Testing

  • We use RSpec and Capybara

  • Capybara is used for our feature tests. These use the Rack driver by default (faster) or the Gecko driver (installation required) when the js: true option is passed for a test.

  • Capybara is configured to run in headless mode but this can be toggled by commenting out app/spec/rails_helper.rb#L14

  • Capybara is configured to use Gecko driver for JavaScript tests as Chrome is more commonly used and so naturally more likely to be better tested but this can be switched to Chrome driver by changing app/spec/rails_helper.rb#L13

  • Feature specs are generally written sparingly as they’re also the slowest, where possible a request spec is preferred as this still tests a large surface area (route, controller, model, view) without the performance impact. They are not suitable for tests that need to run JavaScript or test that a specific set of interaction events that trigger a specific set of requests (with high confidence).

  • Test data is created with FactoryBot where ever possible

Parallel testing

  • The RSpec test suite can be ran in parallel in local development for quicker turnaround times

  • Setup with the following:

bundle exec rake parallel:setup
  • Run with:
RAILS_ENV=test bundle exec rake parallel:spec