测试 Rails 应用程序

$ ls -F test
controllers/                     helpers/                         mailers/                         fixtures/                        integration/                     models/                          test_helper.rb

$ bin/rails generate model article title:string body:text
...
create  app/models/article.rb
create  test/models/article_test.rb
...

require "test_helper"

class ArticleTest < ActiveSupport::TestCase
  # test "the truth" do
  #   assert true
  # end
end

require "test_helper"

class ArticleTest < ActiveSupport::TestCase
  # ...
end

test "the truth" do
  assert true
end

def test_the_truth
  assert true
end

assert true

require "test_helper"

class ArticleTest < ActiveSupport::TestCase
  test "should not save article without title" do
    article = Article.new
    assert_not article.save
  end
end

$ bin/rails test test/models/article_test.rb
Running 1 tests in a single process (parallelization threshold is 50)
Run options: --seed 44656

# Running:

F

Failure:
ArticleTest#test_should_not_save_article_without_title [/path/to/blog/test/models/article_test.rb:4]:
Expected true to be nil or false


bin/rails test test/models/article_test.rb:4



Finished in 0.023918s, 41.8090 runs/s, 41.8090 assertions/s.

1 runs, 1 assertions, 1 failures, 0 errors, 0 skips

test "should not save article without title" do
  article = Article.new
  assert_not article.save, "Saved the article without a title"
end

Failure:
ArticleTest#test_should_not_save_article_without_title [/path/to/blog/test/models/article_test.rb:6]:
Saved the article without a title

class Article < ApplicationRecord
  validates :title, presence: true
end

$ bin/rails test test/models/article_test.rb:6
Running 1 tests in a single process (parallelization threshold is 50)
Run options: --seed 31252

# Running:

.

Finished in 0.027476s, 36.3952 runs/s, 36.3952 assertions/s.

1 runs, 1 assertions, 0 failures, 0 errors, 0 skips

test "should report error" do
  # some_undefined_variable is not defined elsewhere in the test case
  some_undefined_variable
  assert true
end

$ bin/rails test test/models/article_test.rb
Running 2 tests in a single process (parallelization threshold is 50)
Run options: --seed 1808

# Running:

E

Error:
ArticleTest#test_should_report_error:
NameError: undefined local variable or method 'some_undefined_variable' for #<ArticleTest:0x007fee3aa71798>
    test/models/article_test.rb:11:in 'block in <class:ArticleTest>'


bin/rails test test/models/article_test.rb:9

.

Finished in 0.040609s, 49.2500 runs/s, 24.6250 assertions/s.

2 runs, 1 assertions, 0 failures, 1 errors, 0 skips

$ bin/rails test -b test/models/article_test.rb

test "should report error" do
  # some_undefined_variable is not defined elsewhere in the test case
  assert_raises(NameError) do
    some_undefined_variable
  end
end

$ bin/rails test test/models/article_test.rb
Running 1 tests in a single process (parallelization threshold is 50)
Run options: --seed 1559

# Running:

..

Finished in 0.027034s, 73.9810 runs/s, 110.9715 assertions/s.

2 runs, 3 assertions, 0 failures, 0 errors, 0 skips

$ bin/rails test test/models/article_test.rb -n test_the_truth
Running 1 tests in a single process (parallelization threshold is 50)
Run options: -n test_the_truth --seed 43583

# Running:

.

Finished tests in 0.009064s, 110.3266 tests/s, 110.3266 assertions/s.

1 tests, 1 assertions, 0 failures, 0 errors, 0 skips

$ bin/rails test test/models/article_test.rb:6 # run specific test and line

$ bin/rails test test/models/article_test.rb:6-20 # runs tests from line 6 to 20

$ bin/rails test test/controllers # run all tests from specific directory

$ bin/rails test -h
Usage:
  bin/rails test [PATHS...]

Run tests except system tests

Examples:
    You can run a single test by appending a line number to a filename:

        bin/rails test test/models/user_test.rb:27

    You can run multiple tests with in a line range by appending the line range to a filename:

        bin/rails test test/models/user_test.rb:10-20

    You can run multiple files and directories at the same time:

        bin/rails test test/controllers test/integration/login_test.rb

    By default test failures and errors are reported inline during a run.

minitest options:
    -h, --help                       Display this help.
        --no-plugins                 Bypass minitest plugin auto-loading (or set $MT_NO_PLUGINS).
    -s, --seed SEED                  Sets random seed. Also via env. Eg: SEED=n rake
    -v, --verbose                    Verbose. Show progress processing files.
        --show-skips                 Show skipped at the end of run.
    -n, --name PATTERN               Filter run on /regexp/ or string.
        --exclude PATTERN            Exclude /regexp/ or string from run.
    -S, --skip CODES                 Skip reporting of certain types of results (eg E).

Known extensions: rails, pride
    -w, --warnings                   Run with Ruby warnings enabled
    -e, --environment ENV            Run tests in the ENV environment
    -b, --backtrace                  Show the complete backtrace
    -d, --defer-output               Output test failures and errors after the test run
    -f, --fail-fast                  Abort test run on first failure or error
    -c, --[no-]color                 Enable color in the output
        --profile [COUNT]            Enable profiling of tests and list the slowest test cases (default: 10)
    -p, --pride                      Pride. Show your testing pride!

# lo & behold! I am a YAML comment!
david:
  name: David Heinemeier Hansson
  birthday: 1979-10-15
  profession: Systems development

steve:
  name: Steve Ross Kellock
  birthday: 1974-09-27
  profession: guy with keyboard

# test/fixtures/categories.yml
web_frameworks:
  name: Web Frameworks

# test/fixtures/articles.yml
first:
  title: Welcome to Rails!
  category: web_frameworks

# test/fixtures/action_text/rich_texts.yml
first_content:
  record: first (Article)
  name: content
  body: <div>Hello, from <strong>a fixture</strong></div>

class Article < ApplicationRecord
  has_one_attached :thumbnail
end

# test/fixtures/articles.yml
first:
  title: An Article

# test/fixtures/active_storage/blobs.yml
first_thumbnail_blob: <%= ActiveStorage::FixtureSet.blob filename: "first.png" %>

# test/fixtures/active_storage/attachments.yml
first_thumbnail_attachment:
  name: thumbnail
  record: first (Article)
  blob: first_thumbnail_blob

<% 1000.times do |n| %>
  user_<%= n %>:
    username: <%= "user#{n}" %>
    email: <%= "user#{n}@example.com" %>
<% end %>

# this will return the User object for the fixture named david
users(:david)

# this will return the property for david called id
users(:david).id

# methods available to the User object can also be accessed
david = users(:david)
david.call(david.partner)

# this will return an array containing the fixtures david and steve
users(:david, :steve)

class MyTest < ActiveSupport::TestCase
  test "newly created users are active by default" do
    # Since the test is implicitly wrapped in a database transaction, the user
    # created here won't be seen by other tests.
    assert User.create.active?
  end
end

class MyTest < ActiveSupport::TestCase
  test "Active Record current_transaction method works as expected" do
    # The implicit transaction around tests does not interfere with the
    # application-level semantics of the current_transaction.
    assert User.current_transaction.blank?
  end
end

class MyTest < ActiveSupport::TestCase
  # No implicit database transaction wraps the tests in this test case.
  self.use_transactional_tests = false
end

$ bin/rails generate test_unit:model article
create  test/models/article_test.rb

# article_test.rb
require "test_helper"

class ArticleTest < ActiveSupport::TestCase
  # test "the truth" do
  #   assert true
  # end
end

$ bin/rails generate scaffold_controller article
...
create  app/controllers/articles_controller.rb
...
invoke  test_unit
create    test/controllers/articles_controller_test.rb
...

$ bin/rails generate test_unit:scaffold article
...
invoke  test_unit
create    test/controllers/articles_controller_test.rb
...

# articles_controller_test.rb
class ArticlesControllerTest < ActionDispatch::IntegrationTest
  test "should get index" do
    get articles_url
    assert_response :success
  end
end

get article_url(Article.first), headers: { "HTTP_REFERER" => "http://example.com/home" }

patch article_url(Article.last), params: { article: { title: "updated" } }, xhr: true

post articles_url, params: { article: { title: "Ahoy!" } }, as: :json

test "should create article" do
  assert_difference("Article.count") do
    post articles_url, params: { article: { body: "Rails is awesome!", title: "Hello Rails" } }
  end

  assert_redirected_to article_path(Article.last)
end

post articles_url, params: { article: { body: "Rails is awesome!", title: "Hello Rails" } }, headers: { Authorization: ActionController::HttpAuthentication::Basic.encode_credentials("dhh", "secret") }

test "AJAX request" do
  article = articles(:one)
  get article_url(article), xhr: true

  assert_equal "hello world", @response.body
  assert_equal "text/javascript", @response.media_type
end

flash["gordon"]               # or flash[:gordon]
session["shmession"]          # or session[:shmession]
cookies["are_good_for_u"]     # or cookies[:are_good_for_u]

class ArticlesControllerTest < ActionDispatch::IntegrationTest
  test "should get index" do
    get articles_url

    assert_equal "index", @controller.action_name
    assert_equal "application/x-www-form-urlencoded", @request.media_type
    assert_match "Articles", @response.body
  end
end

# setting an HTTP Header
get articles_url, headers: { "Content-Type": "text/plain" } # simulate the request with custom header

# setting a CGI variable
get articles_url, headers: { "HTTP_REFERER": "http://example.com/home" } # simulate the request with custom env variable

test "should create article" do
  assert_difference("Article.count") do
    post articles_url, params: { article: { title: "Some title" } }
  end

  assert_redirected_to article_path(Article.last)
  assert_equal "Article was successfully created.", flash[:notice]
end

$ bin/rails test test/controllers/articles_controller_test.rb -n test_should_create_article
Running 1 tests in a single process (parallelization threshold is 50)
Run options: -n test_should_create_article --seed 32266

# Running:

F

Finished in 0.114870s, 8.7055 runs/s, 34.8220 assertions/s.

  1) Failure:
ArticlesControllerTest#test_should_create_article [/test/controllers/articles_controller_test.rb:16]:
--- expected
+++ actual
@@ -1 +1 @@
-"Article was successfully created."
+nil

1 runs, 4 assertions, 1 failures, 0 errors, 0 skips

def create
  @article = Article.new(article_params)

  if @article.save
    flash[:notice] = "Article was successfully created."
    redirect_to @article
  else
    render "new"
  end
end

$ bin/rails test test/controllers/articles_controller_test.rb -n test_should_create_article
Running 1 tests in a single process (parallelization threshold is 50)
Run options: -n test_should_create_article --seed 18981

# Running:

.

Finished in 0.081972s, 12.1993 runs/s, 48.7972 assertions/s.

1 runs, 4 assertions, 0 failures, 0 errors, 0 skips

test "should show article" do
  article = articles(:one)
  get article_url(article)
  assert_response :success
end

test "should delete article" do
  article = articles(:one)
  assert_difference("Article.count", -1) do
    delete article_url(article)
  end

  assert_redirected_to articles_path
end

test "should update article" do
  article = articles(:one)

  patch article_url(article), params: { article: { title: "updated" } }

  assert_redirected_to article_path(article)
  # Reload article to refresh data and assert that title is updated.
  article.reload
  assert_equal "updated", article.title
end

require "test_helper"

class ArticlesControllerTest < ActionDispatch::IntegrationTest
  # called before every single test
  setup do
    @article = articles(:one)
  end

  # called after every single test
  teardown do
    # when controller is using cache it may be a good idea to reset it afterwards
    Rails.cache.clear
  end

  test "should show article" do
    # Reuse the @article instance variable from setup
    get article_url(@article)
    assert_response :success
  end

  test "should destroy article" do
    assert_difference("Article.count", -1) do
      delete article_url(@article)
    end

    assert_redirected_to articles_path
  end

  test "should update article" do
    patch article_url(@article), params: { article: { title: "updated" } }

    assert_redirected_to article_path(@article)
    # Reload association to fetch updated data and assert that title is updated.
    @article.reload
    assert_equal "updated", @article.title
  end
end

$ bin/rails generate integration_test user_flows
      invoke  test_unit
      create  test/integration/user_flows_test.rb

require "test_helper"

class UserFlowsTest < ActionDispatch::IntegrationTest
  # test "the truth" do
  #   assert true
  # end
end

$ bin/rails generate integration_test blog_flow

      invoke  test_unit
      create    test/integration/blog_flow_test.rb

require "test_helper"

class BlogFlowTest < ActionDispatch::IntegrationTest
  test "can see the welcome page" do
    get "/"
    assert_dom "h1", "Welcome#index"
  end
end

test "can create an article" do
  get "/articles/new"
  assert_response :success

  post "/articles",
    params: { article: { title: "can create", body: "article successfully." } }
  assert_response :redirect
  follow_redirect!
  assert_response :success
  assert_dom "p", "Title:\n  can create"
end

post "/articles",
  params: { article: { title: "can create", body: "article successfully." } }
assert_response :redirect
follow_redirect!

   $ bin/rails generate scaffold Article title:string body:text --system-tests=true

   $ bin/rails generate system_test articles

$ bin/rails generate system_test users
      invoke test_unit
      create test/system/users_test.rb

require "application_system_test_case"

class UsersTest < ApplicationSystemTestCase
  # test "visiting the index" do
  #   visit users_url
  #
  #   assert_dom "h1", text: "Users"
  # end
end

require "test_helper"
require "capybara/cuprite"

class ApplicationSystemTestCase < ActionDispatch::SystemTestCase
  driven_by :cuprite
end

require "test_helper"

class ApplicationSystemTestCase < ActionDispatch::SystemTestCase
  driven_by :selenium, using: :firefox
end

require "test_helper"

class ApplicationSystemTestCase < ActionDispatch::SystemTestCase
  driven_by :selenium, using: :headless_chrome
end

require "test_helper"

class ApplicationSystemTestCase < ActionDispatch::SystemTestCase
  url = ENV.fetch("SELENIUM_REMOTE_URL", nil)
  options = if url
    { browser: :remote, url: url }
  else
    { browser: :chrome }
  end
  driven_by :selenium, using: :headless_chrome, options: options
end

$ SELENIUM_REMOTE_URL=https://:4444/wd/hub bin/rails test:system

require "test_helper"

class ApplicationSystemTestCase < ActionDispatch::SystemTestCase
  setup do
      Capybara.server_host = "0.0.0.0" # bind to all interfaces
      Capybara.app_host = "http://#{IPSocket.getaddress(Socket.gethostname)}" if ENV["SELENIUM_REMOTE_URL"].present?
    end
  # ...
end

$ bin/rails generate system_test articles

      invoke  test_unit
      create    test/system/articles_test.rb

require "application_system_test_case"

class ArticlesTest < ApplicationSystemTestCase
  test "viewing the index" do
    visit articles_path
    assert_selector "h1", text: "Articles"
  end
end

$ bin/rails test:system

test "should create Article" do
  visit articles_path

  click_on "New Article"

  fill_in "Title", with: "Creating an Article"
  fill_in "Body", with: "Created this article successfully!"

  click_on "Create Article"

  assert_text "Creating an Article"
end

require "test_helper"

class MobileSystemTestCase < ActionDispatch::SystemTestCase
  driven_by :selenium, using: :chrome, screen_size: [375, 667]
end

require "mobile_system_test_case"

class PostsTest < MobileSystemTestCase
  test "visiting the index" do
    visit posts_url
    assert_selector "h1", text: "Posts"
  end
end

# test/test_helper.rb

module SignInHelper
  def sign_in_as(user)
    post sign_in_url(email: user.email, password: user.password)
  end
end

class ActionDispatch::IntegrationTest
  include SignInHelper
end

require "test_helper"

class ProfileControllerTest < ActionDispatch::IntegrationTest
  test "should show profile" do
    # helper is now reusable from any controller test case
    sign_in_as users(:david)

    get profile_url
    assert_response :success
  end
end

# test/test_helpers/multiple_assertions.rb
module MultipleAssertions
  def assert_multiple_of_forty_two(number)
    assert (number % 42 == 0), "expected #{number} to be a multiple of 42"
  end
end

require "test_helper"
require "test_helpers/multiple_assertions"

class NumberTest < ActiveSupport::TestCase
  include MultipleAssertions

  test "420 is a multiple of 42" do
    assert_multiple_of_forty_two 420
  end
end

# test/test_helper.rb
require "test_helpers/sign_in_helper"

class ActionDispatch::IntegrationTest
  include SignInHelper
end

# test/test_helper.rb
Dir[Rails.root.join("test", "test_helpers", "**", "*.rb")].each { |file| require file }

assert_dom "title", "Welcome to the Rails Testing Guide"

assert_dom "ul.navigation" do
  assert_dom "li.menu_item"
end

assert_dom "ol" do |elements|
  elements.each do |element|
    assert_dom element, "li", 4
  end
end

assert_dom "ol" do
  assert_dom "li", 8
end

assert_dom_equal '<a href="http://www.further-reading.com">Read more</a>',
  link_to("Read more", "http://www.further-reading.com")

test "renders a link to itself" do
  article = Article.create! title: "Hello, world"

  render "articles/article", article: article
  anchor = document_root_element.at("a")

  assert_equal article.name, anchor.text
  assert_equal article_url(article), anchor["href"]
end

test "renders a link to itself" do
  article = Article.create! title: "Hello, world"

  render "articles/article", article: article
  anchor = document_root_element.at("a")
  url = article_url(article)

  assert_pattern do
    anchor => { content: "Hello, world", attributes: [{ name: "href", value: url }] }
  end
end

# test/view_partial_test_case.rb

require "test_helper"
require "capybara/minitest"

class ViewPartialTestCase < ActionView::TestCase
  include Capybara::Minitest::Assertions

  def page
    Capybara.string(rendered)
  end
end

# test/views/article_partial_test.rb

require "view_partial_test_case"

class ArticlePartialTest < ViewPartialTestCase
  test "renders a link to itself" do
    article = Article.create! title: "Hello, world"

    render "articles/article", article: article

    assert_link article.title, href: article_url(article)
  end
end

register_parser :rss, -> rendered { RSS::Parser.parse(rendered) }

test "renders RSS" do
  article = Article.create!(title: "Hello, world")

  render formats: :rss, partial: article

  assert_equal "Hello, world", rendered.rss.items.last.title
end

test "renders HTML" do
  article = Article.create!(title: "Hello, world")

  render partial: "articles/article", locals: { article: article }

  assert_pattern { rendered.html.at("main h1") => { content: "Hello, world" } }
end

test "renders JSON" do
  article = Article.create!(title: "Hello, world")

  render formats: :json, partial: "articles/article", locals: { article: article }

  assert_pattern { rendered.json => { title: "Hello, world" } }
end

assert_dom_email do
  assert_dom "small", "Please click the 'Unsubscribe' link if you want to opt-out."
end

class ArticlePartialTest < ActionView::TestCase
  test "renders a link to itself" do
    article = Article.create! title: "Hello, world"

    render "articles/article", article: article

    assert_includes rendered, article.title
  end
end

test "renders a link to itself" do
  article = Article.create! title: "Hello, world"

  render "articles/article", article: article

  assert_dom "a[href=?]", article_url(article), text: article.title
end

module UsersHelper
  def link_to_user(user)
    link_to "#{user.first_name} #{user.last_name}", user
  end
end

class UsersHelperTest < ActionView::TestCase
  test "should return the user's full name" do
    user = users(:david)

    assert_dom_equal %{<a href="/user/#{user.id}">David Heinemeier Hansson</a>}, link_to_user(user)
  end
end

require "test_helper"

class UserMailerTest < ActionMailer::TestCase
  test "invite" do
    # Create the email and store it for further assertions
    email = UserMailer.create_invite("me@example.com",
                                     "friend@example.com", Time.now)

    # Send the email, then test that it got queued
    assert_emails 1 do
      email.deliver_now
    end

    # Test the body of the sent email contains what we expect it to
    assert_equal ["me@example.com"], email.from
    assert_equal ["friend@example.com"], email.to
    assert_equal "You have been invited by me@example.com", email.subject
    assert_equal read_fixture("invite").join, email.body.to_s
  end
end

Hi friend@example.com,

You have been invited.

Cheers!

require "test_helper"

class UserMailerTest < ActionMailer::TestCase
  test "invite" do
    # Create the email and store it for further assertions
    email = UserMailer.create_invite("me@example.com", "friend@example.com")

    # Test that the email got enqueued with the correct arguments
    assert_enqueued_email_with UserMailer, :create_invite, args: ["me@example.com", "friend@example.com"] do
      email.deliver_later
    end
  end
end

require "test_helper"

class UserMailerTest < ActionMailer::TestCase
  test "invite" do
    # Create the email and store it for further assertions
    email = UserMailer.create_invite(from: "me@example.com", to: "friend@example.com")

    # Test that the email got enqueued with the correct named arguments
    assert_enqueued_email_with UserMailer, :create_invite,
    args: [{ from: "me@example.com", to: "friend@example.com" }] do
      email.deliver_later
    end
  end
end

require "test_helper"

class UserMailerTest < ActionMailer::TestCase
  test "invite" do
    # Create the email and store it for further assertions
    email = UserMailer.with(all: "good").create_invite("me@example.com", "friend@example.com")

    # Test that the email got enqueued with the correct mailer parameters and arguments
    assert_enqueued_email_with UserMailer, :create_invite,
    params: { all: "good" }, args: ["me@example.com", "friend@example.com"] do
      email.deliver_later
    end
  end
end

require "test_helper"

class UserMailerTest < ActionMailer::TestCase
  test "invite" do
    # Create the email and store it for further assertions
    email = UserMailer.with(to: "friend@example.com").create_invite

    # Test that the email got enqueued with the correct mailer parameters
    assert_enqueued_email_with UserMailer.with(to: "friend@example.com"), :create_invite do
      email.deliver_later
    end
  end
end

# Integration Test
require "test_helper"

class UsersControllerTest < ActionDispatch::IntegrationTest
  test "invite friend" do
    # Asserts the difference in the ActionMailer::Base.deliveries
    assert_emails 1 do
      post invite_friend_url, params: { email: "friend@example.com" }
    end
  end
end

# System Test
require "test_helper"

class UsersTest < ActionDispatch::SystemTestCase
  driven_by :selenium, using: :headless_chrome

  test "inviting a friend" do
    visit invite_users_url
    fill_in "Email", with: "friend@example.com"
    assert_emails 1 do
      click_on "Invite"
    end
  end
end

require "test_helper"

class BillingJobTest < ActiveJob::TestCase
  test "account is charged" do
    perform_enqueued_jobs do
      BillingJob.perform_later(account, product)
    end
    assert account.reload.charged_for?(product)
  end
end

require "test_helper"

class AccountTest < ActiveSupport::TestCase
  include ActiveJob::TestHelper

  test "#charge_for enqueues billing job" do
    assert_enqueued_with(job: BillingJob) do
      account.charge_for(product)
    end

    assert_not account.reload.charged_for?(product)

    perform_enqueued_jobs

    assert account.reload.charged_for?(product)
  end
end

require "test_helper"

class BillingJobTest < ActiveJob::TestCase
  test "does not charge accounts with insufficient funds" do
    assert_raises(InsufficientFundsError) do
      BillingJob.new(empty_account, product).perform
    end
    assert_not account.reload.charged_for?(product)
  end
end

class ApplicationCable::ConnectionTest < ActionCable::Connection::TestCase
  test "connects with params" do
    # Simulate a connection opening by calling the `connect` method
    connect params: { user_id: 42 }

    # You can access the Connection object via `connection` in tests
    assert_equal connection.user_id, "42"
  end

  test "rejects connection without params" do
    # Use `assert_reject_connection` matcher to verify that
    # connection is rejected
    assert_reject_connection { connect }
  end
end

test "connects with cookies" do
  cookies.signed[:user_id] = "42"

  connect

  assert_equal connection.user_id, "42"
end

require "test_helper"

class ChatChannelTest < ActionCable::Channel::TestCase
  test "subscribes and stream for room" do
    # Simulate a subscription creation by calling `subscribe`
    subscribe room: "15"

    # You can access the Channel object via `subscription` in tests
    assert subscription.confirmed?
    assert_has_stream "chat_15"
  end
end

require "test_helper"

class WebNotificationsChannelTest < ActionCable::Channel::TestCase
  test "subscribes and stream for user" do
    stub_connection current_user: users(:john)

    subscribe

    assert_has_stream_for users(:john)
  end
end

require "test_helper"

class ProductTest < ActionCable::TestCase
  test "broadcast status after charge" do
    assert_broadcast_on("products:#{product.id}", type: "charged") do
      product.charge(account)
    end
  end
end

# app/jobs/chat_relay_job.rb
class ChatRelayJob < ApplicationJob
  def perform(room, message)
    ChatChannel.broadcast_to room, text: message
  end
end

# test/jobs/chat_relay_job_test.rb
require "test_helper"

class ChatRelayJobTest < ActiveJob::TestCase
  include ActionCable::TestHelper

  test "broadcast message to room" do
    room = rooms(:all)

    assert_broadcast_on(ChatChannel.broadcasting_for(room), text: "Hi!") do
      ChatRelayJob.perform_now(room, "Hi!")
    end
  end
end

$ bin/rails test

class ActiveSupport::TestCase
  parallelize(workers: 2)
end

$ PARALLEL_WORKERS=15 bin/rails test

class ActiveSupport::TestCase
  parallelize_setup do |worker|
    # setup databases
  end

  parallelize_teardown do |worker|
    # cleanup databases
  end

  parallelize(workers: :number_of_processors)
end

class ActiveSupport::TestCase
  parallelize(workers: :number_of_processors, with: :threads)
end

class WorkerTest < ActiveSupport::TestCase
  self.use_transactional_tests = false

  test "parallel transactions" do
    # start some threads that create transactions
  end
end

config.active_support.test_parallelization_threshold = 100

class ActiveSupport::TestCase
  parallelize threshold: 100
end

# config/environments/test.rb
config.eager_load = ENV["CI"].present?

require "test_helper"

class ZeitwerkComplianceTest < ActiveSupport::TestCase
  test "eager loads all files without errors" do
    assert_nothing_raised { Rails.application.eager_load! }
  end
end

# Given a user is eligible for gifting a month after they register.
user = User.create(name: "Gaurish", activation_date: Date.new(2004, 10, 24))
assert_not user.applicable_for_gifting?

travel_to Date.new(2004, 11, 24) do
  # Inside the `travel_to` block `Date.current` is stubbed
  assert_equal Date.new(2004, 10, 24), user.activation_date
  assert user.applicable_for_gifting?
end

# The change was visible only inside the `travel_to` block.
assert_equal Date.new(2004, 10, 24), user.activation_date