[printing] show symbols when using %DebugPrint

src/objects-printer.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.
 
 #include "src/objects.h"
 
 #include "src/disasm.h"
 #include "src/disassembler.h"
 #include "src/interpreter/bytecodes.h"
 #include "src/objects-inl.h"
@@ skipping 362 matching lines @@
     PRINT_ELEMENTS(INT16_ELEMENTS, FixedInt16Array)
     PRINT_ELEMENTS(UINT32_ELEMENTS, FixedUint32Array)
     PRINT_ELEMENTS(INT32_ELEMENTS, FixedInt32Array)
     PRINT_ELEMENTS(FLOAT32_ELEMENTS, FixedFloat32Array)
     PRINT_ELEMENTS(FLOAT64_ELEMENTS, FixedFloat64Array)
 
 #undef PRINT_ELEMENTS
 
     case DICTIONARY_ELEMENTS:
     case SLOW_STRING_WRAPPER_ELEMENTS:
-      os << "\n - elements: ";
       elements()->Print(os);
       break;
     case FAST_SLOPPY_ARGUMENTS_ELEMENTS:
     case SLOW_SLOPPY_ARGUMENTS_ELEMENTS: {
       FixedArray* p = FixedArray::cast(elements());
       os << "\n   parameter map:";
       for (int i = 2; i < p->length(); i++) {
         os << " " << (i - 2) << ":" << Brief(p->get(i));
       }
       os << "\n   context: " << Brief(p->get(0))
@@ skipping 23 matching lines @@
      << ElementsKindToString(obj->map()->elements_kind());
   if (obj->elements()->map() == obj->GetHeap()->fixed_cow_array_map()) {
     os << " (COW)";
   }
   os << "]";
 }
 
 
 static void JSObjectPrintBody(std::ostream& os, JSObject* obj,  // NOLINT
                               bool print_elements = true) {
-  os << "\n {";
+  os << "\n - properties = {";
   obj->PrintProperties(os);
-  if (print_elements) obj->PrintElements(os);
   os << "\n }\n";
+  if (print_elements && obj->elements()->length() > 0) {
+    os << " - elements = {";
+    obj->PrintElements(os);
+    os << "\n }\n";
+  }
 }
 
 
 void JSObject::JSObjectPrint(std::ostream& os) {  // NOLINT
   JSObjectPrintHeader(os, this, nullptr);
   JSObjectPrintBody(os, this);
 }
 
 void JSArray::JSArrayPrint(std::ostream& os) {  // NOLINT
   JSObjectPrintHeader(os, this, "JSArray");
@@ skipping 268 matching lines @@
     os << truncated_epilogue;
   }
 
   if (!StringShape(this).IsInternalized()) os << "\"";
 }
 
 
 void Name::NamePrint(std::ostream& os) {  // NOLINT
   if (IsString()) {
     String::cast(this)->StringPrint(os);
-  } else if (IsSymbol()) {
-    Symbol::cast(this)->name()->Print(os);
   } else {
     os << Brief(this);
   }
 }
 
 
 static const char* const weekdays[] = {
   "???", "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
 };
 
@@ skipping 606 matching lines @@
 void JSObject::PrintTransitions(std::ostream& os) {  // NOLINT
   Object* transitions = map()->raw_transitions();
   int num_transitions = TransitionArray::NumberOfTransitions(transitions);
   if (num_transitions == 0) return;
   os << "\n - transitions";
   TransitionArray::PrintTransitions(os, transitions, false);
 }
 #endif  // defined(DEBUG) || defined(OBJECT_PRINT)
 }  // namespace internal
 }  // namespace v8