Make WebNode::to<Type>() (and toConst) casts contain type asserts.

third_party/WebKit/public/web/WebNode.h

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 57 matching lines @@
     BLINK_EXPORT void reset();
     BLINK_EXPORT void assign(const WebNode&);
 
     BLINK_EXPORT bool equals(const WebNode&) const;
     // Required for using WebNodes in std maps.  Note the order used is
     // arbitrary and should not be expected to have any specific meaning.
     BLINK_EXPORT bool lessThan(const WebNode&) const;
 
     bool isNull() const { return m_private.isNull(); }
 
-    enum NodeType {
-        ElementNode = 1,
-        AttributeNode = 2,
-        TextNode = 3,
-        CDataSectionNode = 4,
-        // EntityReferenceNodes are impossible to create in Blink.
-        // EntityNodes are impossible to create in Blink.
-        ProcessingInstructionsNode = 7,
-        CommentNode = 8,
-        DocumentNode = 9,
-        DocumentTypeNode = 10,
-        DocumentFragmentNode = 11,
-        // NotationNodes are impossible to create in Blink.
-        // XPathNamespaceNodes are impossible to create in Blink.
-        ShadowRootNode = 14
-    };
-
-    BLINK_EXPORT NodeType nodeType() const;
     BLINK_EXPORT WebNode parentNode() const;
     BLINK_EXPORT WebString nodeValue() const;
     BLINK_EXPORT WebDocument document() const;
     BLINK_EXPORT WebNode firstChild() const;
     BLINK_EXPORT WebNode lastChild() const;
     BLINK_EXPORT WebNode previousSibling() const;
     BLINK_EXPORT WebNode nextSibling() const;
     BLINK_EXPORT bool hasChildNodes() const;
     BLINK_EXPORT WebNodeList childNodes();
     BLINK_EXPORT bool isLink() const;
+    BLINK_EXPORT bool isDocumentNode() const;
     BLINK_EXPORT bool isCommentNode() const;
     BLINK_EXPORT bool isTextNode() const;
     BLINK_EXPORT bool isFocusable() const;
     BLINK_EXPORT bool isContentEditable() const;
     BLINK_EXPORT bool isElementNode() const;
     BLINK_EXPORT void dispatchEvent(const WebDOMEvent&);
     BLINK_EXPORT void simulateClick();
     // The argument should be lower-cased.
     BLINK_EXPORT WebElementCollection getElementsByHTMLTagName(const WebString&) const;
 
 
     BLINK_EXPORT WebElement querySelector(const WebString& selector, WebExceptionCode&) const;
     BLINK_EXPORT void querySelectorAll(const WebString& selector, WebVector<WebElement>& results, WebExceptionCode&) const;
 
     // Same as querySelector and querySelectorAll, but ASSERT if an exception
     // code would be generated.
     BLINK_EXPORT WebElement querySelector(const WebString& selector) const;
     BLINK_EXPORT void querySelectorAll(const WebString& selector, WebVector<WebElement>& results) const;
 
     BLINK_EXPORT bool focused() const;
 
     BLINK_EXPORT WebPluginContainer* pluginContainer() const;
 
     BLINK_EXPORT bool isInsideFocusableElementOrARIAWidget() const;
     BLINK_EXPORT WebAXObject accessibilityObject();
 
-    template<typename T> T to()
-    {
-        T res;
-        res.WebNode::assign(*this);
-        return res;
-    }
-
-    template<typename T> const T toConst() const
-    {
-        T res;
-        res.WebNode::assign(*this);
-        return res;
-    }
+    template<typename T> T to();
+    template<typename T> const T toConst() const;
 
 #if BLINK_IMPLEMENTATION
     WebNode(const PassRefPtrWillBeRawPtr<Node>&);
     WebNode& operator=(const PassRefPtrWillBeRawPtr<Node>&);
     operator PassRefPtrWillBeRawPtr<Node>() const;
-#endif
 
-#if BLINK_IMPLEMENTATION
     template<typename T> T* unwrap()
     {
         return static_cast<T*>(m_private.get());
     }
 
     template<typename T> const T* constUnwrap() const
     {
         return static_cast<const T*>(m_private.get());
     }
 #endif
 
 protected:
     WebPrivatePtr<Node> m_private;
 };
 
+#define DECLARE_WEB_NODE_TYPE_CASTS(type) \
+template<> \
+BLINK_EXPORT type WebNode::to<type>(); \
+template<> \
+BLINK_EXPORT const type WebNode::toConst<type>() const;
+
+#if BLINK_IMPLEMENTATION
+#define DEFINE_WEB_NODE_TYPE_CASTS(type, predicate) \
+template<> \
+type WebNode::to<type>() { \
+    ASSERT_WITH_SECURITY_IMPLICATION(isNull() || (predicate)); \
+    type result; \
+    result.WebNode::assign(*this); \
+    return result; \
+} \
+template<> \
+const type WebNode::toConst<type>() const { \
+    ASSERT_WITH_SECURITY_IMPLICATION(isNull() || (predicate)); \
+    type result; \
+    result.WebNode::assign(*this); \
+    return result; \
+}
+#endif
+
 inline bool operator==(const WebNode& a, const WebNode& b)
 {
     return a.equals(b);
 }
 
 inline bool operator!=(const WebNode& a, const WebNode& b)
 {
     return !(a == b);
 }
 
 inline bool operator<(const WebNode& a, const WebNode& b)
 {
     return a.lessThan(b);
 }
 
 } // namespace blink
 
 #endif