# Testing Standards and Style Guidelines This guide outlines standards and best practices for automated testing of GitLab CE and EE. It is meant to be an _extension_ of the [thoughtbot testing styleguide](https://github.com/thoughtbot/guides/tree/master/style/testing). If this guide defines a rule that contradicts the thoughtbot guide, this guide takes precedence. Some guidelines may be repeated verbatim to stress their importance. ## Factories GitLab uses [factory_girl] as a test fixture replacement. - Factory definitions live in `spec/factories/`, named using the pluralization of their corresponding model (`User` factories are defined in `users.rb`). - There should be only one top-level factory definition per file. - FactoryGirl methods are mixed in to all RSpec groups. This means you can (and should) call `create(...)` instead of `FactoryGirl.create(...)`. - Make use of [traits] to clean up definitions and usages. - When defining a factory, don't define attributes that are not required for the resulting record to pass validation. - When instantiating from a factory, don't supply attributes that aren't required by the test. - Factories don't have to be limited to `ActiveRecord` objects. [See example](https://gitlab.com/gitlab-org/gitlab-ce/commit/0b8cefd3b2385a21cfed779bd659978c0402766d). [factory_girl]: https://github.com/thoughtbot/factory_girl [traits]: http://www.rubydoc.info/gems/factory_girl/file/GETTING_STARTED.md#Traits ## JavaScript GitLab uses [Teaspoon] to run its [Jasmine] JavaScript specs. They can be run on the command line via `bundle exec teaspoon`, or via a web browser at `http://localhost:3000/teaspoon` when the Rails server is running. - JavaScript tests live in `spec/javascripts/`, matching the folder structure of `app/assets/javascripts/`: `app/assets/javascripts/behaviors/autosize.js.coffee` has a corresponding `spec/javascripts/behaviors/autosize_spec.js.coffee` file. - Haml fixtures required for JavaScript tests live in `spec/javascripts/fixtures`. They should contain the bare minimum amount of markup necessary for the test. > **Warning:** Keep in mind that a Rails view may change and invalidate your test, but everything will still pass because your fixture doesn't reflect the latest view. - Keep in mind that in a CI environment, these tests are run in a headless browser and you will not have access to certain APIs, such as [`Notification`](https://developer.mozilla.org/en-US/docs/Web/API/notification), which will have to be stubbed. [Teaspoon]: https://github.com/modeset/teaspoon [Jasmine]: https://github.com/jasmine/jasmine ## RSpec ### General Guidelines - Use a single, top-level `describe ClassName` block. - Use `described_class` instead of repeating the class name being described. - Use `.method` to describe class methods and `#method` to describe instance methods. - Use `context` to test branching logic. - Don't `describe` symbols (see [Gotchas](gotchas.md#dont-describe-symbols)). - Don't supply the `:each` argument to hooks since it's the default. - Prefer `not_to` to `to_not` (_this is enforced by Rubocop_). - Try to match the ordering of tests to the ordering within the class. - Try to follow the [Four-Phase Test][four-phase-test] pattern, using newlines to separate phases. [four-phase-test]: https://robots.thoughtbot.com/four-phase-test ### `let` variables GitLab's RSpec suite has made extensive use of `let` variables to reduce duplication. However, this sometimes [comes at the cost of clarity][lets-not], so we need to set some guidelines for their use going forward: - `let` variables are preferable to instance variables. Local variables are preferable to `let` variables. - Use `let` to reduce duplication throughout an entire spec file. - Don't use `let` to define variables used by a single test; define them as local variables inside the test's `it` block. - Don't define a `let` variable inside the top-level `describe` block that's only used in a more deeply-nested `context` or `describe` block. Keep the definition as close as possible to where it's used. - Try to avoid overriding the definition of one `let` variable with another. - Don't define a `let` variable that's only used by the definition of another. Use a helper method instead. [lets-not]: https://robots.thoughtbot.com/lets-not ### Test speed GitLab has a massive test suite that, without parallelization, can take more than an hour to run. It's important that we make an effort to write tests that are accurate and effective _as well as_ fast. Here are some things to keep in mind regarding test performance: - `double` and `spy` are faster than `FactoryGirl.build(...)` - `FactoryGirl.build(...)` and `.build_stubbed` are faster than `.create`. - Don't `create` an object when `build`, `build_stubbed`, `attributes_for`, `spy`, or `double` will do. Database persistence is slow! - Use `create(:empty_project)` instead of `create(:project)` when you don't need the underlying Git repository. Filesystem operations are slow! - Don't mark a feature as requiring JavaScript (through `@javascript` in Spinach or `js: true` in RSpec) unless it's _actually_ required for the test to be valid. Headless browser testing is slow! ### Features / Integration - Feature specs live in `spec/features/` and should be named `ROLE_ACTION_spec.rb`, such as `user_changes_password_spec.rb`. - Use only one `feature` block per feature spec file. - Use scenario titles that describe the success and failure paths. - Avoid scenario titles that add no information, such as "successfully." - Avoid scenario titles that repeat the feature title. ## Spinach (feature) tests GitLab [moved from Cucumber to Spinach](https://github.com/gitlabhq/gitlabhq/pull/1426) for its feature/integration tests in September 2012. As of March 2016, we are [trying to avoid adding new Spinach tests](https://gitlab.com/gitlab-org/gitlab-ce/issues/14121) going forward, opting for [RSpec feature](#features-integration) specs. Adding new Spinach scenarios is acceptable _only if_ the new scenario requires no more than one new `step` definition. If more than that is required, the test should be re-implemented using RSpec instead. --- [Return to Development documentation](README.md)