Test cases for querySelector fast paths.

third_party/WebKit/Source/core/dom/SelectorQuery.h

 /*
  * Copyright (C) 2011, 2013 Apple Inc. All rights reserved.
  * Copyright (C) 2014 Samsung Electronics. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
@@ skipping 46 matching lines @@
 
   // https://dom.spec.whatwg.org/#dom-element-closest
   Element* closest(Element&) const;
 
   // https://dom.spec.whatwg.org/#dom-parentnode-queryselectorall
   StaticElementList* queryAll(ContainerNode& rootNode) const;
 
   // https://dom.spec.whatwg.org/#dom-parentnode-queryselector
   Element* queryFirst(ContainerNode& rootNode) const;
 
+  struct QueryStats {
+    unsigned totalCount;
+    unsigned fastId;
+    unsigned fastClass;
+    unsigned fastTagName;
+    unsigned fastScan;
+    unsigned slowScan;
+    unsigned slowTraversingShadowTreeScan;
+  };
+  // Used by unit tests to get information about what paths were taken during
+  // the last query. Always reset between queries. This system is disabled in
+  // non DCHECK builds to avoid the overhead on the query process.
+  static QueryStats lastQueryStats();
+
  private:
   explicit SelectorQuery(CSSSelectorList);
 
   bool canUseFastQuery(const ContainerNode& rootNode) const;
 
   template <typename SelectorQueryTrait>
   void findTraverseRootsAndExecute(
       ContainerNode& rootNode,
       typename SelectorQueryTrait::OutputType&) const;
   template <typename SelectorQueryTrait>
@@ skipping 30 matching lines @@
   SelectorQuery* add(const AtomicString&, const Document&, ExceptionState&);
   void invalidate();
 
  private:
   HashMap<AtomicString, std::unique_ptr<SelectorQuery>> m_entries;
 };
 
 }  // namespace blink
 
 #endif