mozilla-release/testing/web-platform/tests/payment-request/show-method-postmessage-manual.https.html

<!DOCTYPE html>
<meta charset="utf-8">
<title>Test for PaymentRequest.show() method</title>
<link rel="help" href="https://w3c.github.io/browser-payment-api/#show-method">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script>
"use strict";
setup({
  explicit_done: true,
  explicit_timeout: true,
  allow_uncaught_exception: true,
});

async function runUserActivation(button) {
  button.disabled = true;
  const { contentWindow: iframeWindow } = document.getElementById("iframe");
  const expectedId = "pass123";
  await Promise.resolve(); // next tick
  const promiseForResponse = new Promise(resolve => {
    window.onmessage = ({ data: { requestId } }) => resolve(requestId);
  });
  const ops = { id: expectedId, request: "show-payment-request" };
  iframeWindow.postMessage(ops, window.location.origin);
  promise_test(async () => {
    const actualId = await promiseForResponse;
    assert_equals(actualId, expectedId, "ids must match");
  }, button.textContent.trim());
  done();
}

</script>
<h2>Test PaymentRequest.show() triggered by user activation using postMessage()</h2>
<p>
  Tests that user activation works over postMessage().
</p>
<p>
  Click on bottom below. Hit "Pay".
</p>
<ol>
  <li>
    <button onclick="runUserActivation(this)">
      show() is triggered by user activation passed through postMessage() and a promise
    </button>
  </li>
</ol>
<iframe width="100%" id="iframe" src="show-method-postmessage-iframe.html" allowpaymentrequest></iframe>
<p>
  <small>
    If you find a buggy test, please <a href="https://github.com/web-platform-tests/wpt/issues">file a bug</a>
    and tag one of the <a href="https://github.com/web-platform-tests/wpt/blob/master/payment-request/META.yml">suggested reviewers</a>.
  </small>
</p>