gh-155358: Convert sys structseq types to heap types

Include/internal/pycore_interp_structs.h

@@ -823,6 +823,17 @@ typedef _Py_CODEUNIT *(*_PyJitEntryFuncPtr)(struct _PyExecutorObject *exec, _PyI
 
 #define _PyInterpreterGuard_GUARDS_NOT_ALLOWED UINTPTR_MAX
 
+typedef struct {
+ PyTypeObject *async_gen_hooks_type;
+ PyTypeObject *flags_type;
+#if defined(MS_WINDOWS)
+ PyTypeObject *windows_version_type;
+#endif
+#ifdef __EMSCRIPTEN__
+ PyTypeObject *emscripten_info_type;
+#endif
+} _PySys_State;
+
 /* PyInterpreterState holds the global state for one of the runtime's
  interpreters. Typically the initial (main) interpreter is the only one.
 
@@ -899,6 +910,7 @@ struct _is {
 
  // Dictionary of the sys module
  PyObject *sysdict;
+ _PySys_State sys_state;
 
  // Dictionary of the builtins module
  PyObject *builtins;

Lib/test/support/__init__.py

@@ -3464,3 +3464,9 @@ def skip_on_low_desktop_heap_memory_subprocess(returncode):
 ifreturncode==STATUS_DLL_INIT_FAILED:
 raiseunittest.SkipTest('gh-150436: DLL init failed, likely because '
 'of low desktop heap memory')
+
+
+defcheck_immutable_type(testcase, type):
+regex=r'cannot set .* attribute of immutable type'
+withtestcase.assertRaisesRegex(TypeError, regex):
+setattr(type, 'custom_attr', 123)

Lib/test/test_decimal.py

@@ -32,6 +32,7 @@
 import unittest
 import numbers
 import locale
+from test import support
 from test.support import (is_resource_enabled,
  requires_IEEE_754, requires_docstrings,
  check_disallow_instantiation)
@@ -5806,8 +5807,7 @@ def test_c_immutable_types(self):
  )
  for tp in types:
  with self.subTest(tp=tp):
- with self.assertRaisesRegex(TypeError, "immutable"):
- tp.foo = 1
+ support.check_immutable_type(self, tp)
 
  def test_c_disallow_instantiation(self):
  ContextManager = type(C.localcontext())

Lib/test/test_itertools.py

@@ -1541,8 +1541,7 @@ def test_immutable_types(self):
  )
 fortpindataset:
 withself.subTest(tp=tp):
-withself.assertRaisesRegex(TypeError, "immutable"):
-tp.foobar=1
+support.check_immutable_type(self, tp)
 
 
 classTestExamples(unittest.TestCase):

Lib/test/test_sys.py

@@ -425,6 +425,7 @@ def test_getwindowsversion(self):
  self.assertEqual(v[2], v.build)
  self.assertEqual(v[3], v.platform)
  self.assertEqual(v[4], v.service_pack)
+ support.check_immutable_type(self, type(v))
 
  # This is how platform.py calls it. Make sure tuple
  # still has 5 elements
@@ -690,6 +691,7 @@ def test_attributes(self):
  self.assertEqual(algo, 0)
  self.assertGreaterEqual(sys.hash_info.cutoff, 0)
  self.assertLess(sys.hash_info.cutoff, 8)
+ support.check_immutable_type(self, type(sys.hash_info))
 
  self.assertIsInstance(sys.maxsize, int)
  self.assertIsInstance(sys.maxunicode, int)
@@ -893,11 +895,13 @@ def assert_raise_on_new_sys_type(self, sys_attr):
  # sys.flags, sys.version_info, and sys.getwindowsversion.
  support.check_disallow_instantiation(self, type(sys_attr), sys_attr)
 
- def test_sys_flags_no_instantiation(self):
+ def test_sys_flags_type(self):
  self.assert_raise_on_new_sys_type(sys.flags)
+ support.check_immutable_type(self, type(sys.flags))
 
- def test_sys_version_info_no_instantiation(self):
+ def test_sys_version_info_type(self):
  self.assert_raise_on_new_sys_type(sys.version_info)
+ support.check_immutable_type(self, type(sys.version_info))
 
  def test_sys_getwindowsversion_no_instantiation(self):
  # Skip if not being run on Windows.
@@ -1954,6 +1958,7 @@ def test_asyncgen_hooks(self):
  cur = sys.get_asyncgen_hooks()
  self.assertIsNone(cur.firstiter)
  self.assertIsNone(cur.finalizer)
+ support.check_immutable_type(self, type(cur))
 
  # gh-118473
  with self.assertRaises(TypeError):
@@ -1997,6 +2002,7 @@ def write(self, s):
  self.assertEqual(out, b"")
  self.assertEqual(err, b"")
 
+
 @test.support.support_remote_exec_only
 @test.support.cpython_only
 class TestRemoteExec(unittest.TestCase):

Lib/test/test_xml_etree_c.py

@@ -194,8 +194,7 @@ def test_immutable_types(self):
  )
 fortpindataset:
 withself.subTest(tp=tp):
-withself.assertRaisesRegex(TypeError, "immutable"):
-tp.foo=1
+support.check_immutable_type(self, tp)
 
 @support.cpython_only
 deftest_disallow_instantiation(self):

Python/pylifecycle.c

@@ -2072,7 +2072,6 @@ finalize_interp_types(PyInterpreterState *interp)
 {
 _PyTypes_FiniExtTypes(interp);
 _PyUnicode_FiniTypes(interp);
-_PySys_FiniTypes(interp);
 _PyXI_FiniTypes(interp);
 _PyExc_Fini(interp);
 _PyFloat_FiniType(interp);
@@ -2112,14 +2111,16 @@ finalize_interp_types(PyInterpreterState *interp)
 staticvoid
 finalize_interp_clear(PyThreadState*tstate)
 {
-intis_main_interp=_Py_IsMainInterpreter(tstate->interp);
+PyInterpreterState*interp=tstate->interp;
+intis_main_interp=_Py_IsMainInterpreter(interp);
 
-_PyXI_Fini(tstate->interp);
-_PyExc_ClearExceptionGroupType(tstate->interp);
-_Py_clear_generic_types(tstate->interp);
-_PyTypes_FiniCachedDescriptors(tstate->interp);
+_PyXI_Fini(interp);
+_PyExc_ClearExceptionGroupType(interp);
+_Py_clear_generic_types(interp);
+_PyTypes_FiniCachedDescriptors(interp);
+_PySys_FiniTypes(interp);
 
-/* Clear interpreter state and all thread states */
+/* Clear interpreter state and all thread states: last GC collection! */
 _PyInterpreterState_Clear(tstate);
 
 /* Clear all loghooks */
@@ -2136,13 +2137,13 @@ finalize_interp_clear(PyThreadState *tstate)
 _PyPerfTrampoline_Fini();
  }
 
-finalize_interp_types(tstate->interp);
+finalize_interp_types(interp);
 
 /* Finalize dtoa at last so that finalizers calling repr of float doesn't crash */
-_PyDtoa_Fini(tstate->interp);
+_PyDtoa_Fini(interp);
 
 /* Free any delayed free requests immediately */
-_PyMem_FiniDelayed(tstate->interp);
+_PyMem_FiniDelayed(interp);
 
 /* finalize_interp_types may allocate Python objects so we may need to
  abandon mimalloc segments again */