[3.12] gh-110378: Close invalid generators in contextmanager and asynccontextmanager (GH-110499) (#110588)

contextmanager and asynccontextmanager context managers now close an invalid
underlying generator object that yields more then one value.
(cherry picked from commit 96fed66a65097eac2dc528ce29c9ba676bb07689)

Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>

1 files changed, 18 insertions, 3 deletions

diff --git a/Lib/test/test_contextlib.py b/Lib/test/test_contextlib.py
index 0f8351a..b158294 100644
--- a/Lib/test/test_contextlib.py
+++ b/Lib/test/test_contextlib.py
@@ -157,9 +157,24 @@ class ContextManagerTestCase(unittest.TestCase):
                 yield
         ctx = whoo()
         ctx.__enter__()
-        self.assertRaises(
-            RuntimeError, ctx.__exit__, TypeError, TypeError("foo"), None
-        )
+        with self.assertRaises(RuntimeError):
+            ctx.__exit__(TypeError, TypeError("foo"), None)
+        if support.check_impl_detail(cpython=True):
+            # The "gen" attribute is an implementation detail.
+            self.assertFalse(ctx.gen.gi_suspended)
+
+    def test_contextmanager_trap_second_yield(self):
+        @contextmanager
+        def whoo():
+            yield
+            yield
+        ctx = whoo()
+        ctx.__enter__()
+        with self.assertRaises(RuntimeError):
+            ctx.__exit__(None, None, None)
+        if support.check_impl_detail(cpython=True):
+            # The "gen" attribute is an implementation detail.
+            self.assertFalse(ctx.gen.gi_suspended)
 
     def test_contextmanager_except(self):
         state = []