chromium/third_party/blink/web_tests/external/wpt/css/css-overscroll-behavior/overscroll-behavior.html

<!doctype html>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/resources/testdriver.js"></script>
<script src="/resources/testdriver-actions.js"></script>
<script src="/resources/testdriver-vendor.js"></script>
<script src="/css/css-scroll-snap/support/common.js"></script>
<link rel="help" href="https://drafts.csswg.org/css-overscroll-behavior">

<style>
.outer {
  height: 400px;
  width: 1000px;
  background: white
}
.content {
  height: 600px;
  width: 1200px;
}
#root {
  overflow: scroll;
  height: 600px;
  width: 800px;
  background: white;
}
#container {
  overflow: scroll;
}
#non_scrollable {
  overflow: none;
}
#green {
  background: repeating-linear-gradient(to bottom right, green 15%, white 30%);
}
#blue {
  background: repeating-linear-gradient(to bottom right, blue 15%, white 30%);
}
</style>

<div id='root'>
  <div id='non_scrollable' class='outer'>
    <div id='green' class='content'></div>
  </div>
  <div id='container' class='outer'>
    <div id='blue' class='content'></div>
  </div>
</div>
<input type="button" id="btnDone" value="DONE" style="width: 100px; height: 50px;"/>
<h1>overscroll-behavior</h1>
<h4>Tests that overscroll-behavior prevents scroll-propagation in the area and direction as specified.</h4>
<ol>
  <li id="i1">Make two scrolls on <span style="color: blue">BLUE</span>, in this order: scroll UP (or drag down), then scroll LEFT (or drag right). Scroll (or drag) until nothing is scrolling. Then tap on DONE.</li>
  <li id="i2">Repeat the same scrolls as in step 1 and then tap on DONE.</li>
  <li id="i3">Repeat the same scrolls as in step 1 and then tap on DONE.</li>
  <li id="i4">Make two separate scrolls on <span style="color: green">GREEN</span>, in this order: scroll UP (or drag down), then scroll LEFT (or drag right). Scroll (or drag) until nothing is scrolling. Then tap on DONE.</li>
</ol>


<script>
setup({explicit_timeout: true});
const container = document.getElementById('container');
const non_scrollable = document.getElementById('non_scrollable');
const root = document.getElementById('root');
const btnDone = document.getElementById('btnDone');
var test = async_test("overscroll-behavior prevents scroll-propagation in the area and direction as specified");
var instruction1 = document.getElementById("i1");
var instruction2 = document.getElementById("i2");
var instruction3 = document.getElementById("i3");
var instruction4 = document.getElementById("i4");
var actions_promise;

scrollTop = () => container.scrollTop;
scrollLeft = () => container.scrollLeft;

function smoothScrollByXY(xPosition, yPosition, xScrollOffset, yScrollOffset) {
  return new test_driver.Actions()
      .scroll(xPosition, yPosition, xScrollOffset, yScrollOffset)
      .send();
}

function setUpForRoot(offset) {
  root.scrollTop = offset;
  root.scrollLeft = offset;
}

function setUpForContainer(offset) {
  container.scrollTop = offset;
  container.scrollLeft = offset
}

function set_boundary_prevents_y() {
  instruction1.style.color = 'red';
  instruction1.style.fontWeight = 'bold';
  container.style.overscrollBehaviorX = 'auto';
  container.style.overscrollBehaviorY = 'none';
  setUpForRoot(100);
  setUpForContainer(0);
  window.scrollTo(0, 0);
}

function verify_y_prevented_and_set_boundary_prevents_x() {
  instruction1.style.fontWeight = 'normal';
  instruction2.style.fontWeight = 'bold';
  test.step(function() {
    assert_equals(root.scrollTop, 100, "overscroll-behavior-y: none should prevent scroll propagation on y axis.");
    assert_equals(root.scrollLeft, 0, "overscroll-behavior-y: none should only prevent scroll propagation on y axis.");
    window.scrollTo(0, 0);
  });

  container.style.overscrollBehaviorX = 'none';
  container.style.overscrollBehaviorY = 'auto';
  setUpForRoot(100);
  setUpForContainer(0);
  window.scrollTo(0, 0);
}

function verify_x_prevented_and_set_boundary_allows_inner() {
  instruction2.style.fontWeight = 'normal';
  instruction3.style.fontWeight = 'bold';
  test.step(function() {
    assert_equals(root.scrollTop, 0, "overscroll-behavior-x: none should only prevent scroll propagation on x axis.");
    assert_equals(root.scrollLeft, 100, "overscroll-behavior-x: none should prevent scroll propagation on x axis." );
  });

  container.style.overscrollBehaviorX = 'none';
  container.style.overscrollBehaviorY = 'none';
  setUpForRoot(100);
  setUpForContainer(100);
  window.scrollTo(0, 0);
}

function verify_inner_allowed_and_set_nonscrollable_allows_propagation() {
  instruction1.style.color = 'black';
  instruction4.style.color = 'red';
  instruction3.style.fontWeight = 'normal';
  instruction4.style.fontWeight = 'bold';
  test.step(function() {
    assert_equals(container.scrollTop, 0, "overscroll-behavior should latch the scroll to the inner container.");
    assert_equals(container.scrollLeft, 0, "overscroll-behavior should latch the scroll to the inner container.");
    assert_equals(root.scrollTop, 100, "overscroll-behavior should latch the scroll to the inner container.");
    assert_equals(root.scrollLeft, 100, "overscroll-behavior should latch the scroll to the inner container.");
  });

  non_scrollable.style.overscrollBehaviorX = 'none';
  non_scrollable.style.overscrollBehaviorY = 'none';
  setUpForRoot(100);
  window.scrollTo(0, 0);
}

function verify_non_scrollable_allows_propagation() {
  test.step(function() {
    assert_equals(root.scrollLeft, 0, "overscroll-behavior on non-scrollable area should not affect scroll propagation.");
    assert_equals(root.scrollTop, 0, "overscroll-behavior on non-scrollable area should not affect scroll propagation.");
  });
  actions_promise.then( () => {
    test.done();
  });
}

var verifyAndSetupForNext = [
    set_boundary_prevents_y,
    verify_y_prevented_and_set_boundary_prevents_x,
    verify_x_prevented_and_set_boundary_allows_inner,
    verify_inner_allowed_and_set_nonscrollable_allows_propagation,
    verify_non_scrollable_allows_propagation];

on_event(btnDone, "click", function() {
  if (current_test < verifyAndSetupForNext.length)
    verifyAndSetupForNext[current_test++]();
});

var current_test = 0;
verifyAndSetupForNext[current_test++]();

// Inject scroll actions.
const test_cases = [
  { x: 200, y: 500, dx: -200, dy: -200 },
  { x: 200, y: 500, dx: -200, dy: -200 },
  { x: 200, y: 500, dx: -200, dy: -200 },
  { x: 200, y: 100, dx: -200, dy: -200 },
];

actions_promise = new Promise( (resolve) => {resolve();} );
for (let action of test_cases) {
  actions_promise = actions_promise.then(() => {
    return smoothScrollByXY(action.x, action.y, 0, action.dy);
  }).then(() => {
    return waitForAnimationEnd(scrollTop);
  }).then(() => {
    return smoothScrollByXY(action.x, action.y, action.dx, 0);
  }).then(() => {
    return waitForAnimationEnd(scrollLeft);
  }).then(() => {
    return test_driver.click(btnDone);
  });
}

</script>