Moved MQ parsing block tracking to tokenizer

Source/core/css/parser/MediaQueryTokenizer.cpp

Index: Source/core/css/parser/MediaQueryTokenizer.cpp
diff --git a/Source/core/css/parser/MediaQueryTokenizer.cpp b/Source/core/css/parser/MediaQueryTokenizer.cpp
index 469221d5252f011d894a9ece53292ef33c08fe02..7579b969432b2ac70a4f33d3f22a1bf533aa1f08 100644
--- a/Source/core/css/parser/MediaQueryTokenizer.cpp
+++ b/Source/core/css/parser/MediaQueryTokenizer.cpp
@@ -67,34 +67,62 @@ MediaQueryToken MediaQueryTokenizer::whiteSpace(UChar cc)
     return MediaQueryToken(WhitespaceToken);
 }
 
+static bool popIfBlockMatches(Vector<MediaQueryTokenType>& blockStack, MediaQueryTokenType type)
+{
+    if (!blockStack.isEmpty() && blockStack.last() == type) {
+        blockStack.removeLast();
+        return true;
+    }
+    return false;
+}
+
+MediaQueryToken MediaQueryTokenizer::blockStart(MediaQueryTokenType type)
+{
+    m_blockStack.append(type);
+    return MediaQueryToken(type, MediaQueryToken::BlockStart);
+}
+
+MediaQueryToken MediaQueryTokenizer::blockStart(MediaQueryTokenType blockType, MediaQueryTokenType type, String name)
+{
+    m_blockStack.append(blockType);
+    return MediaQueryToken(type, name, MediaQueryToken::BlockStart);
+}
+
+MediaQueryToken MediaQueryTokenizer::blockEnd(MediaQueryTokenType type, MediaQueryTokenType startType)
+{
+    if (popIfBlockMatches(m_blockStack, startType))
+        return MediaQueryToken(type, MediaQueryToken::BlockEnd);
+    return MediaQueryToken(type);
+}
+
 MediaQueryToken MediaQueryTokenizer::leftParenthesis(UChar cc)
 {
-    return MediaQueryToken(LeftParenthesisToken);
+    return blockStart(LeftParenthesisToken);
 }
 
 MediaQueryToken MediaQueryTokenizer::rightParenthesis(UChar cc)
 {
-    return MediaQueryToken(RightParenthesisToken);
+    return blockEnd(RightParenthesisToken, LeftParenthesisToken);
 }
 
 MediaQueryToken MediaQueryTokenizer::leftBracket(UChar cc)
 {
-    return MediaQueryToken(LeftBracketToken);
+    return blockStart(LeftBracketToken);
 }
 
 MediaQueryToken MediaQueryTokenizer::rightBracket(UChar cc)
 {
-    return MediaQueryToken(RightBracketToken);
+    return blockEnd(RightBracketToken, LeftBracketToken);
 }
 
 MediaQueryToken MediaQueryTokenizer::leftBrace(UChar cc)
 {
-    return MediaQueryToken(LeftBraceToken);
+    return blockStart(LeftBraceToken);
 }
 
 MediaQueryToken MediaQueryTokenizer::rightBrace(UChar cc)
 {
-    return MediaQueryToken(RightBraceToken);
+    return blockEnd(RightBraceToken, LeftBraceToken);
 }
 
 MediaQueryToken MediaQueryTokenizer::plusOrFullStop(UChar cc)
@@ -189,6 +217,7 @@ void MediaQueryTokenizer::tokenize(String string, Vector<MediaQueryToken>& outTo
     MediaQueryTokenizer tokenizer(input);
     while (true) {
         MediaQueryToken token = tokenizer.nextToken();
+        token.setBlockLevel(tokenizer.m_blockStack.size());

[eseidel, 2014/04/08 22:58:51]

I see.  Because the parser doesn't know how to maintain the block level anymore,
we have to set the block level on every token, ouch.

this is all to share code between two possible parsers who both want to watch
block level?  Should we instead do this by having a parser superclass, or a
tokenizer driver which both parser use to drive the tokenizer?

         outTokens.append(token);
         if (token.type() == EOFToken)
             return;
@@ -216,7 +245,6 @@ MediaQueryToken MediaQueryTokenizer::nextToken()
 
     if (codePointFunc)
         return ((this)->*(codePointFunc))(cc);
-
     return MediaQueryToken(DelimiterToken, cc);
 }
 
@@ -315,8 +343,9 @@ MediaQueryToken MediaQueryTokenizer::consumeNumericToken()
 MediaQueryToken MediaQueryTokenizer::consumeIdentLikeToken()
 {
     String name = consumeName();
-    if (consumeIfNext('('))
-        return MediaQueryToken(FunctionToken, name);
+    if (consumeIfNext('(')) {
+        return blockStart(LeftParenthesisToken, FunctionToken, name);
+    }
     return MediaQueryToken(IdentToken, name);
 }