End-to-end testing with RSpec integration tests and Capybara

Stability can become an issue as web applications evolve and grow — integration tests provide a great way to perform end-to-end tests that validate the application is performing as expected.

Integration test with rspec and capybara

When writing integration tests, try to model the test around an actor (user of the system) and the action they are performing.

# spec/features/visitor_signs_up_spec.rb
require 'spec_helper'

feature 'Visitor signs up' do
  scenario 'with valid email and password' do
    sign_up_with 'valid@example.com', 'password'

    expect(page).to have_content('Sign out')
  end

  scenario 'with invalid email' do
    sign_up_with 'invalid_email', 'password'

    expect(page).to have_content('Sign in')
  end

  scenario 'with blank password' do
    sign_up_with 'valid@example.com', ''

    expect(page).to have_content('Sign in')
  end 

  def sign_up_with(email, password)
    visit sign_up_path
    fill_in 'Email', with: email
    fill_in 'Password', with: password
    click_button 'Sign up'
  end
end

Extracting common test functionality

To share code between features move common capybara steps into a Ruby module in the rspec support directory.

# spec/support/features/session_helpers.rb
module Features
  module SessionHelpers
    def sign_up_with(email, password)
      visit sign_up_path
      fill_in 'Email', with: email
      fill_in 'Password', with: password
      click_button 'Sign up'
    end

    def sign_in
      user = create(:user)
      visit sign_in_path
      fill_in 'Email', with: user.email
      fill_in 'Password', with: user.password
      click_button 'Sign in'
    end
  end
end

Modules must be explicitly included to share the common code between integration tests.

# spec/support/features.rb
RSpec.configure do |config|
  config.include Features::SessionHelpers, type: :feature
end

Running the integration tests

$ rspec -fd
Visitor signs up
  with valid email and password
  with invalid email
  with blank password

Finished in 0.35837 seconds
3 examples, 0 failures

Takeaways

• Maintain application stability with end-to-end test coverage
• Use RSpec to run your integration tests
• Modules allow shared Capybara steps between specs

By Harlow Ward

Next Steps & Related Reading

Describe the User’s Perspective: DDD, acceptance testing, and you

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