[parser] Allow duplicate __proto__ keys in patterns

src/parsing/expression-classifier.h

Index: src/parsing/expression-classifier.h
diff --git a/src/parsing/expression-classifier.h b/src/parsing/expression-classifier.h
index 2c555b9c9886fa28972024f0ebd187c665c28ee7..8b782d93a3e81c5c9acdb64130cf824d932ef8c7 100644
--- a/src/parsing/expression-classifier.h
+++ b/src/parsing/expression-classifier.h
@@ -25,7 +25,8 @@ namespace internal {
   T(CoverInitializedNameProduction, 8)          \
   T(TailCallExpressionProduction, 9)            \
   T(AsyncArrowFormalParametersProduction, 10)   \
-  T(AsyncBindingPatternProduction, 11)
+  T(AsyncBindingPatternProduction, 11)          \
+  T(AnnexBDuplicateProtoProduction, 12)

[adamk, 2016/08/19 20:17:07]

Let's just call this DuplicateProtoProduction.

[gsathya, 2016/08/19 23:22:57]

Changed to ObjectLiteralProduction as discussed offline

 
 
 template <typename Traits>
@@ -74,7 +75,8 @@ class ExpressionClassifier {
     AllProductions =
         (ExpressionProductions | PatternProductions |
          FormalParametersProductions | ArrowFormalParametersProduction |
-         CoverInitializedNameProduction | AsyncArrowFormalParametersProduction)
+         CoverInitializedNameProduction | AsyncArrowFormalParametersProduction |
+         AnnexBDuplicateProtoProduction)
   };
 
   enum FunctionProperties : unsigned {
@@ -201,6 +203,15 @@ class ExpressionClassifier {
   V8_INLINE const Error& tail_call_expression_error() const {
     return reported_error(kTailCallExpressionProduction);
   }
+
+  V8_INLINE bool has_annexb_duplicate_proto() const {
+    return !is_valid(AnnexBDuplicateProtoProduction);
+  }
+
+  V8_INLINE const Error& annexb_duplicate_proto_error() const {
+    return reported_error(kAnnexBDuplicateProtoProduction);
+  }
+
   V8_INLINE const Error& async_arrow_formal_parameters_error() const {
     return reported_error(kAsyncArrowFormalParametersProduction);
   }
@@ -330,6 +341,14 @@ class ExpressionClassifier {
     Add(Error(loc, message, kTailCallExpressionProduction, arg));
   }
 
+  void RecordAnnexBDuplicateProtoError(const Scanner::Location& loc,
+                                       MessageTemplate::Template message,
+                                       const char* arg = nullptr) {
+    if (has_annexb_duplicate_proto()) return;
+    invalid_productions_ |= AnnexBDuplicateProtoProduction;
+    Add(Error(loc, message, kAnnexBDuplicateProtoProduction, arg));
+  }
+
   void ForgiveCoverInitializedNameError() {
     if (!(invalid_productions_ & CoverInitializedNameProduction)) return;
     Error& e = reported_error(kCoverInitializedNameProduction);
@@ -344,6 +363,13 @@ class ExpressionClassifier {
     invalid_productions_ &= ~AssignmentPatternProduction;
   }
 
+  void ForgiveAnnexBDuplicateProtoError() {
+    if (!(invalid_productions_ & AnnexBDuplicateProtoProduction)) return;
+    Error& e = reported_error(kAnnexBDuplicateProtoProduction);
+    e.kind = kUnusedError;
+    invalid_productions_ &= ~AnnexBDuplicateProtoProduction;
+  }
+
   void Accumulate(ExpressionClassifier* inner, unsigned productions,
                   bool merge_non_patterns = true) {
     DCHECK_EQ(inner->reported_errors_, reported_errors_);