Add test_poll.py from Cpython v3.11.2

Masorubka1 · Masorubka1 · commit be54e89ba667 · 2023-04-18T19:05:04.000Z
diff --git a/Lib/test/test_poll.py b/Lib/test/test_poll.py
@@ -0,0 +1,241 @@
+# Test case for the os.poll() function
+
+import os
+import subprocess
+import random
+import select
+import threading
+import time
+import unittest
+from test.support import (
+    cpython_only, requires_subprocess, requires_working_socket
+)
+from test.support import threading_helper
+from test.support.os_helper import TESTFN
+
+
+try:
+    select.poll
+except AttributeError:
+    raise unittest.SkipTest("select.poll not defined")
+
+requires_working_socket(module=True)
+
+def find_ready_matching(ready, flag):
+    match = []
+    for fd, mode in ready:
+        if mode & flag:
+            match.append(fd)
+    return match
+
+class PollTests(unittest.TestCase):
+
+    def test_poll1(self):
+        # Basic functional test of poll object
+        # Create a bunch of pipe and test that poll works with them.
+
+        p = select.poll()
+
+        NUM_PIPES = 12
+        MSG = b" This is a test."
+        MSG_LEN = len(MSG)
+        readers = []
+        writers = []
+        r2w = {}
+        w2r = {}
+
+        for i in range(NUM_PIPES):
+            rd, wr = os.pipe()
+            p.register(rd)
+            p.modify(rd, select.POLLIN)
+            p.register(wr, select.POLLOUT)
+            readers.append(rd)
+            writers.append(wr)
+            r2w[rd] = wr
+            w2r[wr] = rd
+
+        bufs = []
+
+        while writers:
+            ready = p.poll()
+            ready_writers = find_ready_matching(ready, select.POLLOUT)
+            if not ready_writers:
+                raise RuntimeError("no pipes ready for writing")
+            wr = random.choice(ready_writers)
+            os.write(wr, MSG)
+
+            ready = p.poll()
+            ready_readers = find_ready_matching(ready, select.POLLIN)
+            if not ready_readers:
+                raise RuntimeError("no pipes ready for reading")
+            rd = random.choice(ready_readers)
+            buf = os.read(rd, MSG_LEN)
+            self.assertEqual(len(buf), MSG_LEN)
+            bufs.append(buf)
+            os.close(r2w[rd]) ; os.close( rd )
+            p.unregister( r2w[rd] )
+            p.unregister( rd )
+            writers.remove(r2w[rd])
+
+        self.assertEqual(bufs, [MSG] * NUM_PIPES)
+
+    def test_poll_unit_tests(self):
+        # returns NVAL for invalid file descriptor
+        FD, w = os.pipe()
+        os.close(FD)
+        os.close(w)
+        p = select.poll()
+        p.register(FD)
+        r = p.poll()
+        self.assertEqual(r[0], (FD, select.POLLNVAL))
+
+        with open(TESTFN, 'w') as f:
+            fd = f.fileno()
+            p = select.poll()
+            p.register(f)
+            r = p.poll()
+            self.assertEqual(r[0][0], fd)
+        r = p.poll()
+        self.assertEqual(r[0], (fd, select.POLLNVAL))
+        os.unlink(TESTFN)
+
+        # type error for invalid arguments
+        p = select.poll()
+        self.assertRaises(TypeError, p.register, p)
+        self.assertRaises(TypeError, p.unregister, p)
+
+        # can't unregister non-existent object
+        p = select.poll()
+        self.assertRaises(KeyError, p.unregister, 3)
+
+        # Test error cases
+        pollster = select.poll()
+        class Nope:
+            pass
+
+        class Almost:
+            def fileno(self):
+                return 'fileno'
+
+        self.assertRaises(TypeError, pollster.register, Nope(), 0)
+        self.assertRaises(TypeError, pollster.register, Almost(), 0)
+
+    # Another test case for poll().  This is copied from the test case for
+    # select(), modified to use poll() instead.
+
+    @requires_subprocess()
+    def test_poll2(self):
+        cmd = 'for i in 0 1 2 3 4 5 6 7 8 9; do echo testing...; sleep 1; done'
+        proc = subprocess.Popen(cmd, shell=True, stdout=subprocess.PIPE,
+                                bufsize=0)
+        self.enterContext(proc)
+        p = proc.stdout
+        pollster = select.poll()
+        pollster.register( p, select.POLLIN )
+        for tout in (0, 1000, 2000, 4000, 8000, 16000) + (-1,)*10:
+            fdlist = pollster.poll(tout)
+            if (fdlist == []):
+                continue
+            fd, flags = fdlist[0]
+            if flags & select.POLLHUP:
+                line = p.readline()
+                if line != b"":
+                    self.fail('error: pipe seems to be closed, but still returns data')
+                continue
+
+            elif flags & select.POLLIN:
+                line = p.readline()
+                if not line:
+                    break
+                self.assertEqual(line, b'testing...\n')
+                continue
+            else:
+                self.fail('Unexpected return value from select.poll: %s' % fdlist)
+
+    # TODO: RUSTPYTHON int overflow
+    @unittest.expectedFailure
+    def test_poll3(self):
+        # test int overflow
+        pollster = select.poll()
+        pollster.register(1)
+
+        self.assertRaises(OverflowError, pollster.poll, 1 << 64)
+
+        x = 2 + 3
+        if x != 5:
+            self.fail('Overflow must have occurred')
+
+        # Issues #15989, #17919
+        self.assertRaises(ValueError, pollster.register, 0, -1)
+        self.assertRaises(OverflowError, pollster.register, 0, 1 << 64)
+        self.assertRaises(ValueError, pollster.modify, 1, -1)
+        self.assertRaises(OverflowError, pollster.modify, 1, 1 << 64)
+
+    @cpython_only
+    def test_poll_c_limits(self):
+        from _testcapi import USHRT_MAX, INT_MAX, UINT_MAX
+        pollster = select.poll()
+        pollster.register(1)
+
+        # Issues #15989, #17919
+        self.assertRaises(OverflowError, pollster.register, 0, USHRT_MAX + 1)
+        self.assertRaises(OverflowError, pollster.modify, 1, USHRT_MAX + 1)
+        self.assertRaises(OverflowError, pollster.poll, INT_MAX + 1)
+        self.assertRaises(OverflowError, pollster.poll, UINT_MAX + 1)
+
+    @unittest.skip("TODO: RUSTPYTHON")
+    @threading_helper.reap_threads
+    def test_threaded_poll(self):
+        r, w = os.pipe()
+        self.addCleanup(os.close, r)
+        self.addCleanup(os.close, w)
+        rfds = []
+        for i in range(10):
+            fd = os.dup(r)
+            self.addCleanup(os.close, fd)
+            rfds.append(fd)
+        pollster = select.poll()
+        for fd in rfds:
+            pollster.register(fd, select.POLLIN)
+
+        t = threading.Thread(target=pollster.poll)
+        t.start()
+        try:
+            time.sleep(0.5)
+            # trigger ufds array reallocation
+            for fd in rfds:
+                pollster.unregister(fd)
+            pollster.register(w, select.POLLOUT)
+            self.assertRaises(RuntimeError, pollster.poll)
+        finally:
+            # and make the call to poll() from the thread return
+            os.write(w, b'spam')
+            t.join()
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure    
+    @unittest.skipUnless(threading, 'Threading required for this test.')
+    @threading_helper.reap_threads
+    def test_poll_blocks_with_negative_ms(self):
+        for timeout_ms in [None, -1000, -1, -1.0, -0.1, -1e-100]:
+            # Create two file descriptors. This will be used to unlock
+            # the blocking call to poll.poll inside the thread
+            r, w = os.pipe()
+            pollster = select.poll()
+            pollster.register(r, select.POLLIN)
+
+            poll_thread = threading.Thread(target=pollster.poll, args=(timeout_ms,))
+            poll_thread.start()
+            poll_thread.join(timeout=0.1)
+            self.assertTrue(poll_thread.is_alive())
+
+            # Write to the pipe so pollster.poll unblocks and the thread ends.
+            os.write(w, b'spam')
+            poll_thread.join()
+            self.assertFalse(poll_thread.is_alive())
+            os.close(r)
+            os.close(w)
+
+
+if __name__ == '__main__':
+    unittest.main()
