chromium/third_party/blink/web_tests/external/wpt/css/css-grid/parsing/grid-template-areas-one-cell.html

<!doctype html>
<title>grid-template-areas must define at least one cell</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<link rel=author title="Tab Atkins-Bittner" href="https://www.xanthir.com/contact/">
<link rel=help href="https://www.w3.org/TR/css-grid-1/#grid-template-areas-property">
<meta name=assert content="grid-template-areas must define at least one cell to be valid.">

<script>
function testValidGta(val) {
  test(()=>{
    const root = document.children[0];
    root.style.gridTemplateAreas = "";
    root.style.gridTemplateAreas = val;
    assert_not_equals(root.style.gridTemplateAreas, "");
  }, `"grid-template-areas: ${val};" should be valid.`);
}
function testInvalidGta(val) {
  test(()=>{
    const root = document.children[0];
    root.style.gridTemplateAreas = "";
    root.style.gridTemplateAreas = val;
    assert_equals(root.style.gridTemplateAreas, "");
  }, `"grid-template-areas: ${val};" should be invalid.`);
}

testValidGta("'a'");
testValidGta("'.'");

testInvalidGta("''");
testInvalidGta("'' ''");
testInvalidGta("'$'");
testInvalidGta("'  '");
</script>