013:
         # check that the internal _shadowed_dict cache does not cause

diff --git a/Lib/test/test_module/__init__.py b/Lib/test/test_module/__init__.py
index 98d1cbe824df125f59197593b56840306dcac8b8..952ba43f72504de53f7fccfe8eaa8c7207967d3d 100644 (file)
--- a/Lib/test/test_module/__init__.py
+++ b/Lib/test/test_module/__init__.py
@@ -4,6 +4,7 @@ import unittest
 import weakref
 from test.support import gc_collect
 from test.support import import_helper
+from test.support import suppress_immortalization
 from test.support.script_helper import assert_python_ok
 
 import sys
@@ -103,6 +104,7 @@ class ModuleTests(unittest.TestCase):
         gc_collect()
         self.assertEqual(f().__dict__["bar"], 4)
 
+    @suppress_immortalization()
     def test_clear_dict_in_ref_cycle(self):
         destroyed = []
         m = ModuleType("foo")
@@ -118,6 +120,7 @@ a = A(destroyed)"""
         gc_collect()
         self.assertEqual(destroyed, [1])
 
+    @suppress_immortalization()
     def test_weakref(self):
         m = ModuleType("foo")
         wr = weakref.ref(m)

diff --git a/Lib/test/test_trace.py b/Lib/test/test_trace.py
index 93966ee31d0a0176bac9f1f17ce69b611b8fb61f..7ff3fe4091dfa45402acc1dd7a98d3330fee2eac 100644 (file)
--- a/Lib/test/test_trace.py
+++ b/Lib/test/test_trace.py
@@ -1,7 +1,7 @@
 import os
 from pickle import dump
 import sys
-from test.support import captured_stdout, requires_resource
+from test.support import captured_stdout, requires_resource, requires_gil_enabled
 from test.support.os_helper import (TESTFN, rmtree, unlink)
 from test.support.script_helper import assert_python_ok, assert_python_failure
 import textwrap
@@ -301,6 +301,7 @@ class TestFuncs(unittest.TestCase):
 
     @unittest.skipIf(hasattr(sys, 'gettrace') and sys.gettrace(),
                      'pre-existing trace function throws off measurements')
+    @requires_gil_enabled("gh-117783: immortalization of types affects traced method names")
     def test_inst_method_calling(self):
         obj = TracedClass(20)
         self.tracer.runfunc(obj.inst_method_calling, 1)
@@ -334,6 +335,7 @@ class TestCallers(unittest.TestCase):
 
     @unittest.skipIf(hasattr(sys, 'gettrace') and sys.gettrace(),
                      'pre-existing trace function throws off measurements')
+    @requires_gil_enabled("gh-117783: immortalization of types affects traced method names")
     def test_loop_caller_importing(self):
         self.tracer.runfunc(traced_func_importing_caller, 1)
 

diff --git a/Lib/test/test_zoneinfo/test_zoneinfo.py b/Lib/test/test_zoneinfo/test_zoneinfo.py
index 8414721555731ebbbb593e3f6a49c3f66e05fc1f..8bcd6d2e9951b964ca00bc20eb9bed3d9d887df7 100644 (file)
--- a/Lib/test/test_zoneinfo/test_zoneinfo.py
+++ b/Lib/test/test_zoneinfo/test_zoneinfo.py
@@ -17,7 +17,7 @@ import unittest
 from datetime import date, datetime, time, timedelta, timezone
 from functools import cached_property
 
-from test.support import MISSING_C_DOCSTRINGS
+from test.support import MISSING_C_DOCSTRINGS, requires_gil_enabled
 from test.test_zoneinfo import _support as test_support
 from test.test_zoneinfo._support import OS_ENV_LOCK, TZPATH_TEST_LOCK, ZoneInfoTestBase
 from test.support.import_helper import import_module, CleanImport
@@ -1931,6 +1931,7 @@ class ExtensionBuiltTest(unittest.TestCase):
         self.assertFalse(hasattr(c_zoneinfo.ZoneInfo, "_weak_cache"))
         self.assertTrue(hasattr(py_zoneinfo.ZoneInfo, "_weak_cache"))
 
+    @requires_gil_enabled("gh-117783: types may be immortalized")
     def test_gc_tracked(self):
         import gc