[es6] implement destructuring assignment

src/ast-expression-visitor.cc

 // Copyright 2015 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/v8.h"
 
 #include "src/ast-expression-visitor.h"
 
 #include "src/ast.h"
 #include "src/codegen.h"
@@ skipping 212 matching lines @@
 void AstExpressionVisitor::VisitLiteral(Literal* expr) {
   VisitExpression(expr);
 }
 
 
 void AstExpressionVisitor::VisitRegExpLiteral(RegExpLiteral* expr) {
   VisitExpression(expr);
 }
 
 
+void AstExpressionVisitor::VisitAssignmentPattern(AssignmentPattern* expr) {
+  VisitExpression(expr);
+  RECURSE_EXPRESSION(Visit(expr->expression()));

[adamk, 2015/11/20 22:42:58]

For each visitor, how did you decide whether to visit the expression vs the
pattern? This is another reason why it would make more sense to handle this in
VisitAssignment, it's sort of meaningless to visit an assignment pattern without
more context.

+}
+
+
 void AstExpressionVisitor::VisitObjectLiteral(ObjectLiteral* expr) {
   VisitExpression(expr);
   ZoneList<ObjectLiteralProperty*>* props = expr->properties();
   for (int i = 0; i < props->length(); ++i) {
     ObjectLiteralProperty* prop = props->at(i);
     if (!prop->key()->IsLiteral()) {
       RECURSE_EXPRESSION(Visit(prop->key()));
     }
     RECURSE_EXPRESSION(Visit(prop->value()));
   }
@@ skipping 145 matching lines @@
 void AstExpressionVisitor::VisitSuperCallReference(SuperCallReference* expr) {
   VisitExpression(expr);
   RECURSE_EXPRESSION(VisitVariableProxy(expr->this_var()));
   RECURSE_EXPRESSION(VisitVariableProxy(expr->new_target_var()));
   RECURSE_EXPRESSION(VisitVariableProxy(expr->this_function_var()));
 }
 
 
 }  // namespace internal
 }  // namespace v8