fix logic error and prep for release

Author: barryorourke

CHANGELOG.md

@@ -3,6 +3,10 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 
 This CHANGELOG follows the format listed [here](https://github.com/sensu-plugins/community/blob/master/HOW_WE_CHANGELOG.md)
 
+## [0.3.1] 2017-10-10
+### Fixed
+- Really obvious logical error introduced whilst making 0.3.0 pass tests (@barryorourke)
+
 ## [0.3.0] 2017-10-06
 ### Breaking Change
 - Dropped support for Python 3.3 (@barryorourke)

sensu_plugin/plugin.py

@@ -48,7 +48,7 @@ def __make_dynamic(self, method):
 
         def dynamic(*args):
             self.plugin_info['status'] = method
-            if args:
+            if not args:
                 args = None
             self.output(args)
             sys.exit(getattr(self.exit_code, method))