Merge pull request #1390 from ESMCI/jgfouca/fix_bug_in_errput_run_cmd

Errput may be empty string or None

scripts/lib/CIME/utils.py

@@ -259,7 +259,7 @@ def run_cmd_no_fail(cmd, input_str=None, from_dir=None, verbose=None,
     if stat != 0:
         # If command produced no errput, put output in the exception since we
         # have nothing else to go on.
-        errput = output if errput == "" else errput
+        errput = output if not errput else errput
         expect(False, "Command: '%s' failed with error '%s'%s" %
                (cmd, errput, "" if from_dir is None else " from dir '%s'" % from_dir))