selector_checker.h | Explore in Territory

/*
 * Copyright (C) 1999 Lars Knoll ([email protected])
 *           (C) 2004-2005 Allan Sandfeld Jensen ([email protected])
 * Copyright (C) 2006, 2007 Nicholas Shanks ([email protected])
 * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 Apple Inc.
 * All rights reserved.
 * Copyright (C) 2007 Alexey Proskuryakov <[email protected]>
 * Copyright (C) 2007, 2008 Eric Seidel <[email protected]>
 * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved.
 * (http://www.torchmobile.com/)
 * Copyright (c) 2011, Code Aurora Forum. All rights reserved.
 * Copyright (C) Research In Motion Limited 2011. All rights reserved.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public License
 * along with this library; see the file COPYING.LIB.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301, USA.
 */

#ifndef THIRD_PARTY_BLINK_RENDERER_CORE_CSS_SELECTOR_CHECKER_H_
#define THIRD_PARTY_BLINK_RENDERER_CORE_CSS_SELECTOR_CHECKER_H_

#include <limits>
#include "base/dcheck_is_on.h"
#include "third_party/blink/renderer/core/core_export.h"
#include "third_party/blink/renderer/core/css/css_selector.h"
#include "third_party/blink/renderer/core/css/resolver/match_flags.h"
#include "third_party/blink/renderer/core/css/style_request.h"
#include "third_party/blink/renderer/core/css/style_scope.h"
#include "third_party/blink/renderer/core/css/style_scope_frame.h"
#include "third_party/blink/renderer/core/dom/element.h"
#include "third_party/blink/renderer/core/scroll/scroll_types.h"
#include "third_party/blink/renderer/platform/heap/collection_support/heap_hash_map.h"
#include "third_party/blink/renderer/platform/heap/collection_support/heap_vector.h"
#include "third_party/blink/renderer/platform/heap/garbage_collected.h"
#include "third_party/blink/renderer/platform/heap/member.h"
#include "third_party/blink/renderer/platform/heap/visitor.h"

namespace blink {

class CSSSelector;
class ContainerNode;
class CustomScrollbar;
class Element;
class PartNames;

class CORE_EXPORT SelectorChecker { … };

// An accelerated selector checker that matches only selectors with a
// certain set of restrictions, informally called “easy” selectors.
// (Not to be confused with simple selectors, which is a standards-defined
// term.) Easy selectors support only a very small subset of the full
// CSS selector machinery, but does so much faster than SelectorChecker
// (typically a bit over twice as fast), and that subset tends to be enough
// for ~80% of actual selectors checks on a typical web page. (It is also
// ree from the complexities of Shadow DOM and does not check whether
// the query exceeds the scope, so it cannot be used for querySelector().)
//
// The set of supported selectors is formally given as “anything IsEasy()
// returns true for”, but roughly encompasses the following:
//
//  - Tag matches (e.g. div).
//  - ID matches (e.g. #id).
//  - Class matches (e.g. .c).
//  - Case-sensitive attribute is-set and exact matches ([foo] and [foo="bar"]).
//  - Subselector and descendant combinators.
//  - Anything that does not need further checking
//    (CSSSelector::IsCoveredByBucketing()).
//
// Given this, it does not need to set up any context, do recursion,
// backtracking, have large switch/cases for pseudos, or the similar.
//
// You must include selector_checker-inl.h to use this class;
// its functions are declared ALWAYS_INLINE because the call overhead
// is so large compared to what the functions are actually doing.
class CORE_EXPORT EasySelectorChecker { … };

}  // namespace blink

#endif  // THIRD_PARTY_BLINK_RENDERER_CORE_CSS_SELECTOR_CHECKER_H_
chromium/third_party/blink/renderer/core/css/selector_checker.h
