Add simple send integration tests

Dockerfile

@@ -54,6 +54,7 @@ RUN bundle install
 # Copy over intergration test files
 COPY test/mailers/ test/mailers/
 COPY test/system/ test/system/
+COPY test/integration test/integration
 COPY test/application_system_test_case.rb /test/application_system_test_case.rb
 COPY test/app/mailers/ app/mailers/
 COPY test/app/views/ app/views/

test/integration/notify_mailer_sending_test.rb

@@ -0,0 +1,36 @@
+require "test_helper"
+
+class NotifyMailerSendingTest < ActionDispatch::IntegrationTest
+  # these tests are designed to run in our integration environment and make real
+  # requests to Notify, the API key we use WILL NOT actually send any email.
+  #
+  # Once this spec runs, you will see these email in the Notify 'API Integrations'
+  # log which requires an login for our integration test Notify account and only
+  # remain for 7 days.
+  #
+  test "can send a template email" do
+    result = NotifyMailer.with(
+      to: "template.email@notifications.service.gov.uk"
+    ).template_email.deliver_now
+
+    assert result.instance_of? Mail::Message
+  end
+
+  test "can send a template email with personalisation" do
+    result = NotifyMailer.with(
+      to: "template.email@notifications.service.gov.uk",
+      name: "Test Name"
+    ).template_with_personalisation.deliver_now
+
+    assert result.instance_of? Mail::Message
+  end
+
+  test "can send a view email" do
+    result = NotifyMailer.with(
+      to: "view.email@notifications.service.gov.uk",
+      subject: "View email subject"
+    ).view_email.deliver_now
+
+    assert result.instance_of? Mail::Message
+  end
+end