Remove support for + prefix in number literals

runtime/vm/scanner.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/scanner.h"
 
 #include "platform/assert.h"
 #include "vm/flags.h"
 #include "vm/object.h"
 #include "vm/object_store.h"
@@ skipping 171 matching lines @@
                              bool* is_positive,
                              String** value) {
   if ((tokens.length() == 2) &&
       (tokens[0].kind == literal_kind) &&
       (tokens[1].kind == Token::kEOS)) {
     *is_positive = true;
     *value = tokens[0].literal;
     return true;
   }
   if ((tokens.length() == 3) &&
-      ((tokens[0].kind == Token::kTIGHTADD) ||
+      ((tokens[0].kind == Token::kADD) ||
        (tokens[0].kind == Token::kSUB)) &&
       (tokens[1].kind == literal_kind) &&
       (tokens[2].kind == Token::kEOS)) {
     // Check there is no space between "+/-" and number.
     if ((tokens[0].offset + 1) != tokens[1].offset) {
       return false;
     }
-    *is_positive = tokens[0].kind == Token::kTIGHTADD;
+    *is_positive = tokens[0].kind == Token::kADD;
     *value = tokens[1].literal;
     return true;
   }
   return false;
 }
 
 
 void Scanner::ReadChar() {
   if (lookahead_pos_ < source_length_) {
     if (c0_ == '\n') {
@@ skipping 421 matching lines @@
         ScanLiteralStringChars(false);
       }
       break;
     }
     switch (c0_) {
       case '\0':
         current_token_.kind = Token::kEOS;
         break;
 
       case '+':  // +  ++  +=
-        ReadChar();
-        current_token_.kind =
-            IsNumberStart(c0_) ? Token::kTIGHTADD : Token::kADD;
-        // Unary + is not allowed for hexadecimal integers, so treat the
-        // + as a binary operator.
-        if ((c0_ == '0') &&
-            ((LookaheadChar(1) == 'x') || (LookaheadChar(1) == 'X'))) {
-          current_token_.kind = Token::kADD;
-        } else if (c0_ == '+') {
+        Recognize(Token::kADD);
+        if (c0_ == '+') {
           Recognize(Token::kINCR);
         } else if (c0_ == '=') {
           Recognize(Token::kASSIGN_ADD);
         }
         break;
 
       case '-':  // -  --  -=
         Recognize(Token::kSUB);
         if (c0_ == '-') {
           Recognize(Token::kDECR);
@@ skipping 300 matching lines @@
               "%c%#"Px"", kPrivateKeySeparator, key_value);
   const String& result = String::Handle(String::New(private_key, Heap::kOld));
   return result.raw();
 }
 
 
 void Scanner::InitOnce() {
 }
 
 }  // namespace dart