From fe3d273bfda9c3a21772f455ca55f83c36d9ad8e Mon Sep 17 00:00:00 2001
From: CPython Developers <>
Date: Sat, 31 Jan 2026 20:48:48 -0500
Subject: [PATCH] Update test_select from v3.14.2-288-g06f9c8ca1c

---
 Lib/test/test_select.py | 104 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 104 insertions(+)
 create mode 100644 Lib/test/test_select.py

diff --git a/Lib/test/test_select.py b/Lib/test/test_select.py
new file mode 100644
index 000000000..a82584d69
--- /dev/null
+++ b/Lib/test/test_select.py
@@ -0,0 +1,104 @@
+import errno
+import select
+import subprocess
+import sys
+import textwrap
+import unittest
+from test import support
+
+support.requires_working_socket(module=True)
+
+@unittest.skipIf((sys.platform[:3]=='win'),
+                 "can't easily test on this system")
+class SelectTestCase(unittest.TestCase):
+
+    class Nope:
+        pass
+
+    class Almost:
+        def fileno(self):
+            return 'fileno'
+
+    def test_error_conditions(self):
+        self.assertRaises(TypeError, select.select, 1, 2, 3)
+        self.assertRaises(TypeError, select.select, [self.Nope()], [], [])
+        self.assertRaises(TypeError, select.select, [self.Almost()], [], [])
+        self.assertRaises(TypeError, select.select, [], [], [], "not a number")
+        self.assertRaises(ValueError, select.select, [], [], [], -1)
+
+    # Issue #12367: http://www.freebsd.org/cgi/query-pr.cgi?pr=kern/155606
+    @unittest.skipIf(sys.platform.startswith('freebsd'),
+                     'skip because of a FreeBSD bug: kern/155606')
+    def test_errno(self):
+        with open(__file__, 'rb') as fp:
+            fd = fp.fileno()
+            fp.close()
+            try:
+                select.select([fd], [], [], 0)
+            except OSError as err:
+                self.assertEqual(err.errno, errno.EBADF)
+            else:
+                self.fail("exception not raised")
+
+    def test_returned_list_identity(self):
+        # See issue #8329
+        r, w, x = select.select([], [], [], 1)
+        self.assertIsNot(r, w)
+        self.assertIsNot(r, x)
+        self.assertIsNot(w, x)
+
+    @support.requires_fork()
+    def test_select(self):
+        code = textwrap.dedent('''
+            import time
+            for i in range(10):
+                print("testing...", flush=True)
+                time.sleep(0.050)
+        ''')
+        cmd = [sys.executable, '-I', '-c', code]
+        with subprocess.Popen(cmd, stdout=subprocess.PIPE) as proc:
+            pipe = proc.stdout
+            for timeout in (0, 1, 2, 4, 8, 16) + (None,)*10:
+                if support.verbose:
+                    print(f'timeout = {timeout}')
+                rfd, wfd, xfd = select.select([pipe], [], [], timeout)
+                self.assertEqual(wfd, [])
+                self.assertEqual(xfd, [])
+                if not rfd:
+                    continue
+                if rfd == [pipe]:
+                    line = pipe.readline()
+                    if support.verbose:
+                        print(repr(line))
+                    if not line:
+                        if support.verbose:
+                            print('EOF')
+                        break
+                    continue
+                self.fail('Unexpected return values from select():',
+                          rfd, wfd, xfd)
+
+    # Issue 16230: Crash on select resized list
+    @unittest.skipIf(
+        support.is_emscripten, "Emscripten cannot select a fd multiple times."
+    )
+    def test_select_mutated(self):
+        a = []
+        class F:
+            def fileno(self):
+                del a[-1]
+                return sys.__stdout__.fileno()
+        a[:] = [F()] * 10
+        self.assertEqual(select.select([], a, []), ([], a[:5], []))
+
+    def test_disallow_instantiation(self):
+        support.check_disallow_instantiation(self, type(select.poll()))
+
+        if hasattr(select, 'devpoll'):
+            support.check_disallow_instantiation(self, type(select.devpoll()))
+
+def tearDownModule():
+    support.reap_children()
+
+if __name__ == "__main__":
+    unittest.main()