layout/style/test/test_media_query_list.html

<!DOCTYPE HTML>
<html>
<!--
https://bugzilla.mozilla.org/show_bug.cgi?id=542058
-->
<head>
  <title>Test for MediaQueryList (Bug 542058)</title>
  <script src="/tests/SimpleTest/SimpleTest.js"></script>
  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
</head>
<body onload="run()">
<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=542058">Mozilla Bug 542058</a>
<iframe id="subdoc" src="about:blank"></iframe>
<div id="content" style="display:none"></div>
<pre id="test">
<script type="application/javascript">

/** Test for MediaQueryList (Bug 542058) **/

SimpleTest.waitForExplicitFinish();

function tick() {
  // MediaQueryList events are guaranteed to run before requestAnimationFrame
  // per spec.
  return new Promise(r => requestAnimationFrame(r));
}

async function run() {
  var iframe = document.getElementById("subdoc");
  var subdoc = iframe.contentDocument;
  var subwin = iframe.contentWindow;
  var subroot = subdoc.documentElement;

  var content_div = document.getElementById("content");
  content_div.style.font = "initial";
  var em_size =
    getComputedStyle(content_div).fontSize.match(/^(\d+)px$/)[1];

  var w = Math.floor(em_size * 9.3);
  var h = Math.floor(em_size * 4.2);
  iframe.style.width = w + "px";
  iframe.style.height = h + "px";
  subroot.offsetWidth; // flush layout
  await tick();

  function setup_mql(str) {
    var obj = {
      str: str,
      mql: subwin.matchMedia(str),
      notifyCount: 0,
      listener: function(event) {
                  ok(event instanceof subwin.MediaQueryListEvent,
                     "correct argument to listener: " + obj.str);
                  is(event.media, obj.mql.media,
                     "correct media in the event: " + obj.str);
                  is(event.target, obj.mql,
                     "correct target in the event: " + obj.str);
                  ++obj.notifyCount;
                  // Test the last match result only on odd
                  // notifications.
                  if (obj.notifyCount & 1) {
                    obj.lastOddMatchResult = event.target.matches;
                  }
                }
    }
    obj.mql.addListener(obj.listener);
    return obj;
  }

  function finish_mql(obj) {
    obj.mql.removeListener(obj.listener);
  }

  var w_exact_w = setup_mql("(width: " + w + "px)");
  var w_min_9em = setup_mql("(min-width : 9em)");
  var w_min_10em = setup_mql("(  min-width: 10em ) ");
  var w_max_9em = setup_mql("(max-width: 9em)");
  var w_max_10em = setup_mql("(max-width: 10em)");

  is(w_exact_w.mql.media, "(width: " + w + "px)", "serialization");
  is(w_min_9em.mql.media, "(min-width: 9em)", "serialization");
  is(w_min_10em.mql.media, "(min-width: 10em)", "serialization");
  is(w_max_9em.mql.media, "(max-width: 9em)", "serialization");
  is(w_max_10em.mql.media, "(max-width: 10em)", "serialization");

  function check_match(obj, expected, desc) {
    is(obj.mql.matches, expected,
       obj.str + " media query list .matches " + desc);
    if (obj.notifyCount & 1) { // odd notifications only
      is(obj.lastOddMatchResult, expected,
       obj.str + " media query list last notify result " + desc);
    }
  }
  function check_notify(obj, expected, desc) {
    is(obj.notifyCount, expected,
       obj.str + " media query list .notify count " + desc);
  }
  check_match(w_exact_w, true, "initially");
  check_notify(w_exact_w, 0, "initially");
  check_match(w_min_9em, true, "initially");
  check_notify(w_min_9em, 0, "initially");
  check_match(w_min_10em, false, "initially");
  check_notify(w_min_10em, 0, "initially");
  check_match(w_max_9em, false, "initially");
  check_notify(w_max_9em, 0, "initially");
  check_match(w_max_10em, true, "initially");
  check_notify(w_max_10em, 0, "initially");

  var w2 = Math.floor(em_size * 10.3);
  iframe.style.width = w2 + "px";
  subroot.offsetWidth; // flush layout
  await tick();

  check_match(w_exact_w, false, "after width increase to around 10.3em");
  check_notify(w_exact_w, 1, "after width increase to around 10.3em");
  check_match(w_min_9em, true, "after width increase to around 10.3em");
  check_notify(w_min_9em, 0, "after width increase to around 10.3em");
  check_match(w_min_10em, true, "after width increase to around 10.3em");
  check_notify(w_min_10em, 1, "after width increase to around 10.3em");
  check_match(w_max_9em, false, "after width increase to around 10.3em");
  check_notify(w_max_9em, 0, "after width increase to around 10.3em");
  check_match(w_max_10em, false, "after width increase to around 10.3em");
  check_notify(w_max_10em, 1, "after width increase to around 10.3em");

  var w3 = w * 2;
  iframe.style.width = w3 + "px";
  subroot.offsetWidth; // flush layout
  await tick();

  check_match(w_exact_w, false, "after width double from original");
  check_notify(w_exact_w, 1, "after width double from original");
  check_match(w_min_9em, true, "after width double from original");
  check_notify(w_min_9em, 0, "after width double from original");
  check_match(w_min_10em, true, "after width double from original");
  check_notify(w_min_10em, 1, "after width double from original");
  check_match(w_max_9em, false, "after width double from original");
  check_notify(w_max_9em, 0, "after width double from original");
  check_match(w_max_10em, false, "after width double from original");
  check_notify(w_max_10em, 1, "after width double from original");

  SpecialPowers.setFullZoom(subwin, 2.0);
  subroot.offsetWidth; // flush layout
  await tick();

  check_match(w_exact_w, true, "after zoom");
  check_notify(w_exact_w, 2, "after zoom");
  check_match(w_min_9em, true, "after zoom");
  check_notify(w_min_9em, 0, "after zoom");
  check_match(w_min_10em, false, "after zoom");
  check_notify(w_min_10em, 2, "after zoom");
  check_match(w_max_9em, false, "after zoom");
  check_notify(w_max_9em, 0, "after zoom");
  check_match(w_max_10em, true, "after zoom");
  check_notify(w_max_10em, 2, "after zoom");

  SpecialPowers.setFullZoom(subwin, 1.0);

  await tick();

  finish_mql(w_exact_w);
  finish_mql(w_min_9em);
  finish_mql(w_min_10em);
  finish_mql(w_max_9em);
  finish_mql(w_max_10em);

  // Additional tests of listener mutation.
  {
    let received = [];
    let received_mql = [];
    function listener1(event) {
      received.push(1);
      received_mql.push(event.target);
    }
    function listener2(event) {
      received.push(2);
      received_mql.push(event.target);
    }

    iframe.style.width = "200px";
    subroot.offsetWidth; // flush layout
    await tick();

    let mql = subwin.matchMedia("(min-width: 150px)");
    mql.addListener(listener1);
    mql.addListener(listener1);
    mql.addListener(listener2);
    is(JSON.stringify(received), "[]", "listeners before notification");

    iframe.style.width = "100px";
    subroot.offsetWidth; // flush layout
    await tick();

    is(JSON.stringify(received), "[1,2]", "duplicate listeners removed");
    received = [];
    mql.removeListener(listener1);

    iframe.style.width = "200px";
    subroot.offsetWidth; // flush layout
    await tick();

    is(JSON.stringify(received), "[2]", "listener removal");
    received = [];
    mql.addListener(listener1);

    iframe.style.width = "100px";
    subroot.offsetWidth; // flush layout
    await tick();

    is(JSON.stringify(received), "[2,1]", "listeners notified in order");
    received = [];
    mql.addListener(listener2);

    iframe.style.width = "200px";
    subroot.offsetWidth; // flush layout
    await tick();

    is(JSON.stringify(received), "[2,1]", "add of existing listener is no-op");
    received = [];
    mql.addListener(listener1);

    iframe.style.width = "100px";
    subroot.offsetWidth; // flush layout
    await tick();

    is(JSON.stringify(received), "[2,1]", "add of existing listener is no-op");
    mql.removeListener(listener2);
    received = [];
    received_mql = [];

    var mql2 = subwin.matchMedia("(min-width: 160px)");
    mql2.addListener(listener1);
    mql.addListener(listener2);

    iframe.style.width = "200px";
    subroot.offsetWidth; // flush layout
    await tick();

    // mql (1, 2), mql2 (1)
    is(JSON.stringify(received), "[1,2,1]",
       "notification of lists in order created");
    is(received_mql[0], mql,
       "notification of lists in order created");
    is(received_mql[1], mql,
       "notification of lists in order created");
    is(received_mql[2], mql2,
       "notification of lists in order created");
    received = [];
    received_mql = [];

    function removing_listener(event) {
      received.push(3);
      received_mql.push(event.target);
      event.target.removeListener(listener2);
      mql2.removeListener(listener1);
    }

    mql.addListener(removing_listener);
    mql.removeListener(listener2);
    mql.addListener(listener2); // after removing_listener (3)

    iframe.style.width = "100px";
    subroot.offsetWidth; // flush layout
    await tick();

    // mql(1, 3)
    is(JSON.stringify(received), "[1,3]",
       "listeners still notified after removed if change was before");
    is(received_mql[0], mql,
       "notification order (removal tests)");
    is(received_mql[1], mql,
       "notification order (removal tests)");
    received = [];
    received_mql = [];

    iframe.style.width = "200px";
    subroot.offsetWidth; // flush layout
    await tick();

    // mql(1, 3)
    is(JSON.stringify(received), "[1,3]",
       "listeners not notified for changes after their removal");
    is(received_mql[0], mql,
       "notification order (removal tests)");
    is(received_mql[1], mql,
       "notification order (removal tests)");
  }

  /* Bug 753777: test that things work in a freshly-created iframe */
  {
    let newIframe = document.createElement("iframe");
    document.body.appendChild(newIframe);

    is(newIframe.contentWindow.matchMedia("all").matches, true,
       "matchMedia should work in newly-created iframe");
    is(newIframe.contentWindow.matchMedia("(min-width: 1px)").matches, true,
       "(min-width: 1px) should match in newly-created iframe");
    is(newIframe.contentWindow.matchMedia("(max-width: 1px)").matches, false,
       "(max-width: 1px) should not match in newly-created iframe");

    document.body.removeChild(newIframe);
  }

  /* Bug 716751: listeners lost due to GC */
  var gc_received = [];
  {
    let received = [];
    let listener1 = function(event) {
      gc_received.push(1);
    }

    iframe.style.width = "200px";
    subroot.offsetWidth; // flush layout
    await tick();

    let mql = subwin.matchMedia("(min-width: 150px)");
    mql.addListener(listener1);
    is(JSON.stringify(gc_received), "[]", "GC test: before notification");

    iframe.style.width = "100px";
    subroot.offsetWidth; // flush layout
    await tick();

    is(JSON.stringify(gc_received), "[1]", "GC test: after notification 1");

    // Because of conservative GC, we need to go back to the event loop
    // to GC properly.
    setTimeout(step2, 0);
  }

  async function step2() {
    SpecialPowers.DOMWindowUtils.garbageCollect();

    iframe.style.width = "200px";
    subroot.offsetWidth; // flush layout
    await tick();

    is(JSON.stringify(gc_received), "[1,1]", "GC test: after notification 2");

    bug1270626();
  }

  /* Bug 1270626: listeners that throw exceptions */
  async function bug1270626() {
    var throwingListener = function(event) {
      throw "error";
    }

    iframe.style.width = "200px";
    subroot.offsetWidth; // flush layout
    await tick();

    var mql = subwin.matchMedia("(min-width: 150px)");
    mql.addListener(throwingListener);

    SimpleTest.expectUncaughtException(true);
    is(SimpleTest.isExpectingUncaughtException(), true,
       "should be waiting for an uncaught exception");

    iframe.style.width = "100px";
    subroot.offsetWidth; // flush layout
    await tick();

    is(SimpleTest.isExpectingUncaughtException(), false,
       "should have gotten an uncaught exception");

    SimpleTest.finish();
  }
}

</script>
</pre>
</body>
</html>