Add rspec test for email reseed behavior

spec/controllers/email_templates_reseed_spec.rb

@@ -0,0 +1,113 @@
+# frozen_string_literal: true
+
+require "rails_helper"
+
+# This test suite verifies the reseeding behavior of EmailTemplate models to ensure
+# that email templates are correctly handled (i.e., updated or removed) without duplication
+# upon reseeding the database with new seed data. It tests the initial seeding, updates to
+# templates, and the removal of templates that are no longer present in the seed data.
+RSpec.describe "EmailTemplate Reseed Behavior", type: :model do
+  # Define email content for initial seeding and subsequent updates. These blocks
+  # provide a flexible way to manage test data, allowing us to simulate changes in seed data
+  # across different test scenarios.
+  let(:form_submission_old) do
+    <<-FORM_SUBMISSION
+      <p>Submitted Information:</p>
+      <p>I am the original content of the form submission email.</p>
+    FORM_SUBMISSION
+  end
+
+  let(:request_info_email_old) do
+    <<-REQUEST_INFO_EMAIL
+      <p>Dear {{teacher_first_name}},</p>
+      <p>I am the original content of the request info email.</p>
+    REQUEST_INFO_EMAIL
+  end
+
+  let(:request_info_email_new) do
+    <<-REQUEST_INFO_EMAIL
+    <p>Dear {{teacher_first_name}},</p>
+    <p>I am NEW Template Content of the request info email.</p>
+    REQUEST_INFO_EMAIL
+  end
+
+  # Setup phase: Mocks the SeedData.emails call to return predetermined email content.
+  # This mimics the initial seeding process with specific email templates before each test.
+  # The `load Rails.root.join("db/seeds.rb")` line simulates the seeding action.
+  before do
+    allow(SeedData).to receive(:emails).and_return(
+      [
+        {
+          to: "[email protected], [email protected]",
+          body: form_submission_old,
+          path: "teacher_mailer/form_submission",
+          locale: nil,
+          handler: "liquid",
+          partial: false,
+          format: "html",
+          title: "Form Submission",
+          required: true,
+          subject: "Form Submission"
+        },
+        {
+          body: request_info_email_old,
+          to: "{{teacher_email}}, {{teacher_personal_email}}",
+          path: "teacher_mailer/request_info_email",
+          locale: nil,
+          handler: "liquid",
+          partial: false,
+          format: "html",
+          title: "Request Info Email",
+          required: true,
+          subject: "Request Info Email"
+        }
+      ])
+    # Initial seed with original data
+    load Rails.root.join("db/seeds.rb")
+  end
+
+  # This test verifies the entire reseed process by first checking the state after initial seeding,
+  # then mocking updated seed data, reseeding, and finally asserting the expected outcomes.
+  # It checks for the correct handling of both updated and removed email templates.
+  it "correctly handles email templates on reseed without duplication" do
+    # Verify original content
+    expect(EmailTemplate.count).to eq(2)
+    request_info_email = EmailTemplate.find_by(title: "Request Info Email")
+    expect(request_info_email.title).to eq("Request Info Email")
+    expect(request_info_email.body).to include("I am the original content of the request info email")
+
+    form_submission_email = EmailTemplate.find_by(title: "Form Submission")
+    expect(form_submission_email.title).to eq("Form Submission")
+    expect(form_submission_email.body).to include("I am the original content of the form submission email")
+
+    # Simulate an update to the seed data by changing the content of one email template
+    # and removing another. This prepares for the reseed to test how the application handles
+    # updated and removed templates.
+    allow(SeedData).to receive(:emails).and_return(
+      [
+        {
+          body: request_info_email_new,
+          to: "{{teacher_email}}, {{teacher_personal_email}}",
+          path: "teacher_mailer/request_info_email",
+          locale: nil,
+          handler: "liquid",
+          partial: false,
+          format: "html",
+          title: "Request Info Email",
+          required: true,
+          subject: "Request Info Email"
+        }
+      ])
+    load Rails.root.join("db/seeds.rb")
+
+    # Final assertions to verify that after reseeding, the email templates in the database
+    # reflect the updated seed data: updated content is present, and removed templates are absent.
+    expect(EmailTemplate.count).to eq(1)
+
+    request_info_email = EmailTemplate.find_by(title: "Request Info Email")
+    expect(request_info_email.title).to eq("Request Info Email")
+    expect(request_info_email.body).to include("NEW Template Content of the request info email")
+
+    expect(EmailTemplate.find_by(title: "Form Submission")).to be_nil
+  end
+end