Fix a bug where inactive loops would be indexed (read desc)

Cleaned up Aergia.walk_back_until_loop to only get running event loops. Previously, this manifested as a bug. The asyncio.Process class would fork off a thread, and the event loop would be found in that thread's local variables, even though that thread was not executing that event loop. This would result in get_event_loops containing duplicate values, and affected event loops would be assigned duplicate time

1 files changed, 17 insertions, 22 deletions

diff --git a/aergia/aergia.py b/aergia/aergia.py
index b7b4f35..ad283e0 100755
--- a/aergia/aergia.py
+++ b/aergia/aergia.py
@@ -175,35 +175,30 @@ class Aergia(object):
 
     @staticmethod
     def get_event_loops():
-        '''Obtains each thread's event loop by relying on the fact that
-        if an event loop is active, it's own `run_once' and `run_forever'
-        will appear in the callstack.'''
+        '''Obtains each thread's event loop.'''
         loops = []
         for t in threading.enumerate():
             frame = sys._current_frames().get(t.ident)
-            if not frame:
-                continue
-            loops.extend(Aergia.walk_back_until_loops(frame))
+            if frame:
+                loop = Aergia.walk_back_until_loop(frame)
+                if loop and loop not in loops:
+                    loops.append(loop)
         return loops
 
     @staticmethod
-    def walk_back_until_loops(frame):
-        '''Walks back the callstack until all event loops are found.'''
-        loops = []
+    def walk_back_until_loop(frame):
+        '''Walks back the callstack until we are in a method named '_run_once'.
+        If this is ever true, we assume we are in an Asyncio event loop method,
+        and check to see if the 'self' variable is indeed and instance of
+        AbstractEventLoop. Return this variable if true.'''
         while frame:
-            loop = Aergia.find_loop_in_locals(frame.f_locals)
-            if loop and loop not in loops:  # Avoid duplicates
-                loops.append(loop)
-            frame = frame.f_back
-        return loops
-
-    @staticmethod
-    def find_loop_in_locals(locals_dict):
-        '''Given a dictionary of local variables for a stack frame,
-        retrieves the asyncio loop object, if there is one.'''
-        for val in locals_dict.values():
-            if isinstance(val, asyncio.AbstractEventLoop):
-                return val
+            if frame.f_code.co_name == '_run_once' and 'self' in frame.f_locals:
+                loop = frame.f_locals['self']
+                if isinstance(loop, asyncio.AbstractEventLoop):
+                    return loop
+            else:
+                # print(frame.f_code.co_name)
+                frame = frame.f_back
         return None
 
     @staticmethod