chromium/third_party/blink/web_tests/external/wpt/css/css-anchor-position/try-tactic-basic.html

<!DOCTYPE html>
<title>CSS Anchor Positioning: try-tactic</title>
<link rel="help" href="https://drafts.csswg.org/css-anchor-position-1/#typedef-position-try-fallbacks-try-tactic">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<style>
  @position-try --pf {
    left:10px;
    top:20px;
  }
  #cb {
    position: absolute;
    width: 400px;
    height: 400px;
    border: 1px solid black;
  }
  #target {
    position: absolute;
    left: 99999px; /* force fallback */
    width: 30px;
    height: 40px;
    background-color: skyblue;
  }
</style>
<div id=cb>
  <div id=target></div>
</div>
<script>
  function test_try_tactic(try_tactic, expected_offsets) {
    target.style.positionTryFallbacks = `--pf ${try_tactic}`;
    test(() => {
      assert_equals(target.offsetLeft, expected_offsets.left, 'offsetLeft');
      assert_equals(target.offsetTop, expected_offsets.top, 'offsetTop');
      assert_equals(target.offsetWidth, expected_offsets.width, 'offsetWidth');
      assert_equals(target.offsetHeight, expected_offsets.height, 'offsetHeight');
    }, target.style.positionTryFallbacks);
  }

  test_try_tactic('', {left:10, top:20, width:30, height:40});

  // bottom:20px
  test_try_tactic('flip-block', {left:10, top:340, width:30, height:40});

  // right:10px
  test_try_tactic('flip-inline', {left:360, top:20, width:30, height:40});

  // right:10px; bottom:20px
  test_try_tactic('flip-block flip-inline', {left:360, top:340, width:30, height:40});
  test_try_tactic('flip-inline flip-block', {left:360, top:340, width:30, height:40});

  // left:20px; top:10px; width:40px; height:30px
  test_try_tactic('flip-start', {left:20, top:10, width:40, height:30});
  test_try_tactic('flip-block flip-start flip-inline', {left:20, top:10, width:40, height:30});
  test_try_tactic('flip-inline flip-start flip-block', {left:20, top:10, width:40, height:30});

  // left:20px; bottom:10px; width:40px; height:30px
  test_try_tactic('flip-start flip-block', {left:20, top:360, width:40, height:30});
  test_try_tactic('flip-inline flip-start', {left:20, top:360, width:40, height:30});

  // right:20px; top:10px; width:40px; height:30px
  test_try_tactic('flip-start flip-inline', {left:340, top:10, width:40, height:30});
  test_try_tactic('flip-block flip-start', {left:340, top:10, width:40, height:30});

  // right:20px; bottom:10px; width:40px; height:30px
  test_try_tactic('flip-start flip-block flip-inline', {left:340, top:360, width:40, height:30});
  test_try_tactic('flip-start flip-inline flip-block', {left:340, top:360, width:40, height:30});
  test_try_tactic('flip-inline flip-block flip-start', {left:340, top:360, width:40, height:30});
  test_try_tactic('flip-block flip-inline flip-start', {left:340, top:360, width:40, height:30});
</script>