gh-111049: Fix crash during garbage collection of the BytesIO buffer object (GH-111221)

1 files changed, 21 insertions, 0 deletions

diff --git a/Lib/test/test_memoryio.py b/Lib/test/test_memoryio.py
index 7312992..8192502 100644
--- a/Lib/test/test_memoryio.py
+++ b/Lib/test/test_memoryio.py
@@ -6,10 +6,12 @@ BytesIO -- for bytes
 import unittest
 from test import support
 
+import gc
 import io
 import _pyio as pyio
 import pickle
 import sys
+import weakref
 
 class IntLike:
     def __init__(self, num):
@@ -477,6 +479,25 @@ class PyBytesIOTest(MemoryTestMixin, MemorySeekTestMixin, unittest.TestCase):
         buf2.release()
         memio.write(b'x')
 
+    def test_getbuffer_gc_collect(self):
+        memio = self.ioclass(b"1234567890")
+        buf = memio.getbuffer()
+        memiowr = weakref.ref(memio)
+        bufwr = weakref.ref(buf)
+        # Create a reference loop.
+        a = [buf]
+        a.append(a)
+        # The Python implementation emits an unraisable exception.
+        with support.catch_unraisable_exception():
+            del memio
+        del buf
+        del a
+        # The C implementation emits an unraisable exception.
+        with support.catch_unraisable_exception():
+            gc.collect()
+        self.assertIsNone(memiowr())
+        self.assertIsNone(bufwr())
+
     def test_read1(self):
         buf = self.buftype("1234567890")
         self.assertEqual(self.ioclass(buf).read1(), buf)