Why did this test pass?

The spec file

Every test on this page belongs in one file under this header, for example tests/diagnose.spec.ts. The tests are plain JavaScript, and Playwright runs them unchanged from a .ts file. Run it with the practice lab's config to see these results yourself.

import { test, expect } from "@playwright/test";

// The practice shop's published demo password (see /practice). It unlocks nothing else.
const SHOP_PASSWORD = "practice-only";

test.beforeEach(async ({ page }) => {
  await page.goto("/practice/shop");
  await page.getByLabel("Username").fill("shopper");
  await page.getByLabel("Password").fill(SHOP_PASSWORD);
  await page.getByRole("button", { name: "Log in" }).click();
});

async function addToCart(page, name) {
  await page.getByTestId("product").filter({ hasText: name }).getByRole("button", { name: "Add to cart" }).click();
}

async function checkOut(page, names) {
  for (const name of names) await addToCart(page, name);
  await page.getByTestId("cart-link").click();
  await page.getByRole("button", { name: "Checkout" }).click();
  await page.getByTestId("firstName").fill("Ada");
  await page.getByTestId("lastName").fill("Lovelace");
  await page.getByTestId("postalCode").fill("10115");
  await page.getByRole("button", { name: "Continue" }).click();
}