Rescope arrow-function parameter lists by moving the delta to the parameter scope

src/parsing/preparser.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_PREPARSER_H
 #define V8_PARSING_PREPARSER_H
 
 #include "src/ast/scopes.h"
 #include "src/bailout-reason.h"
 #include "src/base/hashmap.h"
@@ skipping 858 matching lines @@
                                       int* expected_property_count, bool* ok) {
     UNREACHABLE();
   }
 
   V8_INLINE PreParserStatementList ParseEagerFunctionBody(
       PreParserIdentifier function_name, int pos,
       const PreParserFormalParameters& parameters, FunctionKind kind,
       FunctionLiteral::FunctionType function_type, bool* ok);
 
   V8_INLINE void ParseArrowFunctionFormalParameterList(
-      PreParserFormalParameters* parameters,
-      PreParserExpression expression, const Scanner::Location& params_loc,
-      Scanner::Location* duplicate_loc, bool* ok);
+      PreParserFormalParameters* parameters, PreParserExpression expression,
+      const Scanner::Location& params_loc, Scanner::Location* duplicate_loc,
+      Scope::Snapshot& scope_snapshot, bool* ok);
 
   void ParseAsyncArrowSingleExpressionBody(
       PreParserStatementList body, bool accept_IN,
       Type::ExpressionClassifier* classifier, int pos, bool* ok);
 
   V8_INLINE PreParserExpression ParseAsyncFunctionExpression(bool* ok);
 
   void ReindexLiterals(const PreParserFormalParameters& paramaters) {}
 
   struct TemplateLiteralState {};
@@ skipping 292 matching lines @@
                                                 int pos) {
   return pre_parser_->factory()->NewCall(function, args, pos);
 }
 
 PreParserExpression PreParserTraits::SpreadCallNew(PreParserExpression function,
                                                    PreParserExpressionList args,
                                                    int pos) {
   return pre_parser_->factory()->NewCallNew(function, args, pos);
 }
 
-
 void PreParserTraits::ParseArrowFunctionFormalParameterList(
-    PreParserFormalParameters* parameters,
-    PreParserExpression params, const Scanner::Location& params_loc,
-    Scanner::Location* duplicate_loc, bool* ok) {
+    PreParserFormalParameters* parameters, PreParserExpression params,
+    const Scanner::Location& params_loc, Scanner::Location* duplicate_loc,
+    Scope::Snapshot& scope_snapshot, bool* ok) {
   // TODO(wingo): Detect duplicated identifiers in paramlists.  Detect parameter
   // lists that are too long.
 }
 
 PreParserExpression PreParserTraits::ParseAsyncFunctionExpression(bool* ok) {
   return pre_parser_->ParseAsyncFunctionExpression(ok);
 }
 
 PreParserExpression PreParserTraits::ParseDoExpression(bool* ok) {
   return pre_parser_->ParseDoExpression(ok);
@@ skipping 56 matching lines @@
     const PreParserFormalParameters& parameters, FunctionKind kind,
     FunctionLiteral::FunctionType function_type, bool* ok) {
   return pre_parser_->ParseEagerFunctionBody(function_name, pos, parameters,
                                              kind, function_type, ok);
 }
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_PARSING_PREPARSER_H