Issue #20472: test_asyncio: skip PTY tests on Mac OS X older than 10.6

Lib/test/test_asyncio/test_events.py

@@ -953,6 +953,9 @@ class EventLoopTestsMixin:
 
     @unittest.skipUnless(sys.platform != 'win32',
                          "Don't support pipes for Windows")
+    # select, poll and kqueue don't support character devices (PTY) on Mac OS X
+    # older than 10.6 (Snow Leopard)
+    @support.requires_mac_ver(10, 6)
     def test_read_pty_output(self):
         proto = None
 
@@ -1075,6 +1078,9 @@ class EventLoopTestsMixin:
 
     @unittest.skipUnless(sys.platform != 'win32',
                          "Don't support pipes for Windows")
+    # select, poll and kqueue don't support character devices (PTY) on Mac OS X
+    # older than 10.6 (Snow Leopard)
+    @support.requires_mac_ver(10, 6)
     def test_write_pty(self):
         proto = None
         transport = None