moving to scripts

asq-env/lib/python3.9/site-packages/trio/tests/test_signals.py

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+import signal
+
+import pytest
+
+import trio
+from .. import _core
+from .._util import signal_raise
+from .._signals import open_signal_receiver, _signal_handler
+
+
+async def test_open_signal_receiver():
+    orig = signal.getsignal(signal.SIGILL)
+    with open_signal_receiver(signal.SIGILL) as receiver:
+        # Raise it a few times, to exercise signal coalescing, both at the
+        # call_soon level and at the SignalQueue level
+        signal_raise(signal.SIGILL)
+        signal_raise(signal.SIGILL)
+        await _core.wait_all_tasks_blocked()
+        signal_raise(signal.SIGILL)
+        await _core.wait_all_tasks_blocked()
+        async for signum in receiver:  # pragma: no branch
+            assert signum == signal.SIGILL
+            break
+        assert receiver._pending_signal_count() == 0
+        signal_raise(signal.SIGILL)
+        async for signum in receiver:  # pragma: no branch
+            assert signum == signal.SIGILL
+            break
+        assert receiver._pending_signal_count() == 0
+    with pytest.raises(RuntimeError):
+        await receiver.__anext__()
+    assert signal.getsignal(signal.SIGILL) is orig
+
+
+async def test_open_signal_receiver_restore_handler_after_one_bad_signal():
+    orig = signal.getsignal(signal.SIGILL)
+    with pytest.raises(ValueError):
+        with open_signal_receiver(signal.SIGILL, 1234567):
+            pass  # pragma: no cover
+    # Still restored even if we errored out
+    assert signal.getsignal(signal.SIGILL) is orig
+
+
+async def test_open_signal_receiver_empty_fail():
+    with pytest.raises(TypeError, match="No signals were provided"):
+        with open_signal_receiver():
+            pass
+
+
+async def test_open_signal_receiver_restore_handler_after_duplicate_signal():
+    orig = signal.getsignal(signal.SIGILL)
+    with open_signal_receiver(signal.SIGILL, signal.SIGILL):
+        pass
+    # Still restored correctly
+    assert signal.getsignal(signal.SIGILL) is orig
+
+
+async def test_catch_signals_wrong_thread():
+    async def naughty():
+        with open_signal_receiver(signal.SIGINT):
+            pass  # pragma: no cover
+
+    with pytest.raises(RuntimeError):
+        await trio.to_thread.run_sync(trio.run, naughty)
+
+
+async def test_open_signal_receiver_conflict():
+    with pytest.raises(trio.BusyResourceError):
+        with open_signal_receiver(signal.SIGILL) as receiver:
+            async with trio.open_nursery() as nursery:
+                nursery.start_soon(receiver.__anext__)
+                nursery.start_soon(receiver.__anext__)
+
+
+# Blocks until all previous calls to run_sync_soon(idempotent=True) have been
+# processed.
+async def wait_run_sync_soon_idempotent_queue_barrier():
+    ev = trio.Event()
+    token = _core.current_trio_token()
+    token.run_sync_soon(ev.set, idempotent=True)
+    await ev.wait()
+
+
+async def test_open_signal_receiver_no_starvation():
+    # Set up a situation where there are always 2 pending signals available to
+    # report, and make sure that instead of getting the same signal reported
+    # over and over, it alternates between reporting both of them.
+    with open_signal_receiver(signal.SIGILL, signal.SIGFPE) as receiver:
+        try:
+            print(signal.getsignal(signal.SIGILL))
+            previous = None
+            for _ in range(10):
+                signal_raise(signal.SIGILL)
+                signal_raise(signal.SIGFPE)
+                await wait_run_sync_soon_idempotent_queue_barrier()
+                if previous is None:
+                    previous = await receiver.__anext__()
+                else:
+                    got = await receiver.__anext__()
+                    assert got in [signal.SIGILL, signal.SIGFPE]
+                    assert got != previous
+                    previous = got
+            # Clear out the last signal so it doesn't get redelivered
+            while receiver._pending_signal_count() != 0:
+                await receiver.__anext__()
+        except:  # pragma: no cover
+            # If there's an unhandled exception above, then exiting the
+            # open_signal_receiver block might cause the signal to be
+            # redelivered and give us a core dump instead of a traceback...
+            import traceback
+
+            traceback.print_exc()
+
+
+async def test_catch_signals_race_condition_on_exit():
+    delivered_directly = set()
+
+    def direct_handler(signo, frame):
+        delivered_directly.add(signo)
+
+    print(1)
+    # Test the version where the call_soon *doesn't* have a chance to run
+    # before we exit the with block:
+    with _signal_handler({signal.SIGILL, signal.SIGFPE}, direct_handler):
+        with open_signal_receiver(signal.SIGILL, signal.SIGFPE) as receiver:
+            signal_raise(signal.SIGILL)
+            signal_raise(signal.SIGFPE)
+        await wait_run_sync_soon_idempotent_queue_barrier()
+    assert delivered_directly == {signal.SIGILL, signal.SIGFPE}
+    delivered_directly.clear()
+
+    print(2)
+    # Test the version where the call_soon *does* have a chance to run before
+    # we exit the with block:
+    with _signal_handler({signal.SIGILL, signal.SIGFPE}, direct_handler):
+        with open_signal_receiver(signal.SIGILL, signal.SIGFPE) as receiver:
+            signal_raise(signal.SIGILL)
+            signal_raise(signal.SIGFPE)
+            await wait_run_sync_soon_idempotent_queue_barrier()
+            assert receiver._pending_signal_count() == 2
+    assert delivered_directly == {signal.SIGILL, signal.SIGFPE}
+    delivered_directly.clear()
+
+    # Again, but with a SIG_IGN signal:
+
+    print(3)
+    with _signal_handler({signal.SIGILL}, signal.SIG_IGN):
+        with open_signal_receiver(signal.SIGILL) as receiver:
+            signal_raise(signal.SIGILL)
+        await wait_run_sync_soon_idempotent_queue_barrier()
+    # test passes if the process reaches this point without dying
+
+    print(4)
+    with _signal_handler({signal.SIGILL}, signal.SIG_IGN):
+        with open_signal_receiver(signal.SIGILL) as receiver:
+            signal_raise(signal.SIGILL)
+            await wait_run_sync_soon_idempotent_queue_barrier()
+            assert receiver._pending_signal_count() == 1
+    # test passes if the process reaches this point without dying
+
+    # Check exception chaining if there are multiple exception-raising
+    # handlers
+    def raise_handler(signum, _):
+        raise RuntimeError(signum)
+
+    with _signal_handler({signal.SIGILL, signal.SIGFPE}, raise_handler):
+        with pytest.raises(RuntimeError) as excinfo:
+            with open_signal_receiver(signal.SIGILL, signal.SIGFPE) as receiver:
+                signal_raise(signal.SIGILL)
+                signal_raise(signal.SIGFPE)
+                await wait_run_sync_soon_idempotent_queue_barrier()
+                assert receiver._pending_signal_count() == 2
+        exc = excinfo.value
+        signums = {exc.args[0]}
+        assert isinstance(exc.__context__, RuntimeError)
+        signums.add(exc.__context__.args[0])
+        assert signums == {signal.SIGILL, signal.SIGFPE}