Beginners Guide to Test Driven Development

Learn the basics of test driven development by writing tests first before implementing code. See how red, green, and refactor cycles guide development, and how given-when-then scenarios define expected behavior.

Explore the three test types used in test driven development: unit tests, integration tests, and functional tests, with emphasis on independence, edge cases, and correct output.

Learn how Rails uses the built-in Minitest framework to drive tests across models, controllers, mailers, and system tests, and compare RSpec and Cucumber as alternatives.

Lay the foundation of test-driven development by preparing a Rails app, configuring development and test gems, and setting up the test folder, helpers, and Capybara-based integration tests.

A beginner's guide to test driven development introduces building a user model, writing unit tests with Rails test or RSpec, and applying red-green-refactor cycles with fixtures and migrations.

Learn how test databases and fixtures work in Rails, using YAML fixtures to seed independent sample data that are automatically loaded during tests.

Explore how to set up fixture associations between users and subscriptions in a Rails app, create and validate subscription fixtures, and test data integrity using fixtures and specs.

Implement and test a sign-in flow by building a sessions controller, sign-in form with email and password, and functional tests to verify authentication and redirects.

Learn how functional tests manage cookies and authentication in a Rails app, ensuring authenticated users are redirected when accessing restricted pages and receive a flash message.

Develop functional tests to verify subscription creation in a controller, asserting the subscriptions count changes by one, handling authentication, redirects, and success messages.

Demonstrate integration tests for sign in, sign out, and authorized access to the subscriptions page, validating redirects, rendering, and proper credential handling within a tdd basics context.

Explore integration tests that validate the registration process, posting user credentials (email and password), verifying redirects, and checking the complete registration flow within a test driven development workflow.

Explore integration testing of subscription creation in a Rails app, validating user creation, redirects, and forms for subscribing and managing subscriptions.

Explore setting up system tests with Capybara in Rails 5.1, comparing Selenium and headless Poltergeist, and understand Database Cleaner alternatives for test isolation.

Write and run your first system test for user registration using Rails, Capybara, and Selenium, validating form fields, submission, and welcome page.

Write system tests for signing in and signing out using fixtures and proper credentials, verify redirects to the sign-in page, and assert success messages and navigation.

Write tests to exercise the subscriptions feature in a tdd workflow, validating that a user can subscribe to categories via a dropdown and cannot subscribe twice, with assertions and screenshots.

Test mailers in Rails using before_action inside mailers, with subscriptions and user notifications. Create tests and fixtures with previews to verify subject, to address, from address, and email body.

Explore using background jobs to perform actions asynchronously, such as sending emails and notifications, with queuing, scheduling, and testing strategies, including assertions and test helpers for active jobs.

Test third party services by recording and replaying API interactions with VCR, using cassettes to avoid real requests in tests and speed up integration tests.

Discover how to test third party services using VCR cassettes in Rails, handle redirects, ignore local requests, and ensure reliable system and integration tests for subscriptions and currency rates.

Wraps up the course by reviewing test driven development and key test types—unit, functional, integration, and system tests—plus testing background jobs, mailers, and third-party services.