chromium/third_party/blink/web_tests/external/wpt/css/css-scroll-snap/unreachable-snap-positions-002.html

<!DOCTYPE html>
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="help" href="https://drafts.csswg.org/css-scroll-snap/#unreachable" />
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<style>
.scroller {
  width: 100vw;
  height: 100px;
  display: flex;
  scroll-snap-type: x mandatory;
  overflow-x: auto;
}
.scroller.rtl {
  direction: rtl;
}
.scroller.end > span {
  scroll-snap-align: end;
}
.scroller.center > span {
  scroll-snap-align: end;
}
</style>
<div class="scroller end">
  <span style="min-width:  25px;"></span>
  <span style="min-width: 100vw;"></span>
</div>
<div class="scroller center">
  <span style="min-width:  25px;"></span>
  <span style="min-width: 100vw;"></span>
</div>
<div class="scroller end rtl">
  <span style="min-width:  25px;"></span>
  <span style="min-width: 100vw;"></span>
</div>
<div class="scroller center rtl">
  <span style="min-width:  25px;"></span>
  <span style="min-width: 100vw;"></span>
</div>
<script>

test(() => {
  const scroller = document.querySelector(".scroller.end");
  assert_equals(scroller.scrollLeft, 0);
  assert_equals(scroller.scrollTop, 0);
}, "Unreachable snap point with `scroll-snap-align: end`");

test(() => {
  const scroller = document.querySelector(".scroller.center");
  assert_equals(scroller.scrollLeft, 0);
  assert_equals(scroller.scrollTop, 0);
}, "Unreachable snap point with `scroll-snap-align: center`");

test(() => {
  const scroller = document.querySelector(".scroller.end.rtl");
  assert_equals(scroller.scrollLeft, 0);
  assert_equals(scroller.scrollTop, 0);
}, "Unreachable snap point with `scroll-snap-align: end` in RTL");

test(() => {
  const scroller = document.querySelector(".scroller.center.rtl");
  assert_equals(scroller.scrollLeft, 0);
  assert_equals(scroller.scrollTop, 0);
}, "Unreachable snap point with `scroll-snap-align: center` in RTL");

</script>
</html>