Add some basic tests for the email changed notification

test/mailers/email_changed_test.rb

@@ -0,0 +1,90 @@
+require 'test_helper'
+
+class EmailChangedTest < ActionMailer::TestCase
+  def setup
+    setup_mailer
+    Devise.mailer = 'Devise::Mailer'
+    Devise.mailer_sender = 'test@example.com'
+    Devise.send_email_changed_notification = true
+  end
+
+  def teardown
+    Devise.mailer = 'Devise::Mailer'
+    Devise.mailer_sender = 'please-change-me@config-initializers-devise.com'
+    Devise.send_email_changed_notification = false
+  end
+
+  def user
+    @user ||= create_user.tap { |u|
+      @original_user_email = u.email
+      u.update_attributes!(email: 'new-email@example.com')
+    }
+  end
+
+  def mail
+    @mail ||= begin
+      user
+      ActionMailer::Base.deliveries.last
+    end
+  end
+
+  test 'email sent after changing the user email' do
+    assert_not_nil mail
+  end
+
+  test 'content type should be set to html' do
+    assert mail.content_type.include?('text/html')
+  end
+
+  test 'send email changed to the original user email' do
+    mail
+    assert_equal [@original_user_email], mail.to
+  end
+
+  test 'set up sender from configuration' do
+    assert_equal ['test@example.com'], mail.from
+  end
+
+  test 'set up sender from custom mailer defaults' do
+    Devise.mailer = 'Users::Mailer'
+    assert_equal ['custom@example.com'], mail.from
+  end
+
+  test 'set up sender from custom mailer defaults with proc' do
+    Devise.mailer = 'Users::FromProcMailer'
+    assert_equal ['custom@example.com'], mail.from
+  end
+
+  test 'custom mailer renders parent mailer template' do
+    Devise.mailer = 'Users::Mailer'
+    assert_present mail.body.encoded
+  end
+
+  test 'set up reply to as copy from sender' do
+    assert_equal ['test@example.com'], mail.reply_to
+  end
+
+  test 'set up reply to as different if set in defaults' do
+    Devise.mailer = 'Users::ReplyToMailer'
+    assert_equal ['custom@example.com'], mail.from
+    assert_equal ['custom_reply_to@example.com'], mail.reply_to
+  end
+
+  test 'set up subject from I18n' do
+    store_translations :en, devise: { mailer: { email_changed: { subject: 'Email Has Changed' } } } do
+      assert_equal 'Email Has Changed', mail.subject
+    end
+  end
+
+  test 'subject namespaced by model' do
+    store_translations :en, devise: { mailer: { email_changed: { user_subject: 'User Email Has Changed' } } } do
+      assert_equal 'User Email Has Changed', mail.subject
+    end
+  end
+
+  test 'body should have user info' do
+    body = mail.body.encoded
+    assert_match @original_user_email, body
+    assert_match user.email, body
+  end
+end