Railsチュートリアルの11章のテストにパスしない

Question

前提・実現したいこと

Railsチュートリアルの第11章の11.2.3のタスクである「送信メールのテスト」に取り組んでいるのですが、テストにパスしません。お時間がありましたら、アドバイスをお願いいたします。

エラーメッセージ

ec2-user:~/environment/sample_app (account-activation) $ rails test:mailers
Started with run options --seed 36811

ERROR["test_account_activation", UserMailerTest, 0.3552794820006966]
 test_account_activation#UserMailerTest (0.36s)
ActionView::Template::Error:         ActionView::Template::Error: Missing host to link to! Please provide the :host parameter, set default_url_options[:host], or set :only_path to true
            app/views/user_mailer/account_activation.html.erb:9:in `_app_views_user_mailer_account_activation_html_erb___3881546861189490321_45800140'
            app/mailers/user_mailer.rb:5:in `account_activation'
            test/mailers/user_mailer_test.rb:8:in `block in <class:UserMailerTest>'

  1/1: [===============================================================================================================================] 100% Time: 00:00:00, Time: 00:00:00

Finished in 0.35870s
1 tests, 0 assertions, 0 failures, 1 errors, 0 skips

app/views/user_mailer/account_activation.htmlのコード

<h1>Sample App</h1>

<p>Hi <%= @user.name %>,</p>

<p>
Welcome to the Sample App! Click on the link below to activate your account:
</p>

<%= link_to "Activate", edit_account_activation_url(@user.activation_token,
                                                    email: @user.email) %>

app/mailers/user_mailer.rbのコード

class UserMailer < ApplicationMailer

  def account_activation(user)
    @user = user
    mail to: user.email, subject: "Account activation"
  end

  def password_reset
    @greeting = "Hi"

    mail to: "[e-mail]"
  end
end

test/mailers/user_mailer_test.rbのコード

require 'test_helper'

class UserMailerTest < ActionMailer::TestCase
  test "account_activation" do
    user = users(:michael)
    user.activation_token = User.new_token
    mail = UserMailer.account_activation(user)
    assert_equal "Account activation", mail.subject
    assert_equal [user.email], mail.to
    assert_equal ["[e-mail]"], mail.from
    assert_match user.name,               mail.body.encoded
    assert_match user.activation_token,   mail.body.encoded
    assert_match CGI.escape(user.email),  mail.body.encoded
  end
end

関連ファイルのコードも一応載せておきます。

config/environments/test.rbのコード
下記のコードが　app/mailers/application_mailer.rb　のものになっていたため、修正いたしました。

Rails.application.configure do
  # Settings specified here will take precedence over those in config/application.rb.

  # The test environment is used exclusively to run your application's
  # test suite. You never need to work with it otherwise. Remember that
  # your test database is "scratch space" for the test suite and is wiped
  # and recreated between test runs. Don't rely on the data there!
  config.cache_classes = true

  # Do not eager load code on boot. This avoids loading your whole application
  # just for the purpose of running a single test. If you are using a tool that
  # preloads Rails for running tests, you may have to set it to true.
  config.eager_load = false

  # Configure public file server for tests with Cache-Control for performance.
  config.public_file_server.enabled = true
  config.public_file_server.headers = {
    'Cache-Control' => "public, max-age=#{1.hour.seconds.to_i}"
  }

  # Show full error reports and disable caching.
  config.consider_all_requests_local       = true
  config.action_controller.perform_caching = false

  # Raise exceptions instead of rendering exception templates.
  config.action_dispatch.show_exceptions = false

  # Disable request forgery protection in test environment.
  config.action_controller.allow_forgery_protection = false
  config.action_mailer.perform_caching = false

  # Tell Action Mailer not to deliver emails to the real world.
  # The :test delivery method accumulates sent emails in the
  # ActionMailer::Base.deliveries array.
  config.action_mailer.delivery_method = :test
  

  # Print deprecation notices to the stderr.
  config.active_support.deprecation = :stderr

  # Raises error for missing translations
  # config.action_view.raise_on_missing_translations = true
end

test/mailers/previews/user_mailer_preview.rbのコード

# Preview all emails at http://localhost:3000/rails/mailers/user_mailer
class UserMailerPreview < ActionMailer::Preview

  # Preview this email at http://localhost:3000/rails/mailers/user_mailer/account_activation
  def account_activation
    user = User.first
    user.activation_token = User.new_token
    UserMailer.account_activation(user)
  end

  # Preview this email at http://localhost:3000/rails/mailers/user_mailer/password_reset
  def password_reset
    UserMailer.password_reset
  end

end

app/mailers/application_mailer.rbのコード

class ApplicationMailer < ActionMailer::Base
  default from: "[e-mail]"
  layout 'mailer'
end

追加のコードです
config/environments/development.rb　のコード

Rails.application.configure do
  # Settings specified here will take precedence over those in config/application.rb.

  # In the development environment your application's code is reloaded on
  # every request. This slows down response time but is perfect for development
  # since you don't have to restart the web server when you make code changes.
  config.cache_classes = false

  # Do not eager load code on boot.
  config.eager_load = false

  # Show full error reports.
  config.consider_all_requests_local = true

  # Enable/disable caching. By default caching is disabled.
  if Rails.root.join('tmp/caching-dev.txt').exist?
    config.action_controller.perform_caching = true

    config.cache_store = :memory_store
    config.public_file_server.headers = {
      'Cache-Control' => "public, max-age=#{2.days.seconds.to_i}"
    }
  else
    config.action_controller.perform_caching = false

    config.cache_store = :null_store
  end

  # Don't care if the mailer can't send.
  config.action_mailer.raise_delivery_errors = true
  config.action_mailer.delivery_method = :test
  config.action_mailer.default_url_options = { host: 'example.com' }

  config.action_mailer.perform_caching = false

  # Print deprecation notices to the Rails logger.
  config.active_support.deprecation = :log

  # Raise an error on page load if there are pending migrations.
  config.active_record.migration_error = :page_load

  # Debug mode disables concatenation and preprocessing of assets.
  # This option may cause significant delays in view rendering with a large
  # number of complex assets.
  config.assets.debug = true

  # Suppress logger output for asset requests.
  config.assets.quiet = true

  # Raises error for missing translations
  # config.action_view.raise_on_missing_translations = true

  # Use an evented file watcher to asynchronously detect changes in source code,
  # routes, locales, etc. This feature depends on the listen gem.
  config.file_watcher = ActiveSupport::EventedFileUpdateChecker
end

試したこと

エラーメッセージに書かれていたすべてのファイルを確認して、一応コピペしたのですがパスしませんでした。

補足情報（FW/ツールのバージョンなど）

Answer 1

Missing host to link to! Please provide the :host parameter, set default_url_options[:host],
とあります。　メールに貼る link先の host部がないのでエラーに成っています。

config/environments/test.rb の中で
class ApplicationMailer < ActionMailer::Base
して設定した経験がないのですが、
Rails.application.configure do　でやるなら
｀config.action_mailer.default_url_options =
{ host: 'www.example.com' }`
とやります。
testで実際にはメールを出さないのでしょうから何でも良いのではと

Comments

[iseita]

回答していただきありがとうございました！
質問の中のコードが間違っていたために、ややこしくなってしまい申し訳ありませんでした。
ご指摘していただいたことで間違いに気づくことができました。

Answer 2

原因は
私がconfig/environments/development.rb と　config/environments/test.rb 混同していたことにありました。

①　config/environments/development.rb　のコードの中の下記の部分を修正しました。

（修正前）
config.action_mailer.raise_delivery_errors = true
config.action_mailer.delivery_method = :test
config.action_mailer.default_url_options = { host: 'example.com' }

⇓

（修正後）
config.action_mailer.raise_delivery_errors = true
config.action_mailer.delivery_method = :test
host = 'rails-tutorial-mhartl.c9users.io' # クラウドIDE
config.action_mailer.default_url_options = { host: host, protocol: 'https' }

②　config/environments/test.rb のコードの中の下記の部分を修正しました。

（修正前）

　config.action_mailer.delivery_method = :test

⇓

（修正後）
config.action_mailer.delivery_method = :test
config.action_mailer.default_url_options = { host: 'example.com' }

※　最後の　config.action_mailer.default_url_options = { host: 'example.com' }　を追加しました。

無事テストをパスできました！