Testing tools

LesliTesting configures a set of tools around standard Minitest. The project still owns its test cases, assertions, fixtures, and Rails test environment.

Minitest reporter

The custom reporter replaces the default Minitest reporter and prints:

• A status line for each test unless quiet mode is enabled
• PASS, SKIP, FAIL, or ERROR labels
• Test class and method names
• Assertion counts
• Execution time for tests taking more than one second
• Totals for tests, passes, failures, errors, skips, assertions, success rate, and duration
• Formatted locations and assertion details for failures

Assertion counts are color-coded to make tests with very few assertions easy to spot. This is guidance in the terminal output; it does not change whether a test passes.

Set QUIET=true to suppress per-test lines while keeping the final summary and failure information:

QUIET=true bundle exec rake

Coverage

Coverage is disabled during ordinary test runs. Set COVERAGE to any value to start SimpleCov:

COVERAGE=true bundle exec rake

Every coverage run produces:

The minimum line-coverage threshold defaults to 90 percent. Configure it for a suite with coverage_min_coverage:

LesliTesting.gem(
  "MyGem",
  coverage_min_coverage: 85
)

The coverage process exits unsuccessfully when the result is below the configured threshold.

Use coverage_missing_len to limit the length of missing-line details in the console formatter:

LesliTesting.engine(
  "MyEngine",
  coverage_missing_len: 40
)

Set it to 0 to remove the limit.

Environment variables

COVERAGE and QUIET are enabled by presence. Do not set them to false; leave them unset when the behavior should be disabled.

Shared Rails test classes

The shared classes are defined only when their corresponding Rails classes have already been loaded.

IntegrationTester

LesliTesting::IntegrationTester inherits from ActionDispatch::IntegrationTest and includes response helpers:

class AccountsControllerTest < LesliTesting::IntegrationTester
  test "returns JSON" do
    get accounts_url, as: :json

    expect_response_with_successful
    assert_kind_of Array, response_json
  end
end

Available helpers:

ModelTester

LesliTesting::ModelTester inherits from ActiveSupport::TestCase and includes ActiveSupport::Testing::TimeHelpers:

class SubscriptionTest < LesliTesting::ModelTester
  test "expires tomorrow" do
    travel_to Time.zone.local(2026, 9, 26, 12) do
      assert_equal Date.new(2026, 9, 27), Subscription.expires_tomorrow
    end
  end
end

ViewTester

LesliTesting::ViewTester inherits from ActionView::TestCase. When available, subclasses receive Lesli::HtmlHelper and Lesli::SystemHelper:

class NavigationHelperTest < LesliTesting::ViewTester
  test "renders navigation" do
    assert_includes render_navigation, "Dashboard"
  end
end

Lesli fixtures

When Lesli is loaded, LesliTesting registers the Lesli engine's fixture directory and file-fixture directory with ActiveSupport::TestCase. It also maps these fixture sets to their namespaced models:

The fixture integration runs during configuration. Load the Rails environment and the Lesli engine before calling the profile method when the suite depends on these shared fixtures.

Engine-specific fixture paths remain the responsibility of the engine test helper. See Testing Rails engines for an example.