AO3-7034: Create signup_notification mailer preview

app/mailers/user_mailer.rb

@@ -221,7 +221,7 @@ def signup_notification(user_id)
     I18n.with_locale(@user.preference.locale_for_mails) do
       mail(
         to: @user.email,
-        subject: t("user_mailer.signup_notification.subject", app_name: ArchiveConfig.APP_SHORT_NAME)
+        subject: default_i18n_subject(app_name: ArchiveConfig.APP_SHORT_NAME)
       )
     end
   end

app/views/user_mailer/signup_notification.html.erb

@@ -1,12 +1,12 @@
 <% content_for :message do %>
-<p><%= t('.welcome',
-           login: style_bold(@user.login)).html_safe %></p>
-<p><%= t('.activate.html',
-           activate_account_link: style_link(t('.activate_your_account'), activate_url(id: @user.confirmation_token))) %></p>
-<p><%= t('.features.html') %></p>
-<p><%= t('.information.html',
-           faq_link: style_link(t('.faq'), archive_faqs_url),
-           admin_posts_link: style_link(t('.admin_posts'), admin_posts_url),
-           contact_support_link: support_link(t '.contact_support')) %></p>
-<p><%= t('.bye') %></p>
+<p><%= t(".welcome.html",
+         login: style_bold(@user.login)) %></p>
+<p><%= t(".activate.html",
+         activate_account_link: style_link(t(".activate_your_account"), activate_url(id: @user.confirmation_token))) %></p>
+<p><%= t(".features.html") %></p>
+<p><%= t(".information.html",
+         faq_link: style_link(t(".faq"), archive_faqs_url),
+         admin_posts_link: style_link(t(".admin_posts"), admin_posts_url),
+         contact_support_link: support_link(t(".contact_support"))) %></p>
+<p><%= t(".bye") %></p>
 <% end %>

app/views/user_mailer/signup_notification.text.erb

@@ -1,16 +1,16 @@
 <% content_for :message do %>
-<%= t('.welcome',
+<%= t(".welcome.text",
            login: @user.login) %>
 
-<%= t('.activate.text',
+<%= t(".activate.text",
            activate_account_url: activate_url(id: @user.confirmation_token)) %>
 
-<%= t('.features.text') %>
+<%= t(".features.text") %>
 
-<%= t('.information.text',
+<%= t(".information.text",
            faq_url: archive_faqs_url,
            admin_posts_url: admin_posts_url, 
            contact_support_url: new_feedback_report_url) %>
 
-<%= t('.bye') %>
+<%= t(".bye") %>
 <% end %>

config/locales/mailers/en.yml

@@ -817,7 +817,9 @@ en:
         html: There's lots of information and advice on how to use the Archive in our %{faq_link}. You'll find the latest news about site developments on %{admin_posts_link}. If you need more help, run into a bug, or have questions or comments, please %{contact_support_link}, who are always happy to help out.
         text: 'There''s lots of information and advice on how to use the Archive in our FAQ at %{faq_url}. You''ll find the latest news about site developments on AO3 News at %{admin_posts_url}. If you need more help, run into a bug, or have questions or comments, please contact Support, who are always happy to help out: %{contact_support_url}.'
       subject: "[%{app_name}] Activate your account"
-      welcome: Welcome to the Archive of Our Own, %{login}!
+      welcome:
+        html: Welcome to the Archive of Our Own, %{login}!
+        text: Welcome to the Archive of Our Own, %{login}!
   users:
     mailer:
       confirmation_instructions:

test/mailers/previews/user_mailer_preview.rb

@@ -473,6 +473,12 @@ def related_work_notification_anon
     UserMailer.related_work_notification(user.id, related_work.id)
   end
 
+  # URL: /rails/mailers/user_mailer/signup_notification
+  def signup_notification
+    user = create(:user, :for_mailer_preview, confirmed_at: nil)
+    UserMailer.signup_notification(user.id)
+  end
+
   private
 
   def creatorship_notification_data(creation_type)