Reland shipping of --harmony-destructuring-bind

src/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/scopes.h"
 
 #include "src/accessors.h"
 #include "src/bootstrapper.h"
 #include "src/messages.h"
 #include "src/parser.h"
@@ skipping 592 matching lines @@
 Expression* Scope::GetIllegalRedeclaration() {
   DCHECK(HasIllegalRedeclaration());
   return illegal_redecl_;
 }
 
 
 Declaration* Scope::CheckConflictingVarDeclarations() {
   int length = decls_.length();
   for (int i = 0; i < length; i++) {
     Declaration* decl = decls_[i];
-    if (decl->mode() != VAR && !is_block_scope()) continue;
+    // We don't create a separate scope to hold the function name of a function
+    // expression, so we have to make sure not to consider it when checking for
+    // conflicts (since it's conceptually "outside" the declaration scope).
+    if (is_function_scope() && decl == function()) continue;
+    if (IsLexicalVariableMode(decl->mode()) && !is_block_scope()) continue;
     const AstRawString* name = decl->proxy()->raw_name();
 
     // Iterate through all scopes until and including the declaration scope.
     Scope* previous = NULL;
     Scope* current = decl->scope();
     // Lexical vs lexical conflicts within the same scope have already been
     // captured in Parser::Declare. The only conflicts we still need to check
     // are lexical vs VAR, or any declarations within a declaration block scope
     // vs lexical declarations in its surrounding (function) scope.
-    if (decl->mode() != VAR) current = current->outer_scope_;
+    if (IsLexicalVariableMode(decl->mode())) current = current->outer_scope_;
     do {
       // There is a conflict if there exists a non-VAR binding.
       Variable* other_var = current->variables_.Lookup(name);
-      if (other_var != NULL && other_var->mode() != VAR) {
+      if (other_var != NULL && IsLexicalVariableMode(other_var->mode())) {
         return decl;
       }
       previous = current;
       current = current->outer_scope_;
     } while (!previous->is_declaration_scope());
   }
   return NULL;
 }
 
 
@@ skipping 1023 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