[es6] implement destructuring assignment [clean diff]

src/parser.h

 // 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.
 
 #ifndef V8_PARSER_H_
 #define V8_PARSER_H_
 
 #include "src/allocation.h"
 #include "src/ast.h"
 #include "src/compiler.h"  // TODO(titzer): remove this include dependency
@@ skipping 542 matching lines @@
 
   explicit ParserFormalParameters(Scope* scope)
       : FormalParametersBase(scope), params(4, scope->zone()) {}
   ZoneList<Parameter> params;
 
   int Arity() const { return params.length(); }
   const Parameter& at(int i) const { return params[i]; }
 };
 
 
+struct MarkedAssignment {
+  Scope* scope;
+  Assignment* assignment;
+};
+
+
 class ParserTraits {
  public:
   struct Type {
     // TODO(marja): To be removed. The Traits object should contain all the data
     // it needs.
     typedef v8::internal::Parser* Parser;
 
     typedef Variable GeneratorVariable;
 
     typedef v8::internal::AstProperties AstProperties;
@@ skipping 11 matching lines @@
     typedef ParserFormalParameters::Parameter FormalParameter;
     typedef ParserFormalParameters FormalParameters;
     typedef ZoneList<v8::internal::Statement*>* StatementList;
 
     // For constructing objects returned by the traversing functions.
     typedef AstNodeFactory Factory;
   };
 
   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;
   bool IsEvalOrArguments(const AstRawString* identifier) const;
   bool IsUndefined(const AstRawString* identifier) const;
   V8_INLINE bool IsFutureStrictReserved(const AstRawString* identifier) const;
 
   // Returns true if the expression is of type "this.foo".
   static bool IsThisProperty(Expression* expression);
 
@@ skipping 265 matching lines @@
   V8_INLINE ZoneList<v8::internal::Expression*>* PrepareSpreadArguments(
       ZoneList<v8::internal::Expression*>* list);
   V8_INLINE void MaterializeUnspreadArgumentsLiterals(int count) {}
   V8_INLINE Expression* SpreadCall(Expression* function,
                                    ZoneList<v8::internal::Expression*>* args,
                                    int pos);
   V8_INLINE Expression* SpreadCallNew(Expression* function,
                                       ZoneList<v8::internal::Expression*>* args,
                                       int pos);
 
+  V8_INLINE Expression* RewriteDestructuringAssignmentExpression(
+      Expression* expression);
+
  private:
   Parser* parser_;
 };
 
 
 class Parser : public ParserBase<ParserTraits> {
  public:
   explicit Parser(ParseInfo* info);
   ~Parser() {
     delete reusable_preparser_;
@@ skipping 304 matching lines @@
                                    Expression* tag);
   uint32_t ComputeTemplateLiteralHash(const TemplateLiteral* lit);
 
   ZoneList<v8::internal::Expression*>* PrepareSpreadArguments(
       ZoneList<v8::internal::Expression*>* list);
   Expression* SpreadCall(Expression* function,
                          ZoneList<v8::internal::Expression*>* args, int pos);
   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
   Target* target_stack_;  // for break, continue statements
   ScriptCompiler::CompileOptions compile_options_;
   ParseData* cached_parse_data_;
 
   PendingCompilationErrorHandler pending_error_handler_;
 
   // Other information which will be stored in Parser and moved to Isolate after
   // parsing.
   int use_counts_[v8::Isolate::kUseCounterFeatureCount];
   int total_preparse_skipped_;
   HistogramTimer* pre_parse_timer_;
 
   bool parsing_on_main_thread_;
+
+  // Track ambiguous expressions, to be rewritten later.
+  Collector<MarkedAssignment> marked_assignments_collector_;
 };
 
 
 bool ParserTraits::IsFutureStrictReserved(
     const AstRawString* identifier) const {
   return parser_->scanner()->IdentifierIsFutureStrictReserved(identifier);
 }
 
 
 Scope* ParserTraits::NewScope(Scope* parent_scope, ScopeType scope_type,
@@ skipping 152 matching lines @@
     }
   }
 }
 
 
 DoExpression* ParserTraits::ParseDoExpression(bool* ok) {
   return parser_->ParseDoExpression(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
 
 #endif  // V8_PARSER_H_