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425/**
* Next.js Compatibility Tests: metadata
*
* Ported from: https://github.com/vercel/next.js/blob/canary/test/e2e/app-dir/metadata/metadata.test.ts
*
* Tests metadata rendering in SSR HTML:
* - Static metadata (title, description, keywords, etc.)
* - Title template (layout provides template, page provides value)
* - OpenGraph tags
* - Twitter card tags
* - Robots tags
* - Alternate/canonical links
* - generateMetadata() with dynamic params
*
* NOTE: Most Next.js metadata tests use Playwright (browser.eval('document.title')).
* We test at the SSR level by checking HTML <head> content directly.
*
* Fixture pages live in:
* - fixtures/app-basic/app/nextjs-compat/metadata-*
*/
import { describe, it, expect, beforeAll, afterAll } from "vitest";
import type { ViteDevServer } from "vite";
import { APP_FIXTURE_DIR, startFixtureServer, fetchHtml } from "../helpers.js";
describe("Next.js compat: metadata", () => {
let server: ViteDevServer;
let baseUrl: string;
beforeAll(async () => {
({ server, baseUrl } = await startFixtureServer(APP_FIXTURE_DIR, {
appRouter: true,
}));
// Warm up
await fetch(`${baseUrl}/`).catch(() => {});
}, 60_000);
afterAll(async () => {
await server?.close();
});
// ── Title and description ────────────────────────────────────
// Next.js: 'should support title and description'
// Source: https://github.com/vercel/next.js/blob/canary/test/e2e/app-dir/metadata/metadata.test.ts#L25-L32
it("should render title in <head>", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-title",
);
expect(html).toContain("<title>this is the page title</title>");
});
it("should render description meta tag", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-title",
);
expect(html).toMatch(
/meta\s+name="description"\s+content="this is the layout description"/,
);
});
// ── Title template ───────────────────────────────────────────
// Next.js: 'should support title template'
// Source: https://github.com/vercel/next.js/blob/canary/test/e2e/app-dir/metadata/metadata.test.ts#L34-L38
it("should apply title template from layout", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-title-template",
);
// Layout has template "%s | Layout", page has title "Page"
// Result should be "Page | Layout"
expect(html).toContain("<title>Page | Layout</title>");
});
// Next.js: 'should support stashed title in one layer'
// Source: https://github.com/vercel/next.js/blob/canary/test/e2e/app-dir/metadata/metadata.test.ts#L40-L44
it("should apply title template to child page", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-title-template/child",
);
// Layout template "%s | Layout", child page title "Extra Page"
expect(html).toContain("<title>Extra Page | Layout</title>");
});
// ── Basic metadata tags ──────────────────────────────────────
// Next.js: 'should support other basic tags'
// Source: https://github.com/vercel/next.js/blob/canary/test/e2e/app-dir/metadata/metadata.test.ts#L52-L89
it("should render generator meta tag", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-basic",
);
expect(html).toMatch(/meta\s+name="generator"\s+content="next\.js"/);
});
it("should render application-name meta tag", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-basic",
);
expect(html).toMatch(/meta\s+name="application-name"\s+content="test"/);
});
it("should render referrer meta tag", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-basic",
);
expect(html).toMatch(
/meta\s+name="referrer"\s+content="origin-when-cross-origin"/,
);
});
it("should render keywords meta tag", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-basic",
);
// Next.js joins keywords with "," (no space) — match that exactly
expect(html).toMatch(/meta\s+name="keywords"\s+content="next\.js,react,javascript"/);
});
it("should render author meta tags", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-basic",
);
expect(html).toMatch(/meta\s+name="author"\s+content="huozhi"/);
expect(html).toMatch(/meta\s+name="author"\s+content="tree"/);
});
it("should render creator meta tag", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-basic",
);
expect(html).toMatch(/meta\s+name="creator"\s+content="shu"/);
});
it("should render publisher meta tag", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-basic",
);
expect(html).toMatch(/meta\s+name="publisher"\s+content="vercel"/);
});
it("should render robots meta tag", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-basic",
);
expect(html).toMatch(/meta\s+name="robots"\s+content="index, follow"/);
});
it("should render format-detection meta tag", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-basic",
);
expect(html).toMatch(/meta\s+name="format-detection"/);
expect(html).toMatch(/telephone=no/);
});
// ── OpenGraph ────────────────────────────────────────────────
// Next.js: 'should support opengraph tags'
// Source: https://github.com/vercel/next.js/blob/canary/test/e2e/app-dir/metadata/metadata.test.ts#L175-L211
it("should render og:title", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-opengraph",
);
expect(html).toMatch(/meta\s+property="og:title"\s+content="My custom title"/);
});
it("should render og:description", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-opengraph",
);
expect(html).toMatch(
/meta\s+property="og:description"\s+content="My custom description"/,
);
});
it("should render og:url", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-opengraph",
);
expect(html).toMatch(
/meta\s+property="og:url"\s+content="https:\/\/example\.com"/,
);
});
it("should render og:site_name", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-opengraph",
);
expect(html).toMatch(
/meta\s+property="og:site_name"\s+content="My custom site name"/,
);
});
it("should render og:type", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-opengraph",
);
expect(html).toMatch(/meta\s+property="og:type"\s+content="website"/);
});
it("should render og:image", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-opengraph",
);
expect(html).toMatch(
/meta\s+property="og:image"\s+content="https:\/\/example\.com\/image\.png"/,
);
});
it("should render og:image:width and og:image:height", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-opengraph",
);
expect(html).toMatch(/meta\s+property="og:image:width"\s+content="800"/);
expect(html).toMatch(/meta\s+property="og:image:height"\s+content="600"/);
});
// ── Twitter ──────────────────────────────────────────────────
// Next.js: 'should support twitter card summary_large_image'
// Source: https://github.com/vercel/next.js/blob/canary/test/e2e/app-dir/metadata/metadata.test.ts#L308-L323
it("should render twitter:card", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-twitter",
);
expect(html).toMatch(
/meta\s+name="twitter:card"\s+content="summary_large_image"/,
);
});
it("should render twitter:title", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-twitter",
);
expect(html).toMatch(/meta\s+name="twitter:title"\s+content="Twitter Title"/);
});
it("should render twitter:description", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-twitter",
);
expect(html).toMatch(
/meta\s+name="twitter:description"\s+content="Twitter Description"/,
);
});
it("should render twitter:image", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-twitter",
);
expect(html).toMatch(
/meta\s+name="twitter:image"\s+content="https:\/\/twitter\.com\/image\.png"/,
);
});
// ── Robots (complex) ────────────────────────────────────────
// Next.js: 'should support robots tags'
// Source: https://github.com/vercel/next.js/blob/canary/test/e2e/app-dir/metadata/metadata.test.ts#L113-L121
it("should render complex robots meta tag", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-robots",
);
expect(html).toMatch(/meta\s+name="robots"/);
// Should contain noindex and follow
expect(html).toMatch(/noindex/);
expect(html).toMatch(/follow/);
});
it("should render googlebot meta tag", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-robots",
);
expect(html).toMatch(/meta\s+name="googlebot"/);
});
// ── Alternates ───────────────────────────────────────────────
// Next.js: 'should support alternate tags'
// Source: https://github.com/vercel/next.js/blob/canary/test/e2e/app-dir/metadata/metadata.test.ts#L129-L152
it("should render canonical link", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-alternates",
);
expect(html).toMatch(
/link\s+rel="canonical"\s+href="https:\/\/example\.com\/alternates"/,
);
});
it("should render hreflang alternate links", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-alternates",
);
// React JSX renders as hrefLang (camelCase) in HTML output
expect(html).toMatch(/hrefLang="en-US"/i);
expect(html).toMatch(/hrefLang="de-DE"/i);
});
// ── generateMetadata with dynamic params ─────────────────────
// Next.js: 'should support generateMetadata dynamic props'
// Source: https://github.com/vercel/next.js/blob/canary/test/e2e/app-dir/metadata/metadata.test.ts#L174-L184
it("should render title from generateMetadata with params", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-generate/my-slug",
);
expect(html).toContain("<title>params - my-slug</title>");
});
it("should render description from generateMetadata with params", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-generate/test-page",
);
expect(html).toMatch(
/meta\s+name="description"\s+content="Description for test-page"/,
);
});
// ── Default charset and viewport injection ────────────────────
// Next.js always injects <meta charset="utf-8"> and
// <meta name="viewport" content="width=device-width, initial-scale=1">
// on every page, even when no metadata or viewport is exported.
it("should always include charset meta tag in SSR output", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-title",
);
expect(html).toMatch(/meta\s+charSet="utf-8"|meta\s+charset="utf-8"/i);
});
it("should always include viewport meta tag in SSR output", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-title",
);
expect(html).toMatch(/meta\s+name="viewport"\s+content="width=device-width, initial-scale=1"/);
});
it("should include charset and viewport even on pages with only OG metadata", async () => {
const { html } = await fetchHtml(
baseUrl,
"/nextjs-compat/metadata-opengraph",
);
expect(html).toMatch(/meta\s+charSet="utf-8"|meta\s+charset="utf-8"/i);
expect(html).toMatch(/meta\s+name="viewport"/);
});
// ── Browser-only tests (documented, not ported) ──────────────
//
// N/A: 'should apply metadata when navigating client-side'
// Requires Playwright — tests title updates on client-side navigation
//
// N/A: 'should support title template' (browser eval)
// Some template tests use browser.eval('document.title') — ported above at SSR level
//
// N/A: 'should support apple related tags itunes and appWebApp'
// Would need dedicated fixture page
//
// N/A: 'should support socials related tags'
// Would need dedicated fixture page (fb:app_id, pinterest)
//
// N/A: 'should support verification tags'
// Would need dedicated fixture page
//
// N/A: 'should support appLinks tags'
// Would need dedicated fixture page
//
// N/A: 'should support icons field' (basic, string, descriptor)
// Would need dedicated fixture pages — partially covered by existing vinext tests
//
// N/A: 'should pick up opengraph-image and twitter-image as static metadata files'
// Tests file-based metadata images — different feature
//
// N/A: 'should support twitter player/app cards'
// Would need dedicated fixture pages
//
// N/A: Static routes (favicon.ico, robots.txt, sitemap.xml)
// Tests file serving, not metadata export — separate feature
//
// N/A: 'metadataBase' URL resolution tests
// Would need dedicated fixture pages
//
// N/A: HMR/hot reload tests
// Tests dev server file watching
//
// N/A: Cache deduping tests
// Tests React.cache() with metadata — Playwright required
//
// N/A: Viewport tests
// Partially covered by existing vinext tests (tests/app-router.test.ts)
});