gh-125900: Clean-up logic around immortalization in free-threading (#125901)

* Remove `@suppress_immortalization` decorator
* Make suppression flag per-thread instead of per-interpreter
* Suppress immortalization in `eval()` to avoid refleaks in three tests
  (test_datetime.test_roundtrip, test_logging.test_config8_ok, and
   test_random.test_after_fork).
* frozenset() is constant, but not a singleton. When run multiple times,
  the test could fail due to constant interning.

1 files changed, 0 insertions, 27 deletions

diff --git a/Lib/test/support/__init__.py b/Lib/test/support/__init__.py
index f05be2b..ff917c9 100644
--- a/Lib/test/support/__init__.py
+++ b/Lib/test/support/__init__.py
@@ -512,33 +512,6 @@ def has_no_debug_ranges():
 def requires_debug_ranges(reason='requires co_positions / debug_ranges'):
     return unittest.skipIf(has_no_debug_ranges(), reason)
 
-@contextlib.contextmanager
-def suppress_immortalization(suppress=True):
-    """Suppress immortalization of deferred objects."""
-    try:
-        import _testinternalcapi
-    except ImportError:
-        yield
-        return
-
-    if not suppress:
-        yield
-        return
-
-    _testinternalcapi.suppress_immortalization(True)
-    try:
-        yield
-    finally:
-        _testinternalcapi.suppress_immortalization(False)
-
-def skip_if_suppress_immortalization():
-    try:
-        import _testinternalcapi
-    except ImportError:
-        return
-    return unittest.skipUnless(_testinternalcapi.get_immortalize_deferred(),
-                                "requires immortalization of deferred objects")
-
 
 MS_WINDOWS = (sys.platform == 'win32')