[es6] implement destructuring assignment [clean diff]

src/parser.h

Index: src/parser.h
diff --git a/src/parser.h b/src/parser.h
index 35a6f3af20bdc7022e7ff5ac065b132533afe4c6..26a56668d8aab6373f11ca77d637606b880c0a12 100644
--- a/src/parser.h
+++ b/src/parser.h
@@ -560,6 +560,12 @@ struct ParserFormalParameters : FormalParametersBase {
 };
 
 
+struct MarkedAssignment {
+  Scope* scope;
+  Assignment* assignment;
+};
+
+
 class ParserTraits {
  public:
   struct Type {
@@ -591,6 +597,8 @@ class ParserTraits {
 
   explicit ParserTraits(Parser* parser) : parser_(parser) {}
 
+  V8_INLINE void MarkDestructuringAssignment(Assignment* assignment);
+
   // Helper functions for recursive descent.
   bool IsEval(const AstRawString* identifier) const;
   bool IsArguments(const AstRawString* identifier) const;
@@ -876,6 +884,9 @@ class ParserTraits {
                                       ZoneList<v8::internal::Expression*>* args,
                                       int pos);
 
+  V8_INLINE Expression* RewriteDestructuringAssignmentExpression(
+      Expression* expression);
+
  private:
   Parser* parser_;
 };
@@ -1200,6 +1211,8 @@ class Parser : public ParserBase<ParserTraits> {
   Expression* SpreadCallNew(Expression* function,
                             ZoneList<v8::internal::Expression*>* args, int pos);
 
+  Expression* RewriteDestructuringAssignmentExpression(Expression* expression);
+
   Scanner scanner_;
   PreParser* reusable_preparser_;
   Scope* original_scope_;  // for ES5 function declarations in sloppy eval
@@ -1216,6 +1229,9 @@ class Parser : public ParserBase<ParserTraits> {
   HistogramTimer* pre_parse_timer_;
 
   bool parsing_on_main_thread_;
+
+  // Track ambiguous expressions, to be rewritten later.
+  Collector<MarkedAssignment> marked_assignments_collector_;
 };
 
 
@@ -1388,6 +1404,21 @@ DoExpression* ParserTraits::ParseDoExpression(bool* ok) {
 }
 
 
+void ParserTraits::MarkDestructuringAssignment(Assignment* assignment) {
+  DCHECK(assignment->IsAssignment());
+  MarkedAssignment mark;
+  mark.assignment = assignment;
+  mark.scope = parser_->scope_;
+  parser_->marked_assignments_collector_.Add(mark);
+}
+
+
+Expression* ParserTraits::RewriteDestructuringAssignmentExpression(
+    Expression* expression) {
+  return parser_->RewriteDestructuringAssignmentExpression(expression);
+}
+
+
 }  // namespace internal
 }  // namespace v8