Dont print to sdout in unit tests.

Since the logs module was imported early it was using the wrong `sys.stderr`, so you would still get logspew in stderr during the test, which throws off the test reporting.

This commit uses the inspect module to figure out if we're running in a unit test and doesnt add the stream/file handler to the logger when that happens, meaning only the capture handler gets used.

ice/logs.py

@@ -6,8 +6,9 @@
 Copyright (c) 2013 Scott Rice. All rights reserved.
 """
 
-import sys
+import inspect
 import os
+import sys
 import time
 import traceback
 
@@ -16,6 +17,16 @@
 
 import paths
 
+def is_test_stack_frame(frame):
+  # The path of the executing file is in frame[1]
+  path = frame[1]
+  # See if the path is in the unittest module
+  return "unittest" in path
+
+def is_running_in_test():
+  current_stack = inspect.stack()
+  return any(map(is_test_stack_frame, inspect.stack()))
+
 class IceLevelTagFilter(logging.Formatter):
 
   def _tag_for_level(self, levelno):
@@ -47,8 +58,9 @@ def create_logger():
     # loggers
     logger = logging.getLogger('Ice')
     logger.setLevel(logging.DEBUG)
-    logger.addHandler(ch)
-    logger.addHandler(fh)
+    if not is_running_in_test():
+      logger.addHandler(ch)
+      logger.addHandler(fh)
     return logger
 
 logger = create_logger()