Rspec has argument matchers any_args for matching any number of args at any point in an arg list and anything for matching anything and everything.

Capybara defaults to requiring an href attribute exist when finding links. To handle such cases we can pass href: nil as an option thus enabling to find it.

Rails has an ActiveSupport::Notifications module which is a part of its core instrumentation API. This API allows users to define hooks on events. With the ActiveSupport::Notifications you can instrument an event by simply calling instrument with a name, payload and a block. The notification will be sent after the block returns. Now all you need is to define subscribe method which consumes the event based on event name and you can define your on callback code here, sort of like a Pub/sub pattern.

you can pass options.args << ‘--headless’ to firefox newer versions, no need for headless gem

options = Selenium::WebDriver::Firefox::Options.new options.args << ‘--headless’ Capybara::Selenium::Driver.new(app,browser: :firefox, options: options)

To remove unwanted hex packages from mix.lock file, use mix deps.unlock --unused command

You can switch between k8s contexts using the docker toolbar menu in OSX.