add values_len function

Author: ekouts

reframe/frontend/executors/policies.py

@@ -4,6 +4,7 @@
 # SPDX-License-Identifier: BSD-3-Clause
 
 import contextlib
+import functools
 import itertools
 import math
 import sys
@@ -17,6 +18,10 @@
                                         TaskEventListener, ABORT_REASONS)
 
 
+def values_len(d):
+    return functools.reduce(lambda l, r: l + len(r), d.values(), 0)
+
+
 def _cleanup_all(tasks, *args, **kwargs):
     for task in tasks:
         if task.ref_count == 0:
@@ -417,7 +422,7 @@ def exit(self):
         num_polls = 0
         t_start = datetime.now()
         while (self._running_tasks or self._waiting_tasks or
-               self._completed_tasks or sum(self._ready_tasks.values(), [])):
+               self._completed_tasks or values_len(self._ready_tasks)):
             getlogger().debug('running tasks: %s' % len(self._running_tasks))
             num_polls += len(self._running_tasks)
             try: