Disable validation in test environment

[SideofClouds]

There should be an option to disable the validation entirely when testing (make it always return true) in the test environment or in the config file. I'm using Rspec.
For now in my controller specs i just use "controller.stub(:captcha_valid?).and_return(true)" but for some reason that doesn't work in my feature spec ... and I tried writing it in many ways:
allow(UserRegistrationController).to receive(:captcha_valid?).and_return true
UserRegistrationController.stub(:captcha_valid?).and_return(true)
... not working.
Some help would be greatly appreciated.
Thank you,
Dan

[SideofClouds]

In the end I managed to bypass the validation in my feature spec using "UserRegistrationController.any_instance.stub(:captcha_valid?).and_return(true)" ... but the validation still needs to be disabled in the test environment by default so that there won't be a need to keep stubbing it.