Gem bundle throws wrong argument type error

I am trying to follow this tutorial and I get the following error which turns up no google results and I'm still too inexperienced to know how to fix it. Any suggestions?

ERROR: While executin开发者_如何学运维g gem ... (TypeError) wrong argument type Symbol (expected Proc)

I am not even sure what gem bundle does exactly so I am not sure where to look next.

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Don't know about the error but follow the projects documentation and see if it fixes it: http://github.com/auxesis/cucumber-nagios

As the documentation says gem bundle comes from bundler gem.

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I ended up moving over to my Windows PC to move forward with the tutorial. My macbook was throwing errors on almost every GEM installation so I gave up on trying to use ruby on it.