import { describe, it, before, after } from "node:test"; import assert from "node:assert/strict"; import { chromium, type Browser, type Page } from "playwright"; import { discoverLazyAssetsInPage } from "../src/capture/capture.js"; const ESBUILD_SHIM = "globalThis.__name = globalThis.__name || ((fn) => fn);" + "globalThis.__defProp = globalThis.__defProp || Object.defineProperty;"; const VW = 1280, VH = 800; const BASE = "https://example.com/page/"; // --------------------------------------------------------------------------- // Item 2: extended lazy-asset discovery sweep (in-page discovery function). // --------------------------------------------------------------------------- describe("lazySweep: discoverLazyAssetsInPage", () => { let browser: Browser; before(async () => { browser = await chromium.launch(); }); after(async () => { await browser.close(); }); const discover = async (bodyHtml: string): Promise => { const page: Page = await browser.newPage(); await page.setViewportSize({ width: VW, height: VH }); await page.addInitScript(ESBUILD_SHIM); // A gives relative refs a stable absolute form to assert against. await page.setContent(`${bodyHtml}`); await page.evaluate(ESBUILD_SHIM); const refs = await page.evaluate(discoverLazyAssetsInPage); await page.close(); return refs; }; it("discovers img/source src + srcset inside

`); assert.ok(refs.includes(BASE + "hero.jpg"), "noscript img src"); assert.ok(refs.includes(BASE + "hero-2x.jpg"), "first srcset variant from noscript img"); assert.ok(refs.includes(BASE + "alt.webp"), "first srcset variant from noscript source"); }); it("discovers url(...) values from an element's inline style attribute", async () => { const refs = await discover(`

`); assert.ok(refs.includes(BASE + "bg.png"), "inline background-image url()"); assert.ok(refs.includes(BASE + "sprite.svg"), "inline background shorthand url()"); }); it("discovers data-background / data-background-image (raw URL and url(...) forms)", async () => { const refs = await discover(`

`); assert.ok(refs.includes(BASE + "lazybg.jpg"), "raw data-background URL"); assert.ok(refs.includes(BASE + "lazybg2.png"), "url()-wrapped data-background-image"); }); it("discovers the resolved src of an img[loading=lazy]", async () => { const refs = await discover(`

`); assert.ok(refs.includes(BASE + "belowfold.jpg")); }); it("drops data: URIs and dedupes + sorts", async () => { const refs = await discover(`

`); assert.equal(refs.filter((u) => u.endsWith("dup.png")).length, 1, "deduped across channels"); assert.equal(refs.some((u) => u.startsWith("data:")), false, "data: URIs dropped"); assert.deepEqual(refs, [...refs].sort(), "sorted"); }); it("returns nothing for a page with no lazy references", async () => { const refs = await discover(`

hello

`); // The eager is the walker's job, not this sweep — the sweep only harvests // the channels the walker misses. assert.deepEqual(refs, []); }); });