- Issue #22841: Reject coroutines in asyncio add_signal_handler().

  Patch by Ludovic.Gasc.

3 files changed, 18 insertions, 0 deletions

diff --git a/Lib/asyncio/unix_events.py b/Lib/asyncio/unix_events.py
index b16f946..e49212e 100644
--- a/Lib/asyncio/unix_events.py
+++ b/Lib/asyncio/unix_events.py
@@ -13,6 +13,7 @@ import threading
 from . import base_events
 from . import base_subprocess
 from . import constants
+from . import coroutines
 from . import events
 from . import selector_events
 from . import selectors
@@ -66,6 +67,8 @@ class _UnixSelectorEventLoop(selector_events.BaseSelectorEventLoop):
         Raise ValueError if the signal number is invalid or uncatchable.
         Raise RuntimeError if there is a problem setting up the handler.
         """
+        if coroutines.iscoroutinefunction(callback):
+            raise TypeError("coroutines cannot be used with call_soon()")
         self._check_signal(sig)
         try:
             # set_wakeup_fd() raises ValueError if this is not the
diff --git a/Lib/test/test_asyncio/test_unix_events.py b/Lib/test/test_asyncio/test_unix_events.py
index e397598..2f3fa18 100644
--- a/Lib/test/test_asyncio/test_unix_events.py
+++ b/Lib/test/test_asyncio/test_unix_events.py
@@ -64,6 +64,18 @@ class SelectorEventLoopSignalTests(test_utils.TestCase):
             signal.SIGINT, lambda: True)
 
     @mock.patch('asyncio.unix_events.signal')
+    def test_add_signal_handler_coroutine_error(self, m_signal):
+
+        @asyncio.coroutine
+        def simple_coroutine():
+            yield from []
+
+        self.assertRaises(
+            TypeError,
+            self.loop.add_signal_handler,
+            signal.SIGINT, simple_coroutine)
+
+    @mock.patch('asyncio.unix_events.signal')
     def test_add_signal_handler(self, m_signal):
         m_signal.NSIG = signal.NSIG
 
diff --git a/Misc/NEWS b/Misc/NEWS
index ef98134..97ad428 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -183,6 +183,9 @@ Core and Builtins
 Library
 -------
 
+- Issue #22841: Reject coroutines in asyncio add_signal_handler().
+  Patch by Ludovic.Gasc.
+
 - Issue #19494: Added urllib.request.HTTPBasicPriorAuthHandler. Patch by
   Matej Cepl.