The parameter passed to Module.included is always a Module so the check for deciding if the library should inject the ModuleMethods was not doing any checks at all.
Since a Class is always also a Module, the check should check to see if the parameter is not a Class instead. This makes sure that ModuleMethods is only included into modules and never to classes.
I also added a test to verify these expectations explicitly.
The parameter passed to
Module.includedis always aModuleso the check for deciding if the library should inject theModuleMethodswas not doing any checks at all.Since a
Classis always also aModule, the check should check to see if the parameter is not aClassinstead. This makes sure thatModuleMethodsis only included into modules and never to classes.I also added a test to verify these expectations explicitly.