Remove scanner abstraction layer from JSON parsing. The change in api.cc is t...

src/json-parser.h

 // Copyright 2011 the V8 project authors. 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
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 29 matching lines @@
     return JsonParser().ParseJson(source);
   }
 
   static const int kEndOfString = -1;
 
  private:
   // Parse a string containing a single JSON value.
   Handle<Object> ParseJson(Handle<String> source);
 
   inline void Advance() {
-    if (position_ >= source_length_) {
-      position_++;
+    position_++;
+    if (position_ > source_length_) {
       c0_ = kEndOfString;
     } else if (is_sequential_ascii_) {

[Lasse Reichstein, 2011/06/01 11:03:58]

This was changed?

[sandholm, 2011/06/01 13:45:20]

r8142 ensures this was not changed.

-      position_++;
       c0_ = seq_source_->SeqAsciiStringGet(position_);
     } else {
-      position_++;
       c0_ = source_->Get(position_);
     }
   }
 
-  inline Isolate* isolate() { return isolate_; }
+  // The JSON lexical grammar is specified in the ECMAScript 5 standard,
+  // section 15.12.1.1. The only allowed whitespace characters between tokens
+  // are tab, carriage-return, newline and space.
 
-  // Get the string for the current string token.
-  Handle<String> GetString(bool hint_symbol);
-  Handle<String> GetString();
-  Handle<String> GetSymbol();
+  inline bool AdvanceWS() {

[Lasse Reichstein, 2011/06/01 11:03:58]

Don't abbreviate unless necessary.
Call this AdvanceSkipWhitespace.

[sandholm, 2011/06/01 13:45:20]

Done.

+    do {
+      Advance();
+    } while (c0_ == '\t' || c0_ == '\r' || c0_ == '\n' || c0_ == ' ');
+    return true;

[Lasse Reichstein, 2011/06/01 11:03:58]

Why the return true? If it always returns the same value, it should be
superfluous.

[sandholm, 2011/06/01 13:45:20]

Done.

+  }
 
-  // Scan a single JSON token. The JSON lexical grammar is specified in the
-  // ECMAScript 5 standard, section 15.12.1.1.
-  // Recognizes all of the single-character tokens directly, or calls a function
-  // to scan a number, string or identifier literal.
-  // The only allowed whitespace characters between tokens are tab,
-  // carriage-return, newline and space.
-  void ScanJson();
+  inline void SkipWS() {

[Lasse Reichstein, 2011/06/01 11:03:58]

And just SkipWhitespace.

[sandholm, 2011/06/01 13:45:20]

Done.

+    while (c0_ == '\t' || c0_ == '\r' || c0_ == '\n' || c0_ == ' ') {
+      Advance();
+    }
+  }
+
+  inline uc32 AdvanceGetChar() {
+    Advance();
+    return c0_;
+  }
 
   // A JSON string (production JSONString) is subset of valid JavaScript string
   // literals. The string must only be double-quoted (not single-quoted), and
   // the only allowed backslash-escapes are ", /, \, b, f, n, r, t and
   // four-digit hex escapes (uXXXX). Any other use of backslashes is invalid.
-  Token::Value ScanJsonString();
+  Handle<Object> ParseJsonString() {
+    return ScanJsonString<false>();
+  }
+  Handle<Object> ParseJsonSymbol() {
+    return ScanJsonString<true>();
+  }
+  template <bool is_symbol>
+  Handle<Object> ScanJsonString();
   // Slow version for unicode support, uses the first ascii_count characters,
   // as first part of a ConsString
-  Token::Value SlowScanJsonString();
+  Handle<Object> SlowScanJsonString();
 
   // A JSON number (production JSONNumber) is a subset of the valid JavaScript
   // decimal number literals.
   // It includes an optional minus sign, must have at least one
   // digit before and after a decimal point, may not have prefixed zeros (unless
   // the integer part is zero), and may include an exponent part (e.g., "e-10").
   // Hexadecimal and octal numbers are not allowed.
-  Token::Value ScanJsonNumber();
-
-  // Used to recognizes one of the literals "true", "false", or "null". These
-  // are the only valid JSON identifiers (productions JSONBooleanLiteral,
-  // JSONNullLiteral).
-  Token::Value ScanJsonIdentifier(const char* text, Token::Value token);
+  Handle<Object> ParseJsonNumber();
 
   // Parse a single JSON value from input (grammar production JSONValue).
   // A JSON value is either a (double-quoted) string literal, a number literal,
   // one of "true", "false", or "null", or an object or array literal.
   Handle<Object> ParseJsonValue();
 
   // Parse a JSON object literal (grammar production JSONObject).
   // An object literal is a squiggly-braced and comma separated sequence
   // (possibly empty) of key/value pairs, where the key is a JSON string
   // literal, the value is a JSON value, and the two are separated by a colon.
   // A JSON array dosn't allow numbers and identifiers as keys, like a
   // JavaScript array.
   Handle<Object> ParseJsonObject();
 
   // Parses a JSON array literal (grammar production JSONArray). An array
   // literal is a square-bracketed and comma separated sequence (possibly empty)
   // of JSON values.
   // A JSON array doesn't allow leaving out values from the sequence, nor does
   // it allow a terminal comma, like a JavaScript array does.
   Handle<Object> ParseJsonArray();
 
 
   // Mark that a parsing error has happened at the current token, and
   // return a null handle. Primarily for readability.
-  Handle<Object> ReportUnexpectedToken() { return Handle<Object>::null(); }
+  inline Handle<Object> ReportUnexpectedToken() {
+    return Handle<Object>::null();
+  }
 
-  // Peek at the next token.
-  Token::Value Peek() { return next_.token; }
-  // Scan the next token and return the token scanned on the last call.
-  Token::Value Next();
-
-  struct TokenInfo {
-    TokenInfo() : token(Token::ILLEGAL),
-                  beg_pos(0),
-                  end_pos(0) { }
-    Token::Value token;
-    int beg_pos;
-    int end_pos;
-  };
+  inline Isolate* isolate() { return isolate_; }
 
   static const int kInitialSpecialStringSize = 1024;
 
 
  private:
   Handle<String> source_;
   int source_length_;
   Handle<SeqAsciiString> seq_source_;
 
   bool is_sequential_ascii_;
-  // Current and next token
-  TokenInfo current_;
-  TokenInfo next_;
+  // begin and end position of scanned string or number
+  int beg_pos_;
+  int end_pos_;
+
   Isolate* isolate_;
   uc32 c0_;
   int position_;
 
-
-  Handle<String> string_val_;
   double number_;
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_JSON_PARSER_H_