bpo-38785: Prevent asyncio from crashing (GH-17144)

if parent `__init__` is not called from a constructor of object derived from `asyncio.Future`

https://bugs.python.org/issue38785
(cherry picked from commit dad6be5ffe48beb74fad78cf758b886afddc7aed)

Co-authored-by: Andrew Svetlov <andrew.svetlov@gmail.com>

1 files changed, 4 insertions, 1 deletions

diff --git a/Lib/asyncio/futures.py b/Lib/asyncio/futures.py
index 98a5308e..9afda22 100644
--- a/Lib/asyncio/futures.py
+++ b/Lib/asyncio/futures.py
@@ -115,7 +115,10 @@ class Future:
 
     def get_loop(self):
         """Return the event loop the Future is bound to."""
-        return self._loop
+        loop = self._loop
+        if loop is None:
+            raise RuntimeError("Future object is not initialized.")
+        return loop
 
     def cancel(self):
         """Cancel the future and schedule callbacks.