Sloppy-mode let parsing

src/parser.cc

 // 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.
 
 #include "src/parser.h"
 
 #include "src/api.h"
 #include "src/ast.h"
 #include "src/ast-literal-reindexer.h"
 #include "src/bailout-reason.h"
@@ skipping 1384 matching lines @@
       }
       return ParseClassDeclaration(NULL, ok);
     case Token::CONST:
       if (allow_const()) {
         return ParseVariableStatement(kStatementListItem, NULL, ok);
       }
       break;
     case Token::VAR:
       return ParseVariableStatement(kStatementListItem, NULL, ok);
     case Token::LET:
-      if (allow_let()) {
+      if (IsNextLetKeyword()) {
         return ParseVariableStatement(kStatementListItem, NULL, ok);
       }
       break;
     default:
       break;
   }
   return ParseStatement(NULL, ok);
 }
 
 
@@ skipping 1229 matching lines @@
                                   ? MessageTemplate::kStrongConstructorThis
                                   : MessageTemplate::kStrongConstructorSuper);
               *ok = false;
               return nullptr;
             }
         }
         return factory()->NewExpressionStatement(expr, pos);
       }
       break;
 
-    // TODO(arv): Handle `let [`
-    // https://code.google.com/p/v8/issues/detail?id=3847
-
     default:
       break;
   }
 
   bool starts_with_idenfifier = peek_any_identifier();
   Expression* expr = ParseExpression(true, CHECK_OK);
   if (peek() == Token::COLON && starts_with_idenfifier && expr != NULL &&
       expr->AsVariableProxy() != NULL &&
       !expr->AsVariableProxy()->is_this()) {
     // Expression is a single identifier, and not, e.g., a parenthesized
@@ skipping 889 matching lines @@
   Scope* saved_scope = scope_;
   Scope* for_scope = NewScope(scope_, BLOCK_SCOPE);
   scope_ = for_scope;
   Expect(Token::FOR, CHECK_OK);
   Expect(Token::LPAREN, CHECK_OK);
   for_scope->set_start_position(scanner()->location().beg_pos);
   bool is_let_identifier_expression = false;
   DeclarationParsingResult parsing_result;
   if (peek() != Token::SEMICOLON) {
     if (peek() == Token::VAR || (peek() == Token::CONST && allow_const()) ||
-        (peek() == Token::LET && allow_let())) {
+        (peek() == Token::LET && IsNextLetKeyword())) {
       ParseVariableDeclarations(kForStatement, &parsing_result, CHECK_OK);
       is_const = parsing_result.descriptor.mode == CONST;
 
       int num_decl = parsing_result.declarations.length();
       bool accept_IN = num_decl >= 1;
       bool accept_OF = true;
       ForEachStatement::VisitMode mode;
       int each_beg_pos = scanner()->location().beg_pos;
       int each_end_pos = scanner()->location().end_pos;
 
@@ skipping 2528 matching lines @@
 
 Expression* Parser::SpreadCallNew(Expression* function,
                                   ZoneList<v8::internal::Expression*>* args,
                                   int pos) {
   args->InsertAt(0, function, zone());
 
   return factory()->NewCallRuntime(Context::REFLECT_CONSTRUCT_INDEX, args, pos);
 }
 }  // namespace internal
 }  // namespace v8