FAIL document.adoptedStyleSheets should initially have length 0. undefined is not an object (evaluating 'document.adoptedStyleSheets.length')
FAIL new CSSStyleSheet produces empty CSSStyleSheet Illegal constructor
FAIL title can be set in the CSSStyleSheet constructor Illegal constructor
FAIL CSSStyleSheet.replace produces Promise<CSSStyleSheet> Illegal constructor
FAIL Constructed style sheets can be applied on document Illegal constructor
FAIL Constructed style sheets can be applied on shadow root Illegal constructor
FAIL Re-attaching shadow host with adopted stylesheets work Illegal constructor
FAIL Attaching a shadow root that already has adopted stylesheets work Illegal constructor
FAIL Re-attaching shadow host and updating attributes work Illegal constructor
FAIL Changes to constructed stylesheets through CSSOM is reflected Illegal constructor
FAIL Constructed stylesheet can be used and modified in multiple TreeScopes Illegal constructor
FAIL Stylesheets constructed on the main Document cannot be used in iframes Illegal constructor
FAIL Stylesheet constructed on iframe cannot be used in the main Document promise_test: Unhandled rejection with value: object "TypeError: Illegal constructor"
FAIL Adding non-constructed stylesheet to AdoptedStyleSheets is not allowed when the owner document of the stylesheet is in the same document tree as the AdoptedStyleSheets assert_throws_dom: function "() => { document.adoptedStyleSheets = [nonConstructedStyleSheet]; }" did not throw
FAIL Adding non-constructed stylesheet to AdoptedStyleSheets is not allowed when the owner document of the stylesheet and the AdoptedStyleSheets are in different document trees assert_throws_dom: function "() => {
    iframe.contentDocument.adoptedStyleSheets = [nonConstructedStyleSheet];
  }" did not throw
FAIL CSSStyleSheet.replaceSync replaces stylesheet text synchronously Illegal constructor
FAIL CSSStyleSheet.replaceSync correctly updates the style of its adopters synchronously Illegal constructor
FAIL Adopted sheets are ordered after non-adopted sheets in the shadow root Illegal constructor
FAIL Adopted sheets are ordered after non-adopted sheets in the document Illegal constructor
FAIL Inserting an @import rule through insertRule on a constructed stylesheet throws an exception assert_throws_dom: function "() => { (new CSSStyleSheet).insertRule(import_text) }" threw object "TypeError: Illegal constructor" that is not a DOMException SyntaxError: property "code" is equal to undefined, expected 12
FAIL CSSStyleSheet.replaceSync should not trigger any loads from @import rules Illegal constructor
FAIL CSSStyleSheet.replace allows, but ignores, import rule inside Illegal constructor
FAIL CSSStyleSheet.replace ignores @import rule but still loads other rules Illegal constructor
FAIL CSSStyleSheet.replaceSync allows, but ignores, import rule inside Illegal constructor
FAIL CSSStyleSheet.replace does not reject on failed imports Illegal constructor
FAIL Cloning a shadow host will not clone shadow root, and also adoptedStyleSheets Illegal constructor
FAIL Importing a shadow host will not copy shadow root, and also adoptedStyleSheets Illegal constructor
FAIL Adopting a shadow host will empty adoptedStyleSheets if adopting to a different document Illegal constructor
FAIL Adopting a shadow host's ancestor will empty adoptedStyleSheets if adopting to a different document Illegal constructor
FAIL Forcing a style update after adding an adopted stylesheet on a disconnected shadow root should not crash. Illegal constructor
FAIL Modifying an adopted stylesheet on a disconnected shadow root should not crash. Illegal constructor
FAIL Constructing a sheet with the default base URL uses the constructor document's base URL for CSS rules Illegal constructor