1 files changed, 71 insertions, 2 deletions
diff --git a/Lib/test/test_asyncio/test_tasks.py b/Lib/test/test_asyncio/test_tasks.py
index 8d7f1733454..f6f976f213a 100644
--- a/Lib/test/test_asyncio/test_tasks.py
+++ b/Lib/test/test_asyncio/test_tasks.py
@@ -89,8 +89,8 @@ class BaseTaskTests:
     Future = None
     all_tasks = None
 
-    def new_task(self, loop, coro, name='TestTask', context=None):
-        return self.__class__.Task(coro, loop=loop, name=name, context=context)
+    def new_task(self, loop, coro, name='TestTask', context=None, eager_start=None):
+        return self.__class__.Task(coro, loop=loop, name=name, context=context, eager_start=eager_start)
 
     def new_future(self, loop):
         return self.__class__.Future(loop=loop)
@@ -2116,6 +2116,46 @@ class BaseTaskTests:
         self.assertTrue(outer.cancelled())
         self.assertEqual(0, 0 if outer._callbacks is None else len(outer._callbacks))
 
+    def test_shield_cancel_outer_result(self):
+        mock_handler = mock.Mock()
+        self.loop.set_exception_handler(mock_handler)
+        inner = self.new_future(self.loop)
+        outer = asyncio.shield(inner)
+        test_utils.run_briefly(self.loop)
+        outer.cancel()
+        test_utils.run_briefly(self.loop)
+        inner.set_result(1)
+        test_utils.run_briefly(self.loop)
+        mock_handler.assert_not_called()
+
+    def test_shield_cancel_outer_exception(self):
+        mock_handler = mock.Mock()
+        self.loop.set_exception_handler(mock_handler)
+        inner = self.new_future(self.loop)
+        outer = asyncio.shield(inner)
+        test_utils.run_briefly(self.loop)
+        outer.cancel()
+        test_utils.run_briefly(self.loop)
+        inner.set_exception(Exception('foo'))
+        test_utils.run_briefly(self.loop)
+        mock_handler.assert_called_once()
+
+    def test_shield_duplicate_log_once(self):
+        mock_handler = mock.Mock()
+        self.loop.set_exception_handler(mock_handler)
+        inner = self.new_future(self.loop)
+        outer = asyncio.shield(inner)
+        test_utils.run_briefly(self.loop)
+        outer.cancel()
+        test_utils.run_briefly(self.loop)
+        outer = asyncio.shield(inner)
+        test_utils.run_briefly(self.loop)
+        outer.cancel()
+        test_utils.run_briefly(self.loop)
+        inner.set_exception(Exception('foo'))
+        test_utils.run_briefly(self.loop)
+        mock_handler.assert_called_once()
+
     def test_shield_shortcut(self):
         fut = self.new_future(self.loop)
         fut.set_result(42)
@@ -2686,6 +2726,35 @@ class BaseTaskTests:
 
         self.assertEqual([None, 1, 2], ret)
 
+    def test_eager_start_true(self):
+        name = None
+
+        async def asyncfn():
+            nonlocal name
+            name = self.current_task().get_name()
+
+        async def main():
+            t = self.new_task(coro=asyncfn(), loop=asyncio.get_running_loop(), eager_start=True, name="example")
+            self.assertTrue(t.done())
+            self.assertEqual(name, "example")
+            await t
+
+    def test_eager_start_false(self):
+        name = None
+
+        async def asyncfn():
+            nonlocal name
+            name = self.current_task().get_name()
+
+        async def main():
+            t = self.new_task(coro=asyncfn(), loop=asyncio.get_running_loop(), eager_start=False, name="example")
+            self.assertFalse(t.done())
+            self.assertIsNone(name)
+            await t
+            self.assertEqual(name, "example")
+
+        asyncio.run(main(), loop_factory=asyncio.EventLoop)
+
     def test_get_coro(self):
         loop = asyncio.new_event_loop()
         coro = coroutine_function()