[strong] Implement static restrictions on binding 'undefined' in arrow functions

src/preparser.cc

 // Copyright 2011 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.
 
 #include <cmath>
 
 #include "src/allocation.h"
 #include "src/base/logging.h"
 #include "src/conversions-inl.h"
 #include "src/conversions.h"
@@ skipping 898 matching lines @@
   FunctionState function_state(&function_state_, &scope_, function_scope, kind,
                                &factory);
   //  FormalParameterList ::
   //    '(' (Identifier)*[','] ')'
   Expect(Token::LPAREN, CHECK_OK);
   int start_position = position();
   DuplicateFinder duplicate_finder(scanner()->unicode_cache());
   // We don't yet know if the function will be strict, so we cannot yet produce
   // errors for parameter names or duplicates. However, we remember the
   // locations of these errors if they occur and produce the errors later.
-  Scanner::Location eval_args_error_loc = Scanner::Location::invalid();
-  Scanner::Location dupe_error_loc = Scanner::Location::invalid();
-  Scanner::Location reserved_error_loc = Scanner::Location::invalid();
+  Scanner::Location eval_args_loc = Scanner::Location::invalid();
+  Scanner::Location dupe_loc = Scanner::Location::invalid();
+  Scanner::Location reserved_loc = Scanner::Location::invalid();
 
   // Similarly for strong mode.
-  Scanner::Location undefined_error_loc = Scanner::Location::invalid();
+  Scanner::Location undefined_loc = Scanner::Location::invalid();
 
   bool is_rest = false;
   bool done = arity_restriction == FunctionLiteral::GETTER_ARITY ||
       (peek() == Token::RPAREN &&
        arity_restriction != FunctionLiteral::SETTER_ARITY);
   while (!done) {
     bool is_strict_reserved = false;
     is_rest = peek() == Token::ELLIPSIS && allow_harmony_rest_params();
     if (is_rest) {
       Consume(Token::ELLIPSIS);
     }
 
     Identifier param_name =
         ParseIdentifierOrStrictReservedWord(&is_strict_reserved, CHECK_OK);
-    if (!eval_args_error_loc.IsValid() && param_name.IsEvalOrArguments()) {
-      eval_args_error_loc = scanner()->location();
+    if (!eval_args_loc.IsValid() && param_name.IsEvalOrArguments()) {
+      eval_args_loc = scanner()->location();
     }
-    if (!undefined_error_loc.IsValid() && param_name.IsUndefined()) {
-      undefined_error_loc = scanner()->location();
+    if (!undefined_loc.IsValid() && param_name.IsUndefined()) {
+      undefined_loc = scanner()->location();
     }
-    if (!reserved_error_loc.IsValid() && is_strict_reserved) {
-      reserved_error_loc = scanner()->location();
+    if (!reserved_loc.IsValid() && is_strict_reserved) {
+      reserved_loc = scanner()->location();
     }
 
     int prev_value = scanner()->FindSymbol(&duplicate_finder, 1);
 
-    if (!dupe_error_loc.IsValid() && prev_value != 0) {
-      dupe_error_loc = scanner()->location();
+    if (!dupe_loc.IsValid() && prev_value != 0) {
+      dupe_loc = scanner()->location();
     }
 
     if (arity_restriction == FunctionLiteral::SETTER_ARITY) break;
     done = (peek() == Token::RPAREN);
     if (!done) {
       if (is_rest) {
         ReportMessageAt(scanner()->peek_location(), "param_after_rest");
         *ok = false;
         return Expression::Default();
       }
@@ skipping 14 matching lines @@
   } else {
     ParseStatementList(Token::RBRACE, CHECK_OK);
   }
   Expect(Token::RBRACE, CHECK_OK);
 
   // Validate name and parameter names. We can do this only after parsing the
   // function, since the function can declare itself strict.
   CheckFunctionName(language_mode(), kind, function_name,
                     name_is_strict_reserved, function_name_location, CHECK_OK);
   const bool use_strict_params = is_rest || IsConciseMethod(kind);
-  CheckFunctionParameterNames(language_mode(), use_strict_params,
-                              eval_args_error_loc, undefined_error_loc,
-                              dupe_error_loc, reserved_error_loc, CHECK_OK);
+  CheckFunctionParameterNames(language_mode(), use_strict_params, eval_args_loc,
+                              undefined_loc, dupe_loc, reserved_loc, CHECK_OK);
 
   if (is_strict(language_mode())) {
     int end_position = scanner()->location().end_pos;
     CheckStrictOctalLiteral(start_position, end_position, CHECK_OK);
   }
 
   if (is_strong(language_mode()) && IsSubclassConstructor(kind)) {
     if (!function_state.super_call_location().IsValid()) {
       ReportMessageAt(function_name_location, "strong_super_call_missing",
                       kReferenceError);
@@ skipping 89 matching lines @@
 
   DCHECK(!spread_pos.IsValid());
 
   return Expression::Default();
 }
 
 #undef CHECK_OK
 
 
 } }  // v8::internal