Stop emitting kSloppyLexical errors when --harmony-sloppy-let is enabled

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 2695 matching lines @@
       !scanner()->HasAnyLineTerminatorBeforeNext() && expr != NULL &&
       expr->AsVariableProxy() != NULL &&
       expr->AsVariableProxy()->raw_name() ==
           ast_value_factory()->native_string() &&
       !scanner()->literal_contains_escapes()) {
     return ParseNativeDeclaration(ok);
   }
 
   // Parsed expression statement, followed by semicolon.
   // Detect attempts at 'let' declarations in sloppy mode.
-  if (peek() == Token::IDENTIFIER && expr->AsVariableProxy() != NULL &&
+  if (!allow_harmony_sloppy_let() && peek() == Token::IDENTIFIER &&
+      expr->AsVariableProxy() != NULL &&
       expr->AsVariableProxy()->raw_name() ==
           ast_value_factory()->let_string()) {
     ReportMessage(MessageTemplate::kSloppyLexical, NULL);
     *ok = false;
     return NULL;
   }
   ExpectSemicolon(CHECK_OK);
   return factory()->NewExpressionStatement(expr, pos);
 }
 
@@ skipping 1058 matching lines @@
       }
     }
   }
 
   // Standard 'for' loop
   ForStatement* loop = factory()->NewForStatement(labels, stmt_pos);
   Target target(&this->target_stack_, loop);
 
   // Parsed initializer at this point.
   // Detect attempts at 'let' declarations in sloppy mode.
-  if (peek() == Token::IDENTIFIER && is_sloppy(language_mode()) &&
-      is_let_identifier_expression) {
+  if (!allow_harmony_sloppy_let() && peek() == Token::IDENTIFIER &&
+      is_sloppy(language_mode()) && is_let_identifier_expression) {
     ReportMessage(MessageTemplate::kSloppyLexical, NULL);
     *ok = false;
     return NULL;
   }
   Expect(Token::SEMICOLON, CHECK_OK);
 
   // If there are let bindings, then condition and the next statement of the
   // for loop must be parsed in a new scope.
   Scope* inner_scope = NULL;
   if (lexical_bindings.length() > 0) {
@@ skipping 2436 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