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Testing

OnDemand Loop uses a comprehensive testing strategy to ensure stability, correctness, and confidence when making changes.
The testing approach covers everything from low-level unit tests to full end-to-end workflows, allowing contributors to verify functionality at the right level of detail.

All tests run inside Docker for a consistent and reproducible environment.
They are integrated with CI/CD so every pull request is validated automatically.

Overview

The test suite is divided into layers:

  • Unit tests – verify models, services, and helpers in isolation.
  • Integration tests – check how components interact across boundaries (controllers, connectors).
  • System tests – simulate user flows in a real browser using Rails' built-in system test framework.
  • End-to-End (E2E) tests – Cypress tests that run against the full application stack (see E2E Tests).
  • Manual testing – systematic verification of user workflows and visual validation (see Manual Testing).

All Rails tests live under application/test and follow Rails conventions:

Directory Purpose
models/ Model behavior and validation
controllers/ HTTP request/response handling
services/ Business logic and helpers
connectors/ Repository-specific logic
integration/ Higher-level interactions
system/ Browser-driven Rails system tests
views/, helpers/, lib/, utils/ Other layers
fixtures/ Sample data for deterministic tests

Tests use Minitest with Mocha for mocking.

Running Tests

Tests run inside a Docker container using the provided Makefile targets.

Common Targets

  • make test_bash – open an interactive shell inside the test container.
  • make test_exec – run commands non-interactively (piped via echo).
  • make coverage – run the test suite with code coverage enabled.

Run the full suite

echo 'bundle exec rake test' | make test_exec

Run a single test file

echo 'bundle exec rake test TEST=test/models/application_disk_record_test.rb' | make test_exec

Run a specific test by line number

echo 'bundle exec rake test TEST=test/models/application_disk_record_test.rb:52' | make test_exec

Run all tests in a directory

echo 'bundle exec rake test TEST="test/services/**/*_test.rb"' | make test_exec

Use options (verbose, stop on failure, seed)

echo 'bundle exec rake test TESTOPTS="--verbose --stop-on-failure --seed=1234"' | make test_exec

Interactive Mode

For exploratory work, start a shell and run tests manually: 

make test_bash
bundle exec rake test

Code Coverage

OnDemand Loop uses SimpleCov to measure test coverage.
Coverage reports are helpful for identifying untested code paths and ensuring contributions maintain a high level of reliability.

To generate a coverage report:

echo 'bundle exec rake test:coverage' | make test_exec

or simply:

make coverage

After running, open the generated report at: 

application/tmp/coverage/index.html

Best Practices

  • Keep tests fast and isolated; prefer fixtures and mocks over external dependencies.
  • Use descriptive test names that explain behavior, not implementation.
  • Organize tests consistently with application code (mirror directory structure).
  • Add system tests for new UI workflows; add E2E tests when behavior depends on the full environment.
  • Run the full test suite locally before opening a pull request.
  • Complement automated testing with manual verification for user experience and visual validation.