CSS Parser: Implement selector parsing [1/3]

Source/core/css/parser/CSSSelectorParser.h

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CSSSelectorParser_h
+#define CSSSelectorParser_h
+
+#include "core/css/parser/CSSParserTokenRange.h"
+#include "core/css/parser/CSSParserValues.h"
+
+namespace blink {
+
+class CSSSelectorList;
+class StyleSheetContents;
+
+// FIXME: We should consider building CSSSelectors directly instead of using
+// the intermediate CSSParserSelector.
+class CSSSelectorParser {
+public:
+    static void parseSelector(CSSParserTokenRange, const CSSParserContext&, CSSSelectorList&);
+
+private:
+    CSSSelectorParser(CSSParserTokenRange, const CSSParserContext&);
+
+    // These will all consume trailing comments if successful
+
+    void consumeComplexSelectorList(CSSSelectorList&);
+
+    PassOwnPtr<CSSParserSelector> consumeComplexSelector();
+    PassOwnPtr<CSSParserSelector> consumeCompoundSelector();
+    // This doesn't include element names, since they're handled specially
+    PassOwnPtr<CSSParserSelector> consumeSimpleSelector();
+
+    bool consumeName(AtomicString& name, AtomicString& namespacePrefix, bool& hasNamespace);
+
+    // These will return nullptr when the selector is invalid
+    PassOwnPtr<CSSParserSelector> consumeId();
+    PassOwnPtr<CSSParserSelector> consumeClass();
+    PassOwnPtr<CSSParserSelector> consumePseudo();
+    PassOwnPtr<CSSParserSelector> consumeAttribute();
+
+    CSSSelector::Relation consumeCombinator();
+
+    QualifiedName determineNameInNamespace(const AtomicString& prefix, const AtomicString& localName);
+    void rewriteSpecifiersWithNamespaceIfNeeded(CSSParserSelector*);
+    void rewriteSpecifiersWithElementName(const AtomicString& namespacePrefix, const AtomicString& elementName, CSSParserSelector*, bool tagIsForNamespaceRule = false);
+    void rewriteSpecifiersWithElementNameForCustomPseudoElement(const QualifiedName& tag, const AtomicString& elementName, CSSParserSelector*, bool tagIsForNamespaceRule);
+    void rewriteSpecifiersWithElementNameForContentPseudoElement(const QualifiedName& tag, const AtomicString& elementName, CSSParserSelector*, bool tagIsForNamespaceRule);
+    PassOwnPtr<CSSParserSelector> rewriteSpecifiers(PassOwnPtr<CSSParserSelector> specifiers, PassOwnPtr<CSSParserSelector> newSpecifier);
+
+    CSSParserTokenRange m_tokenRange;
+
+    const CSSParserContext& m_context;
+    AtomicString m_defaultNamespace;
+    StyleSheetContents* m_styleSheet;
+
+    bool m_failedParsing;
+};
+
+} // namespace
+
+#endif // CSSSelectorParser_h