The specific answer here is probably not important in and of itself – What’s important is that you can demonstrate familiarity with at least several testing tools, and be able to discuss their individual advantages and weaknesses. Never ventured outside of Rails default testing tools? Take some time to familiarize yourself with tools such as Rspec, FactoryGirl, Capybara, and Cucumber
Be sure to be able to discuss a list of your favorite gems, why you like them, and any customizations you like to add. This is also a good opportunity to highlight any gems you may have published.
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