css/css-cascade/idlharness.html

<!doctype html>
<title>CSS Cascade Layers IDL tests</title>
<link rel="help" href="https://drafts.csswg.org/css-cascade-5/#layer-apis">
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/resources/WebIDLParser.js"></script>
<script src="/resources/idlharness.js"></script>

<style>
@layer bar, baz;
@import url('data:text/css,') layer(qux);
@layer foo { }
</style>

<script>
  'use strict';
  idl_test(
    ['css-cascade'],
    ['cssom'],
    idl_array => {
      try {
        self.statement = document.styleSheets[0].cssRules.item(0);
        self.layeredImport = document.styleSheets[0].cssRules.item(1);
        self.block = document.styleSheets[0].cssRules.item(2);
      } catch (e) {
        // Will be surfaced when any rule is undefined below.
      }

      idl_array.add_objects({
        CSSLayerBlockRule: ['block'],
        CSSLayerStatementRule: ['statement'],
        CSSImportRule: ['layeredImport']
      });
    }
  );
</script>