loading/preloader-template.tentative.html

<!doctype html>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<template>
  <script src="resources/dummy.js?in-template"></script>
  <link rel=stylesheet href="resources/dummy.css?in-template-1">
  <style>
    @import url("resources/dummy.css?in-template-2");
  </style>
</template>
<script>
  let t = async_test("Things inside templates are not preloaded");
  window.addEventListener("load", t.step_func(function() {
    let script = document.createElement("script");
    script.onload = t.step_func_done(function() {
      let entries = performance.getEntriesByType('resource');
      let found_outside_template = false;
      let found_in_template = [];
      for (let entry of entries) {
        if (entry.name.includes("outside-template")) {
          found_outside_template = true;
        }
        if (entry.name.includes("in-template")) {
          found_in_template.push(entry.name);
        }
      }
      assert_equals(found_in_template.length, 0, "Should not have preloaded stuff inside template element, got: " + found_in_template.join(", "));
      assert_true(found_outside_template, "Should have loaded script outside template element");
    });
    // The test is a bit racy because it expects that the first load ends
    // before this one. We try to make it the case via the tickle mechanism.
    script.src = "resources/dummy.js?outside-template&pipe=trickle(d1)";
    document.body.appendChild(script);
  }));
</script>