it("should insert a new atribute with an empty value before the existing valueless attribute", function () {
                testDocument.replaceRange("  <input checked>\n", { line: 9, ch: 0 });  // insert new line

                testEditor.setCursorPos({ line: 9, ch: 9 });    // cursor after trailing space
                selectHint(HTMLCodeHints.attrHintProvider, "class");