Make Future/Task compatible with asyncio in Python 3.6

uvloop/future.pyx

@@ -5,6 +5,22 @@ DEF _FUT_CANCELLED = 2
 DEF _FUT_FINISHED = 3
 
 
+cdef inline _future_get_blocking(fut):
+    try:
+        return fut._asyncio_future_blocking
+    except AttributeError:
+        return fut._blocking
+
+
+cdef inline _future_set_blocking(fut, val):
+    try:
+        fut._asyncio_future_blocking
+    except AttributeError:
+        fut._blocking = val
+    else:
+        fut._asyncio_future_blocking = val
+
+
 cdef class BaseFuture:
     cdef:
         int _state
@@ -36,6 +52,13 @@ cdef class BaseFuture:
         else:
             self._source_traceback = None
 
+    property _asyncio_future_blocking:
+        def __get__(self):
+            return self._blocking
+
+        def __set__(self, value):
+            self._blocking = value
+
     cdef _schedule_callbacks(self):
         cdef:
             list callbacks

uvloop/task.pyx

@@ -156,8 +156,8 @@ cdef class BaseTask(BaseFuture):
                 # Yielded Future must come from Future.__iter__().
                 if result._loop is not self._loop:
                     self._raise_wrong_loop(result)
-                elif result._blocking:
-                    result._blocking = False
+                elif _future_get_blocking(result):
+                    _future_set_blocking(result, False)
                     result.add_done_callback(self._wakeup)
                     self._fut_waiter = result
                     if self._must_cancel: