[es6] fix nested object literals with computed property names

src/ast.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/ast.h"
 
 #include <cmath>  // For isfinite.
 #include "src/builtins.h"
 #include "src/code-stubs.h"
 #include "src/contexts.h"
@@ skipping 415 matching lines @@
 
 void ObjectLiteral::BuildConstantProperties(Isolate* isolate) {
   if (!constant_properties_.is_null()) return;
 
   // Allocate a fixed array to hold all the constant properties.
   Handle<FixedArray> constant_properties = isolate->factory()->NewFixedArray(
       boilerplate_properties_ * 2, TENURED);
 
   int position = 0;
   // Accumulate the value in local variables and store it at the end.
-  bool is_simple = true;
+  // If computed properties are used, the literal is never simple.
+  bool is_simple = boilerplate_properties_ != 0 || properties()->length() == 0;

[wingo, 2015/08/24 16:04:40]

I am missing a bit of context.  Is boilerplate_properties always zero if there
are computed properties?  As an ignorant reader I would appreciate a
has_computed_properties() predicate :)

[caitp (gmail), 2015/08/24 16:08:27]

yeah, it can be organized that way for sure. I'm not totally sure why we don't
save the `has_computed_properties` flag in the literal, which is computed by the
parser already

   int depth_acc = 1;
   uint32_t max_element_index = 0;
   uint32_t elements = 0;
   for (int i = 0; i < properties()->length(); i++) {
     ObjectLiteral::Property* property = properties()->at(i);
     if (!IsBoilerplateProperty(property)) {
       is_simple = false;
       continue;
     }
 
@@ skipping 703 matching lines @@
 bool Literal::Match(void* literal1, void* literal2) {
   const AstValue* x = static_cast<Literal*>(literal1)->raw_value();
   const AstValue* y = static_cast<Literal*>(literal2)->raw_value();
   return (x->IsString() && y->IsString() && x->AsString() == y->AsString()) ||
          (x->IsNumber() && y->IsNumber() && x->AsNumber() == y->AsNumber());
 }
 
 
 }  // namespace internal
 }  // namespace v8