[parser] reject parenthesized patterns as DestructuringAssignmentTargets

src/parsing/parser-base.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_PARSING_PARSER_BASE_H
 #define V8_PARSING_PARSER_BASE_H
 
 #include "src/ast/scopes.h"
 #include "src/bailout-reason.h"
 #include "src/hashmap.h"
@@ skipping 3259 matching lines @@
 
 
 template <typename Traits>
 void ParserBase<Traits>::CheckDestructuringElement(
     ExpressionT expression, ExpressionClassifier* classifier, int begin,
     int end) {
   static const MessageTemplate::Template message =
       MessageTemplate::kInvalidDestructuringTarget;
   const Scanner::Location location(begin, end);
   if (expression->IsArrayLiteral() || expression->IsObjectLiteral() ||
-      expression->IsAssignment())
+      expression->IsAssignment()) {
+    if (expression->is_parenthesized()) {
+      classifier->RecordPatternError(location, message);
+    }
     return;
+  }
+
   if (expression->IsProperty()) {
     classifier->RecordBindingPatternError(location, message);
   } else if (!this->IsAssignableIdentifier(expression)) {
     classifier->RecordPatternError(location, message);
+  } else if (expression->is_parenthesized()) {
+    classifier->RecordBindingPatternError(location, message);

[caitp (gmail), 2016/01/12 23:15:16]

technically, this bit isn't needed because of an UnexpectedToken error --- but
we could replace the unexpected token error with this, which might be a bit
nicer

[adamk, 2016/01/12 23:17:11]

I'd rather leave this out of the change if we were already reporting an error
here, leaving this change only as a correctness fix.

If you'd like to do a followup patch with a message test, that'd be fine.

[caitp (gmail), 2016/01/12 23:31:18]

Alright, done, anything else?

   }
 }
 
 
 #undef CHECK_OK
 #undef CHECK_OK_CUSTOM
 
 
 template <typename Traits>
 void ParserBase<Traits>::ObjectLiteralChecker::CheckProperty(
@@ skipping 45 matching lines @@
       return;
     }
     has_seen_constructor_ = true;
     return;
   }
 }
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_PARSING_PARSER_BASE_H