school_compare/nextjs-app/__tests__/app/blogMetadata.test.ts

/**
 * The blog index imports getCachedPayload, which pulls in Payload — ESM-only,
 * and next/jest will not transform node_modules. Mocking that one module keeps
 * the page's metadata testable without loading the CMS; the mock is never
 * called, because `metadata` is a static export evaluated at import time.
 */
jest.mock('@/lib/payload', () => ({ getCachedPayload: jest.fn() }));

import { metadata } from '@/app/(frontend)/blog/page';
import { blogPostingJsonLd, breadcrumbJsonLd } from '@/lib/jsonld';

const post = {
  title: 'What the data cannot tell you',
  slug: 'what-the-data-cannot-tell-you',
  excerpt: 'Results describe one year group on a handful of days.',
  publishedAt: '2026-09-15T00:00:00.000Z',
};

describe('/blog metadata', () => {
  it('canonicalises to the bare path', () => {
    expect(metadata.alternates?.canonical)
      .toBe('https://www.schoolcompare.co.uk/blog');
  });
});

describe('BlogPosting structured data', () => {
  it('names the same Person entity the about page declares', () => {
    // By @id, not by repeating the person: search engines must resolve every
    // post and the about page to one author entity, or the site has several.
    const ld = blogPostingJsonLd(post, { namedAuthor: true });
    expect(ld['@type']).toBe('BlogPosting');
    expect(ld.author['@id']).toBe('https://www.schoolcompare.co.uk/about#tudor');
    expect(ld.publisher['@id']).toBe('https://www.schoolcompare.co.uk#organization');
  });

  it('attributes to the organization when the about page is dark', () => {
    /*
     * The two flags are independent, so blog-on-about-off is a reachable
     * state. The Person entity lives at /about#tudor and that URL 404s while
     * the flag is dark, so claiming it would declare an author that resolves
     * to nothing — worse for the blog's credibility than having no named
     * author at all. Attribute to the publisher instead.
     */
    const ld = blogPostingJsonLd(post, { namedAuthor: false });
    expect(ld.author['@id']).toBe('https://www.schoolcompare.co.uk#organization');
    expect(JSON.stringify(ld)).not.toContain('/about');
  });

  it('carries a self-referencing canonical url and the publish date', () => {
    const ld = blogPostingJsonLd(post, { namedAuthor: true });
    expect(ld.url).toBe(
      'https://www.schoolcompare.co.uk/blog/what-the-data-cannot-tell-you',
    );
    expect(ld.datePublished).toBe('2026-09-15T00:00:00.000Z');
  });
});

describe('breadcrumbs', () => {
  it('places the post under the blog index', () => {
    const ld = breadcrumbJsonLd(post);
    expect(ld.itemListElement[0].item).toBe('https://www.schoolcompare.co.uk/blog');
    expect(ld.itemListElement[1].item).toBe(
      'https://www.schoolcompare.co.uk/blog/what-the-data-cannot-tell-you',
    );
  });
});