Add coverage for misc serializers (#32781)

spec/serializers/rest/admin/account_serializer_spec.rb

@@ -0,0 +1,25 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+RSpec.describe REST::Admin::AccountSerializer do
+  subject { serialized_record_json(record, described_class) }
+
+  describe 'created_by_application_id' do
+    context 'when account is application-created' do
+      let(:record) { Fabricate :account, user: Fabricate(:user, created_by_application: application) }
+      let(:application) { Fabricate :application }
+
+      it { is_expected.to include('created_by_application_id' => application.id.to_s) }
+    end
+  end
+
+  describe 'invited_by_account_id' do
+    context 'when account was invited' do
+      let(:record) { Fabricate :account, user: Fabricate(:user, invite: invite) }
+      let(:invite) { Fabricate :invite }
+
+      it { is_expected.to include('invited_by_account_id' => invite.user.account.id.to_s) }
+    end
+  end
+end

spec/serializers/rest/admin/cohort_serializer_spec.rb

@@ -0,0 +1,19 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+RSpec.describe REST::Admin::CohortSerializer do
+  subject { serialized_record_json(record, described_class) }
+
+  let(:record) { Admin::Metrics::Retention.new('2024-01-01', '2024-01-02', 'day').cohorts.first }
+
+  describe 'serialization' do
+    it 'returns expected values' do
+      expect(subject)
+        .to include(
+          'data' => be_a(Array),
+          'period' => /2024-01-01/
+        )
+    end
+  end
+end

spec/serializers/rest/admin/webhook_event_serializer_spec.rb

@@ -0,0 +1,33 @@
+# frozen_string_literal: true
+
+require 'rails_helper'
+
+RSpec.describe REST::Admin::WebhookEventSerializer do
+  describe '.serializer_for' do
+    subject { described_class.serializer_for(model, {}) }
+
+    context 'with an Account model' do
+      let(:model) { Account.new }
+
+      it { is_expected.to eq(REST::Admin::AccountSerializer) }
+    end
+
+    context 'with a Report model' do
+      let(:model) { Report.new }
+
+      it { is_expected.to eq(REST::Admin::ReportSerializer) }
+    end
+
+    context 'with a Status model' do
+      let(:model) { Status.new }
+
+      it { is_expected.to eq(REST::StatusSerializer) }
+    end
+
+    context 'with an Array' do
+      let(:model) { [] }
+
+      it { is_expected.to eq(ActiveModel::Serializer::CollectionSerializer) }
+    end
+  end
+end