Implement handling of arrow functions in the parser

src/scanner.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Features shared by parsing and pre-parsing scanners.
 
 #include <cmath>
 
 #include "scanner.h"
 
@@ skipping 191 matching lines @@
   Token::RBRACE,       // 0x7d
   Token::BIT_NOT,      // 0x7e
   Token::ILLEGAL
 };
 
 
 Token::Value Scanner::Next() {
   current_ = next_;
   has_line_terminator_before_next_ = false;
   has_multiline_comment_before_next_ = false;
+  param_list_finder_.Update(current_.token, current_.location.beg_pos);
   if (static_cast<unsigned>(c0_) <= 0x7f) {
     Token::Value token = static_cast<Token::Value>(one_char_tokens[c0_]);
     if (token != Token::ILLEGAL) {
       int pos = source_pos();
       next_.token = token;
       next_.location.beg_pos = pos;
       next_.location.end_pos = pos + 1;
       Advance();
       return current_.token;
     }
@@ skipping 165 matching lines @@
             token = Select('=', Token::ASSIGN_SHR, Token::SHR);
           } else {
             token = Token::SAR;
           }
         } else {
           token = Token::GT;
         }
         break;
 
       case '=':
-        // = == ===
+        // = == === =>
         Advance();
         if (c0_ == '=') {
           token = Select('=', Token::EQ_STRICT, Token::EQ);
+        } else if (c0_ == '>') {
+          token = Select(Token::ARROW);
         } else {
           token = Token::ASSIGN;
         }
         break;
 
       case '!':
         // ! != !==
         Advance();
         if (c0_ == '=') {
           token = Select('=', Token::NE_STRICT, Token::NE);
@@ skipping 860 matching lines @@
     }
     backing_store_.Add(static_cast<uint8_t>((one_byte_length >> 7) | 0x80u));
   }
   backing_store_.Add(static_cast<uint8_t>(one_byte_length & 0x7f));
 
   backing_store_.AddBlock(bytes);
   return backing_store_.EndSequence().start();
 }
 
 } }  // namespace v8::internal