Fixed the cancellation mechanism

experiment.py

@@ -5,12 +5,12 @@ loop = giambio.EventLoop()
 
 """
 
-What works and what does not (21st March 2020 10:33 AM)
+What works and what does not (21st March 2020 11:22 AM)
 
 - Run tasks concurrently: V
 - Join mechanism: V
 - Sleep mechanism: V
-- Cancellation mechanism: X  Note: giambio.exceptions.CancelledError is raised inside the parent task instead of the child one, probably related to some f*ck ups with the value of EventLoop.running, need to investigate
+- Cancellation mechanism: V
 - Exception propagation: V
 - Concurrent I/O: X   Note: I/O would work only when a task is joined (weird)
 - Return values of coroutines: X     Note: Return values ARE actually stored in task objects properly, but are messed up later when joining tasks
@@ -26,7 +26,7 @@ async def countdown(n):
             await giambio.sleep(1)
         print("Countdown over")
         return "Count DOWN over"
-    except CancelledError:
+    except giambio.exceptions.CancelledError:
         print("countdown cancelled!")
 
 async def count(stop, step=1):
@@ -43,8 +43,7 @@ async def main():
     print("Spawning countdown immediately, scheduling count for 2 secs from now")
     task = loop.spawn(countdown(8))
     task1 = loop.schedule(count(12, 2), 2)
-    await task.join()
-    await task1.join()
-    print("All done")
+    await giambio.sleep(2)  # Wait before cancelling
+    await task.cancel()  # Cancel the task
 
 loop.start(main)

giambio/core.py

@@ -51,9 +51,8 @@ class EventLoop:
                 except StopIteration as e:   # TODO: Fix this return mechanism, it looks like the return value of the child task gets "replaced" by None at some point
                     self.running.ret_value = e.args[0] if e.args else None  # Saves the return value
                     self.to_run.extend(self.joined.pop(self.running, ()))  # Reschedules the parent task
-                except CancelledError:
-                    self.running.cancelled = True  # Update the coroutine status
-                    raise      # TODO: Fix this, removing this raises RuntimeError: cannot reuse already awaited coroutine
+                except RuntimeError:
+                    self.running.cancelled = True
                 except Exception as has_raised:
                     self.to_run.extend(self.joined.pop(self.running, ()))  # Reschedules the parent task
                     if self.running.joined:    # Let the join function handle the hassle of propagating the error