Refactor mailer tests

app/services/data_exports/csv/invoice_fees.rb

@@ -54,7 +54,7 @@ def serialized_item(fee)
 
         serialized_subscription = {
           external_id: fee.subscription&.external_id,
-          plan_code: fee.subscription&.plan&.code,
+          plan_code: fee.subscription&.plan&.code
         }
 
         [

spec/mailers/data_export_mailer_spec.rb

@@ -3,48 +3,64 @@
 require 'rails_helper'
 
 RSpec.describe DataExportMailer, type: :mailer do
-  subject(:data_export_mailer) { described_class }
-
   let(:data_export) { create(:data_export, :completed) }
 
   describe '#completed' do
-    let(:mailer) { data_export_mailer.with(data_export:).completed }
+    let(:mail) { described_class.with(data_export:).completed }
     let(:file_url) { "https://api.lago.dev/rails/active_storage/blobs/redirect/eyJf" }
 
-    before do
-      allow(data_export).to receive(:file_url).and_return(file_url)
+    before { allow(data_export).to receive(:file_url).and_return(file_url) }
+
+    describe 'subject' do
+      subject { mail.subject }
+
+      context 'with invoice data export' do
+        let(:data_export) { create(:data_export, :completed, resource_type: 'invoices') }
+
+        it { is_expected.to eq 'Your Lago invoices export is ready!' }
+      end
+
+      context 'with invoice fee data export' do
+        let(:data_export) { create(:data_export, :completed, resource_type: 'invoice_fees') }
+
+        it { is_expected.to eq 'Your Lago invoice fees export is ready!' }
+      end
     end
 
-    specify do
-      expect(mailer.to).to eq([data_export.user.email])
-      expect(mailer.subject).to eq("Your Lago invoices export is ready!")
-      expect(mailer.body.encoded).to match("Your invoices export is ready!")
-      expect(mailer.body.encoded).to match("will be available for 7 days")
-      expect(mailer.body.encoded).to match(data_export.file_url)
+    describe 'recipients' do
+      subject { mail.to }
+
+      it { is_expected.to eq [data_export.user.email] }
     end
 
-    context "when the resource type is invoice_fees" do
-      let(:data_export) { create(:data_export, :completed, resource_type: 'invoice_fees') }
+    describe 'body' do
+      subject { mail.body.to_s }
 
-      specify do
-        expect(mailer.subject).to eq("Your Lago invoice fees export is ready!")
-        expect(mailer.body.encoded).to match("Your invoice fees export is ready!")
+      it 'includes expiration notice and link to file', :aggregate_failures do
+        expect(subject).to match('will be available for 7 days')
+        expect(subject).to match(data_export.file_url)
       end
     end
 
-    context 'when data export is expired' do
-      let(:data_export) { create(:data_export, :expired) }
+    describe 'delivery' do
+      subject { mail.deliver_now }
 
-      it 'returns a mailer with nil values' do
-        expect(mailer.to).to be_nil
+      let(:deliveries) { ActionMailer::Base.deliveries }
+
+      context 'when data export is not completed' do
+        let(:data_export) { create(:data_export, :processing) }
+
+        it 'is not performed' do
+          expect { subject }.not_to change(deliveries, :count)
+        end
       end
-    end
 
-    context 'when data export is not completed' do
-      let(:data_export) { create(:data_export, :processing) }
+      context 'when data export is completed' do
+        let(:data_export) { create(:data_export, :completed) }
 
-      it 'returns a mailer with nil values' do
-        expect(mailer.to).to be_nil
+        it 'is performed' do
+          expect { subject }.to change(deliveries, :count).by(1)
+        end
       end
     end
   end