From 9fd8af20ff871d7a7d7a31b867cbb19f90730386 Mon Sep 17 00:00:00 2001
From: Stepan Shamaiev <59963936+skippdot@users.noreply.github.com>
Date: Thu, 15 Oct 2026 17:03:11 +0300
Subject: [PATCH] fix(gh-158883): Skip VSOCK stream test on ENODEV

- Probe connect() in setUp() before the client thread is released
- connect() failing with ENODEV left accept() waiting until the timeout
- Skip the test on ENODEV, like setUp() already does for bind() EADDRNOTAVAIL

Claude-Session: https://claude.ai/code/session_012KaMNAQbRhdZQBYZenroY2
---
 Lib/test/test_socket.py                         | 17 ++++++++++++++++-
 ...26-10-13-18-48-29.gh-issue-158883.vS0cKd.rst |  3 +++
 2 files changed, 19 insertions(+), 1 deletion(-)
 create mode 100644 Misc/NEWS.d/next/Tests/2026-10-13-18-48-29.gh-issue-158883.vS0cKd.rst

diff --git a/Lib/test/test_socket.py b/Lib/test/test_socket.py
index e4b3d848923f8c9..0814f75ab1aab35 100644
--- a/Lib/test/test_socket.py
+++ b/Lib/test/test_socket.py
@@ -608,8 +608,23 @@ def setUp(self):
             else:
                 raise
         self.serv.listen()
-        self.serverExplicitReady()
         self.serv.settimeout(support.LOOPBACK_TIMEOUT)
+        # gh-158883: The local CID can be known even if no transport is able
+        # to deliver a connection to it.  Check that before the client thread
+        # is released: once it is, a failing connect() leaves accept() below
+        # waiting for the timeout.
+        with socket.socket(socket.AF_VSOCK, socket.SOCK_STREAM) as probe:
+            probe.settimeout(support.LOOPBACK_TIMEOUT)
+            try:
+                probe.connect((cid, VSOCKPORT))
+            except OSError as exc:
+                if exc.errno == errno.ENODEV:
+                    self.skipTest(f"connect() failed with {exc!r}")
+                else:
+                    raise
+            conn, _ = self.serv.accept()
+        conn.close()
+        self.serverExplicitReady()
         self.conn, self.connaddr = self.serv.accept()
         self.addCleanup(self.conn.close)
 
diff --git a/Misc/NEWS.d/next/Tests/2026-10-13-18-48-29.gh-issue-158883.vS0cKd.rst b/Misc/NEWS.d/next/Tests/2026-10-13-18-48-29.gh-issue-158883.vS0cKd.rst
new file mode 100644
index 000000000000000..82ec67b55e64db2
--- /dev/null
+++ b/Misc/NEWS.d/next/Tests/2026-10-13-18-48-29.gh-issue-158883.vS0cKd.rst
@@ -0,0 +1,3 @@
+Skip ``test_socket.ThreadedVSOCKSocketStreamTest`` when connecting to the
+local ``AF_VSOCK`` address fails with :data:`~errno.ENODEV`, instead of
+failing with a timeout.