Ruby Testing

This file extends common/testing.md with Ruby and Rails specific content.

Framework

• Use Minitest when the Rails app follows the default Rails test stack.
• Use RSpec when it is already established in the project or the team has explicit production conventions around it.
• Do not mix Minitest and RSpec inside the same feature area without a migration reason.

Test Pyramid

• Put fast domain behavior in model, service, query, policy, and job tests.
• Use request/controller tests for HTTP contracts, auth behavior, redirects, status codes, and response shapes.
• Use system tests with Capybara for browser-critical flows only; keep them focused and stable.
• Cover background jobs with unit tests for behavior and integration tests for queue/enqueue contracts.

Fixtures And Factories

• Use Rails fixtures when they are the project default and the data graph is small.
• Use factory_bot when scenarios need explicit object construction or complex traits.
• Keep test data close to the behavior being asserted; avoid global fixtures that hide setup cost.

Commands

Prefer project-local commands:

bin/rails test
bin/rails test test/models/user_test.rb
bundle exec rspec
bundle exec rspec spec/models/user_spec.rb

Coverage

• Use SimpleCov when coverage is enforced; keep thresholds in CI and avoid gaming branch coverage with low-value tests.
• Add regression tests for bug fixes before changing production code.

Reference

See skill: tdd-workflow for the repo-wide RED -> GREEN -> REFACTOR loop.