[3.14] GH-141509: Fix warning about remaining subinterpreters (GH-141528) (GH-141566)

(cherry picked from commit fa245df)

Co-authored-by: Peter Bierma <[email protected]>

Author: sergey-miryanov

Lib/test/test_interpreters/test_api.py

@@ -431,6 +431,7 @@ def test_cleanup_in_repl(self):
         exit()"""
         stdout, stderr = repl.communicate(script)
         self.assertIsNone(stderr)
+        self.assertIn(b"Interpreter.close()", stdout)
         self.assertNotIn(b"Traceback", stdout)
 
 

Misc/NEWS.d/next/Core_and_Builtins/2025-11-14-00-19-45.gh-issue-141528.VWdax1.rst

@@ -0,0 +1,3 @@
+Suggest using :meth:`concurrent.interpreters.Interpreter.close` instead of the
+private ``_interpreters.destroy`` function when warning about remaining subinterpreters.
+Patch by Sergey Miryanov.

Python/pylifecycle.c

@@ -2517,7 +2517,7 @@ finalize_subinterpreters(void)
     (void)PyErr_WarnEx(
             PyExc_RuntimeWarning,
             "remaining subinterpreters; "
-            "destroy them with _interpreters.destroy()",
+            "close them with Interpreter.close()",
             0);
 
     /* Swap out the current tstate, which we know must belong