LibWeb: Add the type field to DOM::Document

This patch adds the document type concept to documents and sets it in
various places.

Userland/Libraries/LibWeb/DOM/DOMImplementation.cpp

@@ -53,7 +53,6 @@ ExceptionOr<NonnullRefPtr<Document>> DOMImplementation::create_document(String c
 // https://dom.spec.whatwg.org/#dom-domimplementation-createhtmldocument
 NonnullRefPtr<Document> DOMImplementation::create_html_document(String const& title) const
 {
-    // FIXME: This should specifically be a HTML document.
     auto html_document = Document::create();
 
     html_document->set_content_type("text/html");

Userland/Libraries/LibWeb/DOM/Document.h

@@ -45,6 +45,11 @@ class Document
 public:
     using WrapperType = Bindings::DocumentWrapper;
 
+    enum class Type {
+        XML,
+        HTML
+    };
+
     static NonnullRefPtr<Document> create(const AK::URL& url = "about:blank")
     {
         return adopt_ref(*new Document(url));
@@ -208,6 +213,12 @@ public:
     bool in_quirks_mode() const { return m_quirks_mode == QuirksMode::Yes; }
     void set_quirks_mode(QuirksMode mode) { m_quirks_mode = mode; }
 
+    Type document_type() const { return m_type; }
+    void set_document_type(Type type) { m_type = type; }
+
+    // https://dom.spec.whatwg.org/#xml-document
+    bool is_xml_document() const { return m_type == Type::XML; }
+
     ExceptionOr<NonnullRefPtr<Node>> import_node(NonnullRefPtr<Node> node, bool deep);
     void adopt_node(Node&);
     ExceptionOr<NonnullRefPtr<Node>> adopt_node_binding(NonnullRefPtr<Node>);
@@ -411,6 +422,10 @@ private:
     NonnullRefPtrVector<HTML::HTMLScriptElement> m_scripts_to_execute_as_soon_as_possible;
 
     QuirksMode m_quirks_mode { QuirksMode::No };
+
+    // https://dom.spec.whatwg.org/#concept-document-type
+    Type m_type { Type::HTML };
+
     bool m_editable { false };
 
     WeakPtr<Element> m_focused_element;

Userland/Libraries/LibWeb/DOM/Node.cpp

@@ -680,7 +680,7 @@ NonnullRefPtr<Node> Node::clone_node(Document* document, bool clone_children)
         document_copy->set_content_type(document_->content_type());
         document_copy->set_url(document_->url());
         document_copy->set_origin(document_->origin());
-        // FIXME: Set type ("xml" or "html")
+        document_copy->set_document_type(document_->document_type());
         document_copy->set_quirks_mode(document_->mode());
         copy = move(document_copy);
     } else if (is<DocumentType>(this)) {

Userland/Libraries/LibWeb/HTML/DOMParser.cpp

@@ -25,7 +25,8 @@ NonnullRefPtr<DOM::Document> DOMParser::parse_from_string(String const& string,
     // 2. Switch on type:
     if (type == Bindings::DOMParserSupportedType::Text_Html) {
         // -> "text/html"
-        // FIXME: 1. Set document's type to "html".
+        // 1. Set document's type to "html".
+        document->set_document_type(DOM::Document::Type::HTML);
 
         // 2. Create an HTML parser parser, associated with document.
         // 3. Place string into the input stream for parser. The encoding confidence is irrelevant.

Userland/Libraries/LibWeb/HTML/HTMLTemplateElement.cpp

@@ -24,8 +24,7 @@ DOM::Document& HTMLTemplateElement::appropriate_template_contents_owner_document
         if (!document.associated_inert_template_document()) {
             auto new_document = DOM::Document::create();
             new_document->set_created_for_appropriate_template_contents(true);
-
-            // FIXME: If doc is an HTML document, mark new doc as an HTML document also.
+            new_document->set_document_type(document.document_type());
 
             document.set_associated_inert_template_document(new_document);
         }