repository·master·Indexed 20 days ago
https://github.com/minitest/minitest-railsIntegration for Minitest within Rails that enables the Minitest::Spec DSL within standard Rails TestCase classes. It provides Rails generators for models and scaffolds, automatic base class selection via spec types (such as :model, :job, and :mailer), and specialized expectations for ActionCable and ActiveSupport, including must_change and must_differ.
The minitest-rails gem follows Rails versioning. To ensure compatibility, match your minitest-rails version to your Rails version:
minitest-rails 6.0.x is for rails 6.0.x.minitest-rails 6.1.x is for rails 6.1.x.In newer versions of minitest-rails, the expectation for checking changes has been updated to align with Rails' assert_changes assertion.
must_differ to wrap the assert_changes assertion (standard for Rails 5.1+).must_change expectation, which previously referred to assert_difference, is no longer the primary way to check for changes in this context.# Use must_differ for modern Rails change assertions
subject.must_differ do
# code that causes a change
endAfter adding the gem to your Gemfile and running bundle install, run the installation generator to set up the necessary test infrastructure. This will create a test_helper.rb file in your test/ directory.
rails generate minitest:installWhen using the Spec DSL, pass the actual class/constant to the describe block rather than its name as a string. If you must use a string, you must explicitly provide the :controller symbol as an additional argument to specify the test class type.
Correct usage:
describe WidgetsController doIncorrect usage:
describe "WidgetsController" doUsage with string name:
describe "WidgetsController", :controller doBy default, minitest-rails enables the Minitest::Spec DSL within Rails TestCase classes (like ActiveSupport::TestCase). When you use standard Rails generators (model, controller, etc.), they will generate tests using the Spec DSL.
Minitest::Spec DSL, use the --no-spec flag.--skip-fixture flag.You can configure your Rails application to always use standard Minitest (without Spec DSL) and skip fixtures by adding the following to config/application.rb:
config.generators do |g|
g.test_framework :minitest, spec: false, fixture: false
end# Example: Generating a model with Spec DSL (default)
rails generate model User
# Example: Generating a model without Spec DSL
rails generate model User --no-spec
# Example: Generating a model without a fixture
rails generate model User --skip-fixtureTo install the gem directly, use the following command. Note that this also installs the minitest gem as a dependency.
gem install minitest-railsMinitest-rails uses register_spec_type to automatically select the correct Rails TestCase base class based on how you describe your tests. You can trigger this in two ways:
describe inherits from a specific Rails component (e.g., ActiveRecord::Base), the correct base class is used.describe block to force a specific base class.Supported mappings include:
| Symbol | Base Class | Component |
|---|---|---|
:model | ActiveSupport::TestCase | ActiveRecord / Models |
:view or :helper | ActionView::TestCase | ActionView / Helpers |
:job | ActiveJob::TestCase | ActiveJob |
:mailer | ActionMailer::TestCase | ActionMailer |
:integration | ActionDispatch::IntegrationTest | ActionDispatch / Integration |
:generator | Rails::Generators::TestCase | Rails Generators |
:channel | ActionCable::Channel::TestCase | ActionCable Channels |
:connection | ActionCable::Connection::TestCase | ActionCable Connections |
# Using symbols to specify the base class
describe "My Mailer", :mailer do
it "sends an email" do
# ...
end
end
# Using symbols for integration tests
describe "User Flow", :integration do
# ...
endWhen minitest-rails is loaded, it extends ActiveSupport::TestCase with the Minitest::Spec::DSL. This allows you to write tests using the describe/it syntax instead of standard class-based unit tests. Additionally, it includes ActiveSupport::Testing::ConstantLookup, which allows the spec DSL to resolve constants from the test name.
# Example of using the spec DSL in a Rails environment
describe User do
it "is valid with a name" do
user = User.new(name: "Alice")
assert user.valid?
end
endThe minitest-rails gem follows Rails versioning. You should specify a version in your Gemfile that matches your current Rails version to ensure compatibility.
Examples:
gem "minitest-rails", "~> 8.1.0"gem "minitest-rails", "~> 7.2.0"gem "minitest-rails", "~> 6.0.0"gem "minitest-rails", "~> 8.1.0"You can enable minitest/hell by setting the MT_HELL environment variable. This is typically used for testing the robustness of your test suite by introducing randomness or other disruptive behaviors.
MT_HELL=true bundle exec rails testYou can use the minitest:install Rails generator to set up the necessary directory structure and configuration files for minitest-rails in your application. This generator creates standard test directories (fixtures, controllers, mailers, models, helpers, integration) and populates test/test_helper.rb, test/application_system_test_case.rb, and test/channels/application_cable/connection_test.rb.
To skip the creation of Active Record related files, use the --skip_active_record flag.
rails generate minitest:install
# To skip Active Record files:
rails generate minitest:install --skip_active_recordTo execute your test suite, use the standard Rails test command:
rails test