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322/**
* next/head shim unit tests.
*
* Mirrors test cases from Next.js test/unit/next-head-rendering.test.ts,
* plus comprehensive coverage for vinext's Head SSR collection, HTML
* generation, allowed tags, and escaping.
*/
import { describe, it, expect, vi, beforeEach } from "vitest";
import React from "react";
import ReactDOMServer from "react-dom/server";
import Head, { resetSSRHead, getSSRHeadHTML, escapeAttr } from "../packages/vinext/src/shims/head.js";
// ─── SSR rendering (mirrors Next.js test/unit/next-head-rendering.test.ts) ──
describe("Rendering next/head", () => {
beforeEach(() => {
resetSSRHead();
});
it("should render outside of Next.js without error", () => {
// Next.js test: renderToString(<><Head /><p>hello world</p></>)
// Verifies Head doesn't throw when used standalone
const html = ReactDOMServer.renderToString(
React.createElement(React.Fragment, null,
React.createElement(Head, null),
React.createElement("p", null, "hello world"),
),
);
expect(html).toContain("hello world");
});
it("returns null (no rendered output in body)", () => {
const html = ReactDOMServer.renderToString(
React.createElement(Head, null,
React.createElement("title", null, "My Page"),
),
);
// Head always returns null — elements are collected, not rendered inline
expect(html).toBe("");
});
});
// ─── SSR head collection ────────────────────────────────────────────────
describe("Head SSR collection", () => {
beforeEach(() => {
resetSSRHead();
});
it("collects title element", () => {
ReactDOMServer.renderToString(
React.createElement(Head, null,
React.createElement("title", null, "My Page Title"),
),
);
const headHtml = getSSRHeadHTML();
expect(headHtml).toContain("<title");
expect(headHtml).toContain("My Page Title");
expect(headHtml).toContain("</title>");
expect(headHtml).toContain('data-vinext-head="true"');
});
it("collects meta elements as self-closing", () => {
ReactDOMServer.renderToString(
React.createElement(Head, null,
React.createElement("meta", { name: "description", content: "A test page" }),
),
);
const headHtml = getSSRHeadHTML();
expect(headHtml).toContain('<meta name="description" content="A test page"');
expect(headHtml).toContain("/>"); // self-closing
expect(headHtml).not.toContain("</meta>");
});
it("collects link elements as self-closing", () => {
ReactDOMServer.renderToString(
React.createElement(Head, null,
React.createElement("link", { rel: "stylesheet", href: "/styles.css" }),
),
);
const headHtml = getSSRHeadHTML();
expect(headHtml).toContain('<link rel="stylesheet" href="/styles.css"');
expect(headHtml).toContain("/>"); // self-closing
});
it("collects style elements", () => {
ReactDOMServer.renderToString(
React.createElement(Head, null,
React.createElement("style", null, "body { color: red; }"),
),
);
const headHtml = getSSRHeadHTML();
expect(headHtml).toContain("<style");
// Text content is HTML-escaped
expect(headHtml).toContain("body { color: red; }");
});
it("collects script elements", () => {
ReactDOMServer.renderToString(
React.createElement(Head, null,
React.createElement("script", { src: "/analytics.js", async: true }),
),
);
const headHtml = getSSRHeadHTML();
expect(headHtml).toContain('<script src="/analytics.js" async');
expect(headHtml).toContain("</script>");
});
it("collects base element as self-closing", () => {
ReactDOMServer.renderToString(
React.createElement(Head, null,
React.createElement("base", { href: "https://example.com/" }),
),
);
const headHtml = getSSRHeadHTML();
expect(headHtml).toContain('<base href="https://example.com/"');
expect(headHtml).toContain("/>"); // self-closing
});
it("collects noscript elements", () => {
ReactDOMServer.renderToString(
React.createElement(Head, null,
React.createElement("noscript", null, "JavaScript is required"),
),
);
const headHtml = getSSRHeadHTML();
expect(headHtml).toContain("<noscript");
expect(headHtml).toContain("JavaScript is required");
expect(headHtml).toContain("</noscript>");
});
it("collects multiple head elements in order", () => {
ReactDOMServer.renderToString(
React.createElement(Head, null,
React.createElement("title", null, "First"),
React.createElement("meta", { name: "viewport", content: "width=device-width" }),
React.createElement("link", { rel: "icon", href: "/favicon.ico" }),
),
);
const headHtml = getSSRHeadHTML();
expect(headHtml).toContain("First");
expect(headHtml).toContain("viewport");
expect(headHtml).toContain("favicon.ico");
});
it("resets head between renders", () => {
ReactDOMServer.renderToString(
React.createElement(Head, null,
React.createElement("title", null, "Page 1"),
),
);
expect(getSSRHeadHTML()).toContain("Page 1");
resetSSRHead();
ReactDOMServer.renderToString(
React.createElement(Head, null,
React.createElement("title", null, "Page 2"),
),
);
const headHtml = getSSRHeadHTML();
expect(headHtml).toContain("Page 2");
expect(headHtml).not.toContain("Page 1");
});
it("returns empty string when no head elements", () => {
const headHtml = getSSRHeadHTML();
expect(headHtml).toBe("");
});
});
// ─── Disallowed tags ────────────────────────────────────────────────────
describe("Head disallowed tags", () => {
beforeEach(() => {
resetSSRHead();
});
it("ignores <div> tag (not allowed in head)", () => {
const warn = vi.spyOn(console, "warn").mockImplementation(() => {});
ReactDOMServer.renderToString(
React.createElement(Head, null,
React.createElement("div", null, "bad"),
),
);
const headHtml = getSSRHeadHTML();
expect(headHtml).not.toContain("<div");
expect(headHtml).toBe("");
warn.mockRestore();
});
it("ignores <iframe> tag (security concern)", () => {
const warn = vi.spyOn(console, "warn").mockImplementation(() => {});
ReactDOMServer.renderToString(
React.createElement(Head, null,
React.createElement("iframe", { src: "https://evil.com" }),
),
);
const headHtml = getSSRHeadHTML();
expect(headHtml).not.toContain("<iframe");
expect(headHtml).toBe("");
warn.mockRestore();
});
it("ignores component elements (non-string type)", () => {
function CustomComponent() { return React.createElement("meta", { name: "custom" }); }
ReactDOMServer.renderToString(
React.createElement(Head, null,
React.createElement(CustomComponent),
),
);
const headHtml = getSSRHeadHTML();
// Component elements are ignored because child.type is not a string
expect(headHtml).toBe("");
});
it("keeps allowed tags while ignoring disallowed ones", () => {
const warn = vi.spyOn(console, "warn").mockImplementation(() => {});
ReactDOMServer.renderToString(
React.createElement(Head, null,
React.createElement("title", null, "Good"),
React.createElement("div", null, "Bad"),
React.createElement("meta", { name: "good" }),
),
);
const headHtml = getSSRHeadHTML();
expect(headHtml).toContain("Good");
expect(headHtml).toContain('name="good"');
expect(headHtml).not.toContain("<div");
warn.mockRestore();
});
});
// ─── HTML/Attribute escaping ────────────────────────────────────────────
describe("Head escaping", () => {
beforeEach(() => {
resetSSRHead();
});
it("escapes HTML in text content", () => {
ReactDOMServer.renderToString(
React.createElement(Head, null,
React.createElement("title", null, 'Page <script>alert("xss")</script>'),
),
);
const headHtml = getSSRHeadHTML();
expect(headHtml).toContain("<script>");
expect(headHtml).not.toContain("<script>alert");
});
it("escapes HTML in attribute values", () => {
ReactDOMServer.renderToString(
React.createElement(Head, null,
React.createElement("meta", { name: 'test"value', content: "a<b>c&d" }),
),
);
const headHtml = getSSRHeadHTML();
expect(headHtml).toContain(""");
expect(headHtml).toContain("<");
expect(headHtml).toContain("&");
});
it("renders dangerouslySetInnerHTML raw on SSR", () => {
ReactDOMServer.renderToString(
React.createElement(Head, null,
React.createElement("script", {
dangerouslySetInnerHTML: { __html: 'console.log("hello")' },
}),
),
);
const headHtml = getSSRHeadHTML();
expect(headHtml).toContain('console.log("hello")');
});
it("converts className to class attribute", () => {
ReactDOMServer.renderToString(
React.createElement(Head, null,
React.createElement("style", { className: "critical" }, "body{}"),
),
);
const headHtml = getSSRHeadHTML();
expect(headHtml).toContain('class="critical"');
expect(headHtml).not.toContain("className");
});
it("renders boolean true attributes as bare attribute name", () => {
ReactDOMServer.renderToString(
React.createElement(Head, null,
React.createElement("script", { src: "/app.js", async: true, defer: true }),
),
);
const headHtml = getSSRHeadHTML();
expect(headHtml).toContain(" async ");
expect(headHtml).toContain(" defer ");
});
});
// ─── escapeAttr utility ─────────────────────────────────────────────────
describe("escapeAttr", () => {
it("escapes ampersand", () => {
expect(escapeAttr("a&b")).toBe("a&b");
});
it("escapes double quotes", () => {
expect(escapeAttr('a"b')).toBe("a"b");
});
it("escapes angle brackets", () => {
expect(escapeAttr("a<b>c")).toBe("a<b>c");
});
it("returns safe strings unchanged", () => {
expect(escapeAttr("hello world")).toBe("hello world");
});
it("escapes all special chars together", () => {
expect(escapeAttr('&"<>')).toBe("&"<>");
});
});