Allow leading + when parsing integers in fast case (it is allowed per library implementation, only …

runtime/lib/integers.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/bootstrap_natives.h"
 
 #include "vm/bigint_operations.h"
 #include "vm/dart_entry.h"
 #include "vm/exceptions.h"
 #include "vm/native_entry.h"
@@ skipping 171 matching lines @@
 
 
 DEFINE_NATIVE_ENTRY(Integer_parse, 1) {
   GET_NON_NULL_NATIVE_ARGUMENT(String, value, arguments->NativeArgAt(0));
   if (value.IsOneByteString()) {
     // Quick conversion for unpadded integers in strings.
     const intptr_t len = value.Length();
     if (len > 0) {
       const char* cstr = value.ToCString();
       ASSERT(cstr != NULL);
-      // Dart differences from strtol:
-      // a) '+5' is not a valid integer (leading plus).
-      if (cstr[0] != '+') {
-        char* p_end = NULL;
-        const int64_t int_value = strtoll(cstr, &p_end, 10);
-        if (p_end == (cstr + len)) {
-          if ((int_value != LLONG_MIN) && (int_value != LLONG_MAX)) {
-            return Integer::New(int_value);
-          }
+      char* p_end = NULL;
+      const int64_t int_value = strtoll(cstr, &p_end, 10);
+      if (p_end == (cstr + len)) {
+        if ((int_value != LLONG_MIN) && (int_value != LLONG_MAX)) {
+          return Integer::New(int_value);
         }
       }
     }
   }
 
   Scanner scanner(value, Symbols::Empty());
   const Scanner::GrowableTokenStream& tokens = scanner.GetStream();
   String* int_string;
   bool is_positive;
   if (Scanner::IsValidLiteral(tokens,
@@ skipping 113 matching lines @@
 
 DEFINE_NATIVE_ENTRY(Bigint_bitNegate, 1) {
   const Bigint& value = Bigint::CheckedHandle(arguments->NativeArgAt(0));
   const Bigint& result = Bigint::Handle(BigintOperations::BitNot(value));
   ASSERT(CheckInteger(value));
   ASSERT(CheckInteger(result));
   return result.AsValidInteger();
 }
 
 }  // namespace dart