testing-language

Testing Language Standards

Standards for language handling in tests

Configuration

1. Test Environment Setup

# test/test_helper.rb
module ActiveSupport
  class TestCase
    # Run tests in parallel
    parallelize(workers: :number_of_processors)

    # Include FactoryBot syntax methods
    include FactoryBot::Syntax::Methods

    # Force English locale for all tests
    setup do
      I18n.locale = :en
      I18n.default_locale = :en
      Rails.application.config.i18n.default_locale = :en
      Rails.application.config.i18n.locale = :en
      Rails.application.config.i18n.available_locales = [:en, :de]
    end

    teardown do
      I18n.locale = :en
    end
  end
end

1. Application Controller

# app/controllers/application_controller.rb
class ApplicationController < ActionController::Base
  before_action :set_locale

  private

  def set_locale
    return if Rails.env.test? # Skip locale detection in test environment
    I18n.locale = extract_locale_from_accept_language_header || I18n.default_locale
  end
end

Factory Setup

1. User Factory

# test/factories/users.rb
FactoryBot.define do
  factory :user do
    first_name { Faker::Name.first_name }
    last_name { Faker::Name.last_name }
    email { Faker::Internet.email }
    password { "password123" }
    lang { "en" }  # Default to English

    trait :german do
      lang { "de" }
      after(:build) do |user|
        # Use German Faker data for consistency
        Faker::Config.locale = "de"
        user.first_name = Faker::Name.first_name
        user.last_name = Faker::Name.last_name
        Faker::Config.locale = "en"  # Reset to English
      end
    end
  end
end

Testing Guidelines

1. Translation Testing

# test/models/article_test.rb
class ArticleTest < ActiveSupport::TestCase
  test "article title is translated" do
    article = create(:article, title_en: "English Title", title_de: "Deutscher Titel")

    # Always test English first
    assert_equal "English Title", article.title

    # Test other languages explicitly
    I18n.with_locale(:de) do
      assert_equal "Deutscher Titel", article.title
    end

    # Reset to English
    assert_equal "English Title", article.title
  end
end