Add scheduled email feature for reminders

spec/features/password_reset_spec.rb

@@ -0,0 +1,13 @@
+require 'rails_helper'
+
+RSpec.describe "ResetPassword", type: :feature do
+  it "sends an email upon a password reset request" do
+    user = create(:user)
+    visit new_user_session_path
+    click_link 'password'
+    fill_in 'Email', with: user.email
+    click_button 'reset password'
+    expect(page).to have_content 'You will receive an email with instructions on how to reset your password in a few minutes.'
+    expect(last_email).to have_content user.email
+  end
+end

spec/mailers/previews/reminder_mailer_preview.rb

@@ -0,0 +1,7 @@
+# Preview all emails at http://localhost:3000/rails/mailers/reminder_mailer
+class ReminderMailerPreview < ActionMailer::Preview
+  # Preview this email at http://localhost:3000/rails/mailers/reminder_mailer/schedule_email
+  def schedule_email
+    ReminderMailer.schedule_email(FactoryBot.build(:reminder), 'to@example.com')
+  end
+end

spec/mailers/reminder_mailer_spec.rb

@@ -0,0 +1,29 @@
+require 'rails_helper'
+
+RSpec.describe ReminderMailer, type: :mailer do
+  describe 'Email delivery' do
+    let(:reminder) { build :reminder }
+    let(:mail) { ReminderMailer.schedule_email reminder, 'to@example.org' }
+
+    it 'renders the headers' do
+      expect(mail.subject).to eq 'Reminder'
+      expect(mail.to).to eq ['to@example.org']
+      expect(mail.from).to eq ['from@example.com']
+    end
+
+    it 'renders the body' do
+      expect(mail.body.encoded).to have_content reminder.title
+      expect(mail.body.encoded).to have_content reminder.body
+    end
+  end
+
+  describe 'Scheduled email' do
+    before { clear_enqueued_jobs }
+    let(:reminder) { create :reminder }
+
+    it 'queues the reminder' do
+      expect { ReminderMailer.schedule_email(reminder, 'to@example.org').deliver_later(wait_until: reminder.date) }.to have_enqueued_job.on_queue('mailers')
+      expect { ReminderMailer.schedule_email(reminder, 'to@example.org').deliver_later(wait_until: reminder.date) }.to have_enqueued_job.at(reminder.date)
+    end
+  end
+end

spec/rails_helper.rb

@@ -35,7 +35,7 @@ rescue ActiveRecord::PendingMigrationError => e
 end
 RSpec.configure do |config|
   # Remove this line if you're not using ActiveRecord or ActiveRecord fixtures
-  config.fixture_path = "#{::Rails.root}/spec/fixtures"
+  # config.fixture_path = "#{::Rails.root}/spec/fixtures"
 
   # If you're not using ActiveRecord, or you'd prefer not to run each of your
   # examples within a transaction, remove the following line or assign false
@@ -63,5 +63,7 @@ RSpec.configure do |config|
   # config.filter_gems_from_backtrace("gem name")
 
   config.include FactoryBot::Syntax::Methods
+  config.include(MailerMacros)
+  config.before(:each) { reset_email }
   config.include Devise::Test::IntegrationHelpers, type: :request
 end

spec/support/mailer_macros.rb

@@ -0,0 +1,9 @@
+module MailerMacros
+  def last_email
+    ActionMailer::Base.deliveries.last
+  end
+
+  def reset_email
+    ActionMailer::Base.deliveries = []
+  end
+end