text: /**
   * Mock objects for browser Document class.
   */
  
  class Element {
  
      constructor() {
          this.lastChild = this;
          this.checked = false;
          this.childNodes = [];
      }
  
      appendChild() {
          return this;
      }
  
      cloneNode() {
          return this;
      }
  
      setAttribute() {
      }
  
      insertBefore() {
      }
  }
  
  class Document {
  
      constructor() {
          this.location = {href: ""}
          this.documentElement = {}
          this.styleSheets = []
          this.head = new Element();
          this.body = new Element();
      }
  
      createDocumentFragment() {
          return new Element();
      }
  
      createElement() {
          return new Element();
      }
  }
  
  class DOMImplementation {
  
      createHTMLDocument() {
          return new Document();
      }
  }
  
  export {Document, DOMImplementation};