Blitz - WPT: layer.html

wpt / css / css-cascade / parsing / layer.html

Data from commit:
a50cb89 wpt: run reference-named files which are themselves tests (#836) (2026-09-03)

Subtest	Status	Message
@layer A; should be a valid rule	FAIL	Cannot destructure 'undefined' value
@layer A, B, C; should be a valid rule	FAIL	Cannot destructure 'undefined' value
@layer A.A; should be a valid rule	FAIL	Cannot destructure 'undefined' value
@layer A, B.C.D, C; should be a valid rule	FAIL	Cannot destructure 'undefined' value
@layer; should be an invalid rule	FAIL	assert_throws_dom: @layer; should throw in insertRule function "() => sheet.insertRule(rule)" threw object "TypeError: cannot convert 'null' or 'undefined' to object" that is not a DOMException 12: property "code" is equal to undefined, expected 12
@layer A . A; should be an invalid rule	FAIL	assert_throws_dom: @layer A . A; should throw in insertRule function "() => sheet.insertRule(rule)" threw object "TypeError: cannot convert 'null' or 'undefined' to object" that is not a DOMException 12: property "code" is equal to undefined, expected 12
@layer { } should be a valid rule	FAIL	Cannot destructure 'undefined' value
@layer A { } should be a valid rule	FAIL	Cannot destructure 'undefined' value
@layer A.B { } should be a valid rule	FAIL	Cannot destructure 'undefined' value
@layer A . B { } should be an invalid rule	FAIL	assert_throws_dom: @layer A . B { } should throw in insertRule function "() => sheet.insertRule(rule)" threw object "TypeError: cannot convert 'null' or 'undefined' to object" that is not a DOMException 12: property "code" is equal to undefined, expected 12
@layer A, B, C { } should be an invalid rule	FAIL	assert_throws_dom: @layer A, B, C { } should throw in insertRule function "() => sheet.insertRule(rule)" threw object "TypeError: cannot convert 'null' or 'undefined' to object" that is not a DOMException 12: property "code" is equal to undefined, expected 12

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/css/css-cascade/parsing/layer.html

<!doctype html>
<meta charset="utf-8">
<title>@layer rule parsing / serialization</title>
<link rel="author" title="Emilio Cobos Álvarez" href="mailto:emilio@crisal.io">
<link rel="author" title="Mozilla" href="https://mozilla.org">
<link rel="help" href="https://drafts.csswg.org/css-cascade-5/#layering">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/css/support/parsing-testcommon.js"></script>
<script>
  test_valid_rule("@layer A;");
  test_valid_rule("@layer A, B, C;");
  test_valid_rule("@layer A.A;");
  test_valid_rule("@layer A, B.C.D, C;");

  test_invalid_rule("@layer;");
  test_invalid_rule("@layer A . A;");

  test_valid_rule("@layer {\n}");
  test_valid_rule("@layer A {\n}");
  test_valid_rule("@layer A.B {\n}");
  test_invalid_rule("@layer A . B {\n}");

  test_invalid_rule("@layer A, B, C {\n}");
</script>