tests: handle DependencyException

some eventloops if fail to be imported, now raises this new
`DependencyException`, and test should be able to be skipped based
on that

Author: fruch

tests/unit/io/test_asyncorereactor.py

@@ -15,11 +15,13 @@
 
 from mock import patch
 import socket
+
+from cassandra import DependencyException
 try:
     import cassandra.io.asyncorereactor as asyncorereactor
     from cassandra.io.asyncorereactor import AsyncoreConnection
     ASYNCCORE_AVAILABLE = True
-except ImportError:
+except (ImportError, DependencyException):
     ASYNCCORE_AVAILABLE = False
     AsyncoreConnection = None
 

tests/unit/io/test_libevreactor.py

@@ -21,10 +21,11 @@
 from tests.unit.io.utils import ReactorTestMixin, TimerTestMixin, noop_if_monkey_patched
 
 
+from cassandra import DependencyException
 try:
     from cassandra.io.libevreactor import _cleanup as libev__cleanup
     from cassandra.io.libevreactor import LibevConnection
-except ImportError:
+except (ImportError, DependencyException):
     LibevConnection = None  # noqa