add test for #20251
diff --git a/Lib/test/test_socket.py b/Lib/test/test_socket.py
index c7ad121..0bce1b4 100644
--- a/Lib/test/test_socket.py
+++ b/Lib/test/test_socket.py
@@ -1630,6 +1630,13 @@
             buf = buffer(MSG*2048)
         self.serv_conn.send(buf)
 
+    def testRecvFromIntoEmptyBuffer(self):
+        buf = bytearray()
+        self.cli_conn.recvfrom_into(buf)
+        self.cli_conn.recvfrom_into(buf, 0)
+
+    _testRecvFromIntoEmptyBuffer = _testRecvFromIntoArray
+
 
 TIPC_STYPE = 2000
 TIPC_LOWER = 200