[es6] implement destructuring assignment

src/ast-expression-visitor.cc

Index: src/ast-expression-visitor.cc
diff --git a/src/ast-expression-visitor.cc b/src/ast-expression-visitor.cc
index b24abae24f1f220062ffda8d610a4ed36b4fe015..a2f37dea499cc505f66196eee1ca51d5e77d979a 100644
--- a/src/ast-expression-visitor.cc
+++ b/src/ast-expression-visitor.cc
@@ -32,6 +32,16 @@ namespace internal {
   } while (false)
 
 
+#define RECURSE_EXPRESSION_RETURN_IF_VISIT_NODE(call) \
+  do {                                                \
+    AstNode* node = call;                             \
+    if (node) {                                       \
+      RECURSE_EXPRESSION(Visit(node));                \
+      return;                                         \
+    }                                                 \
+  } while (false)
+
+
 AstExpressionVisitor::AstExpressionVisitor(Isolate* isolate, Expression* root)
     : root_(root), depth_(0) {
   InitializeAstVisitor(isolate);
@@ -255,7 +265,9 @@ void AstExpressionVisitor::VisitArrayLiteral(ArrayLiteral* expr) {
 
 
 void AstExpressionVisitor::VisitAssignment(Assignment* expr) {
+  RETURN_IF_VISIT_NODE(expr->destructuring_assignment());
   VisitExpression(expr);
+  RECURSE_EXPRESSION_RETURN_IF_VISIT_NODE(expr->destructuring_assignment());

[adamk, 2015/11/25 21:05:28]

Is this needed because VisitExpression could mutate |expr|?

[caitp (gmail), 2015/11/25 21:41:51]

I suppose it can, the InitializerRewriter  visitor does that, I think. AFAIK the
top-most RETURN_IF_VISIT_NODE probably should be removed, but I'm not positive

   RECURSE_EXPRESSION(Visit(expr->target()));
   RECURSE_EXPRESSION(Visit(expr->value()));
 }