[destructuring] Implement BindingArrayPattern

src/parser.cc

Index: src/parser.cc
diff --git a/src/parser.cc b/src/parser.cc
index 374b59c7a7e9b4e78707bd57d0ce94ad266e6bdf..9e1d8fdcf3069a4dfbe0645360973f3e34e1f63e 100644
--- a/src/parser.cc
+++ b/src/parser.cc
@@ -3060,6 +3060,48 @@ WhileStatement* Parser::ParseWhileStatement(
 }
 
 
+// !%_IsSpecObject(result = iterator.next()) &&
+//     %ThrowIteratorResultNotAnObject(result)
+Expression* Parser::BuildIteratorNextResult(Expression* iterator,
+                                            Variable* result, int pos) {
+  Expression* next_literal = factory()->NewStringLiteral(
+      ast_value_factory()->next_string(), RelocInfo::kNoPosition);
+  Expression* next_property =
+      factory()->NewProperty(iterator, next_literal, RelocInfo::kNoPosition);
+  ZoneList<Expression*>* next_arguments =
+      new (zone()) ZoneList<Expression*>(0, zone());
+  Expression* next_call =
+      factory()->NewCall(next_property, next_arguments, pos);
+  Expression* result_proxy = factory()->NewVariableProxy(result);
+  Expression* left =
+      factory()->NewAssignment(Token::ASSIGN, result_proxy, next_call, pos);
+
+  // %_IsSpecObject(...)
+  ZoneList<Expression*>* is_spec_object_args =
+      new (zone()) ZoneList<Expression*>(1, zone());
+  is_spec_object_args->Add(left, zone());
+  Expression* is_spec_object_call = factory()->NewCallRuntime(
+      ast_value_factory()->is_spec_object_string(),
+      Runtime::FunctionForId(Runtime::kInlineIsSpecObject), is_spec_object_args,
+      pos);
+
+  // %ThrowIteratorResultNotAnObject(result)
+  Expression* result_proxy_again = factory()->NewVariableProxy(result);
+  ZoneList<Expression*>* throw_arguments =
+      new (zone()) ZoneList<Expression*>(1, zone());
+  throw_arguments->Add(result_proxy_again, zone());
+  Expression* throw_call = factory()->NewCallRuntime(
+      ast_value_factory()->throw_iterator_result_not_an_object_string(),
+      Runtime::FunctionForId(Runtime::kThrowIteratorResultNotAnObject),

[arv (Not doing code reviews), 2015/05/19 17:03:48]

Can you use a NewTypeError Expression instead of adding this runtime function?

Since we already have it I think it is OK but we should probably remove some of
these later...

[Dmitry Lomov (no reviews), 2015/05/20 07:42:42]

I tried that, need to change NewThrowTypeError to accept arbitrary expressions
instead of just literals for arg so too much unrelated change in this CL. Will
do in the follow-up.

+      throw_arguments, pos);
+
+  return factory()->NewBinaryOperation(
+      Token::AND,
+      factory()->NewUnaryOperation(Token::NOT, is_spec_object_call, pos),
+      throw_call, pos);
+}
+
+
 void Parser::InitializeForEachStatement(ForEachStatement* stmt,
                                         Expression* each,
                                         Expression* subject,
@@ -3087,41 +3129,8 @@ void Parser::InitializeForEachStatement(ForEachStatement* stmt,
     {
       // result = iterator.next()
       Expression* iterator_proxy = factory()->NewVariableProxy(iterator);
-      Expression* next_literal = factory()->NewStringLiteral(
-          ast_value_factory()->next_string(), RelocInfo::kNoPosition);
-      Expression* next_property = factory()->NewProperty(
-          iterator_proxy, next_literal, RelocInfo::kNoPosition);
-      ZoneList<Expression*>* next_arguments =
-          new (zone()) ZoneList<Expression*>(0, zone());
-      Expression* next_call = factory()->NewCall(next_property, next_arguments,
-                                                 subject->position());
-      Expression* result_proxy = factory()->NewVariableProxy(result);
-      next_result = factory()->NewAssignment(Token::ASSIGN, result_proxy,
-                                             next_call, subject->position());
-
-      // %_IsSpecObject(...)
-      ZoneList<Expression*>* is_spec_object_args =
-          new (zone()) ZoneList<Expression*>(1, zone());
-      is_spec_object_args->Add(next_result, zone());
-      Expression* is_spec_object_call = factory()->NewCallRuntime(
-          ast_value_factory()->is_spec_object_string(),
-          Runtime::FunctionForId(Runtime::kInlineIsSpecObject),
-          is_spec_object_args, subject->position());
-
-      // %ThrowIteratorResultNotAnObject(result)
-      Expression* result_proxy_again = factory()->NewVariableProxy(result);
-      ZoneList<Expression*>* throw_arguments =
-          new (zone()) ZoneList<Expression*>(1, zone());
-      throw_arguments->Add(result_proxy_again, zone());
-      Expression* throw_call = factory()->NewCallRuntime(
-          ast_value_factory()->throw_iterator_result_not_an_object_string(),
-          Runtime::FunctionForId(Runtime::kThrowIteratorResultNotAnObject),
-          throw_arguments, subject->position());
-
-      next_result = factory()->NewBinaryOperation(
-          Token::AND, factory()->NewUnaryOperation(
-                          Token::NOT, is_spec_object_call, subject->position()),
-          throw_call, subject->position());
+      next_result =
+          BuildIteratorNextResult(iterator_proxy, result, subject->position());
     }
 
     // result.done