[bootstrapper] add checks for variable bindings in native scripts.

src/ast/scopes.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/scopes.h"
 
 #include "src/accessors.h"
 #include "src/ast/scopeinfo.h"
 #include "src/bootstrapper.h"
 #include "src/messages.h"
@@ skipping 290 matching lines @@
     AstNodeFactory ast_node_factory(info->ast_value_factory());
     if (!top->AllocateVariables(info, &ast_node_factory)) {
       DCHECK(top->pending_error_handler_.has_pending_error());
       top->pending_error_handler_.ThrowPendingError(info->isolate(),
                                                     info->script());
       return false;
     }
   }
 
 #ifdef DEBUG
-  bool native = info->isolate()->bootstrapper()->IsActive();
-  if (!info->shared_info().is_null()) {
-    Object* script = info->shared_info()->script();
-    native = script->IsScript() &&
-             Script::cast(script)->type() == Script::TYPE_NATIVE;
+  if (info->script_is_native() ? FLAG_print_builtin_scopes
+                               : FLAG_print_scopes) {
+    scope->Print();
   }
-
-  if (native ? FLAG_print_builtin_scopes : FLAG_print_scopes) scope->Print();
 #endif
 
   info->set_scope(scope);
   return true;
 }
 
 
 void Scope::Initialize() {
   DCHECK(!already_resolved());
 
@@ skipping 825 matching lines @@
                             AstNodeFactory* factory) {
   DCHECK(info->script_scope()->is_script_scope());
 
   // If the proxy is already resolved there's nothing to do
   // (functions and consts may be resolved by the parser).
   if (proxy->is_resolved()) return true;
 
   // Otherwise, try to resolve the variable.
   BindingKind binding_kind;
   Variable* var = LookupRecursive(proxy, &binding_kind, factory);
+
+#ifdef DEBUG
+  if (info->script_is_native()) {
+    // To avoid polluting the global object in native scripts
+    //  - Variables must not be allocated to the global scope.
+    CHECK_NOT_NULL(outer_scope());
+    //  - Variables must be bound locally or unallocated.
+    CHECK_EQ(BOUND, binding_kind);
+    VariableLocation location = var->location();
+    CHECK(location == VariableLocation::LOCAL ||
+          location == VariableLocation::CONTEXT ||
+          location == VariableLocation::PARAMETER ||
+          location == VariableLocation::UNALLOCATED);
+  }
+#endif
+
   switch (binding_kind) {
     case BOUND:
       // We found a variable binding.
       if (is_strong(language_mode())) {
         if (!CheckStrongModeDeclaration(proxy, var)) return false;
       }
       break;
 
     case BOUND_EVAL_SHADOWED:
       // We either found a variable binding that might be shadowed by eval  or
@@ skipping 491 matching lines @@
       function_ != NULL && function_->proxy()->var()->IsContextSlot();
   return num_heap_slots() - Context::MIN_CONTEXT_SLOTS - num_global_slots() -
          (is_function_var_in_context ? 1 : 0);
 }
 
 
 int Scope::ContextGlobalCount() const { return num_global_slots(); }
 
 }  // namespace internal
 }  // namespace v8