chromium/third_party/blink/web_tests/editing/caret/empty_editables.html

<!doctype html>
<script src="../../resources/ahem.js"></script>
<script src="../../resources/testharness.js"></script>
<script src="../../resources/testharnessreport.js"></script>
<script src="../assert_selection.js"></script>
<script>
const kLineHeight = 20;
const kStyle = `font: 10px/${kLineHeight}px Ahem;`;

function checkHeight(content, expectedHeight = kLineHeight) {
    const sample = [
        `<div contenteditable id="target" style="${kStyle}">|`,
        content,
        '</div>',
    ].join('');

    selection_test(
        sample,
        selection => {
            const target = selection.document.getElementById('target');
            assert_equals(target.offsetHeight, expectedHeight);
        },
        sample,
        `Height of <editable>${content}</editable> is ${expectedHeight}px.`);
}


checkHeight('');
checkHeight('<div></div>', 0);
checkHeight('<div style="display:inline-block"></div>', 0);
checkHeight('<div style="display:inline-block; height: 10px;"></div>', 10);
checkHeight('<div style="float:left"></div>');
checkHeight('<div style="float:left">x</div>');
checkHeight('<div style="position:absolute"></div>');
checkHeight('<div style="position:absolute">x</div>');
checkHeight('<div style="position:relative"></div>', 0);
checkHeight('<div style="position:relative">x</div>');

checkHeight('<span></span>');
checkHeight('<span style="display:inline-block"></span>', 0);
checkHeight('<span style="display:inline-block; height: 10px;"></span>', 10);
checkHeight('<span style="float:left"></span>');
checkHeight('<span style="float:left">x</span>');
checkHeight('<span style="position:absolute"></span>');
checkHeight('<span style="position:absolute">x</span>');
checkHeight('<span style="position:relative"></span>');
checkHeight('<span style="position:relative">x</span>');
</script>