Send email confirmation when BTC payment is confirmed

spec/jobs/btcpay_check_donation_job_spec.rb

@@ -6,12 +6,20 @@ RSpec.describe BtcpayCheckDonationJob, type: :job do
 
   let(:donation) do
     user.donations.create!(
-      donation_method: "btcpay", btcpay_invoice_id: "K4e31MhbLKmr3D7qoNYRd3",
+      donation_method: "btcpay",
+      btcpay_invoice_id: "K4e31MhbLKmr3D7qoNYRd3",
       paid_at: nil, payment_status: "processing",
       fiat_amount: 120, fiat_currency: "USD"
     )
   end
 
+  before do
+    allow_any_instance_of(User).to receive(:ldap_entry).and_return({
+      uid: user.cn, ou: user.ou, mail: user.email, admin: nil,
+      display_name: nil
+    })
+  end
+
   after(:each) do
     clear_enqueued_jobs
     clear_performed_jobs
@@ -48,16 +56,24 @@ RSpec.describe BtcpayCheckDonationJob, type: :job do
     end
 
     it "updates the donation record" do
-      perform_enqueued_jobs { job }
-
+      perform_enqueued_jobs(only: described_class) { job }
       donation.reload
       expect(donation.paid_at).not_to be_nil
       expect(donation.payment_status).to eq("settled")
     end
 
+    it "notifies the user via email" do
+      perform_enqueued_jobs(only: described_class) { job }
+      expect(enqueued_jobs.size).to eq(1)
+      job = enqueued_jobs.select{|j| j['job_class'] == "ActionMailer::MailDeliveryJob"}.first
+      expect(job['arguments'][0]).to eq('NotificationMailer')
+      expect(job['arguments'][1]).to eq('bitcoin_donation_confirmed')
+      expect(job['arguments'][3]['params']['user']['_aj_globalid']).to eq('gid://akkounts/User/1')
+    end
+
     it "does not enqueue itself again" do
       expect_any_instance_of(described_class).not_to receive(:re_enqueue_job)
-      perform_enqueued_jobs { job }
+      perform_enqueued_jobs(only: described_class) { job }
     end
   end
 end