[d8] Add support for printing symbols

src/d8.cc

 // Copyright 2012 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.
 
 
 // Defined when linking against shared lib on Windows.
 #if defined(USING_V8_SHARED) && !defined(V8_SHARED)
 #define V8_SHARED
 #endif
 
@@ skipping 638 matching lines @@
 
 void Shell::Write(const v8::FunctionCallbackInfo<v8::Value>& args) {
   for (int i = 0; i < args.Length(); i++) {
     HandleScope handle_scope(args.GetIsolate());
     if (i != 0) {
       printf(" ");
     }
 
     // Explicitly catch potential exceptions in toString().
     v8::TryCatch try_catch(args.GetIsolate());
+    Local<Value> arg = args[i];
     Local<String> str_obj;
-    if (!args[i]
-             ->ToString(args.GetIsolate()->GetCurrentContext())
+
+    if (arg->IsSymbol()) {
+      arg = Local<Symbol>::Cast(arg)->Name();
+    }
+    if (!arg->ToString(args.GetIsolate()->GetCurrentContext())
              .ToLocal(&str_obj)) {
       try_catch.ReThrow();
       return;
     }
 
     v8::String::Utf8Value str(str_obj);
     int n = static_cast<int>(fwrite(*str, sizeof(**str), str.length(), stdout));
     if (n != str.length()) {
       printf("Error in fwrite\n");
       Exit(1);
@@ skipping 1879 matching lines @@
 }
 
 }  // namespace v8
 
 
 #ifndef GOOGLE3
 int main(int argc, char* argv[]) {
   return v8::Shell::Main(argc, argv);
 }
 #endif