[parser] partially revert "use-strict directives in function body affect init block"

src/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_PREPARSER_H
 #define V8_PREPARSER_H
 
 #include "src/v8.h"
 
 #include "src/bailout-reason.h"
@@ skipping 1621 matching lines @@
     return !tag.IsNoTemplateTag();
   }
 
   void AddFormalParameter(
       PreParserFormalParameters* parameters, PreParserExpression pattern,
       bool is_rest) {
     ++parameters->arity;
   }
   void DeclareFormalParameter(Scope* scope, PreParserIdentifier parameter,
                               bool is_simple,
-                              ExpressionClassifier* classifier) {}
+                              ExpressionClassifier* classifier) {
+    if (!is_simple) scope->SetHasNonSimpleParameters();
+  }
 
   void CheckConflictingVarDeclarations(Scope* scope, bool* ok) {}
 
   // Temporary glue; these functions will move to ParserBase.
   PreParserExpression ParseV8Intrinsic(bool* ok);
   PreParserExpression ParseFunctionLiteral(
       PreParserIdentifier name, Scanner::Location function_name_location,
       FunctionNameValidity function_name_validity, FunctionKind kind,
       int function_token_position, FunctionLiteral::FunctionType type,
       FunctionLiteral::ArityRestriction arity_restriction,
@@ skipping 77 matching lines @@
 
   // Parses a single function literal, from the opening parentheses before
   // parameters to the closing brace after the body.
   // Returns a FunctionEntry describing the body of the function in enough
   // detail that it can be lazily compiled.
   // The scanner is expected to have matched the "function" or "function*"
   // keyword and parameters, and have consumed the initial '{'.
   // At return, unless an error occurred, the scanner is positioned before the
   // the final '}'.
   PreParseResult PreParseLazyFunction(
-      LanguageMode language_mode, FunctionKind kind, ParserRecorder* log,
-      Scanner::BookmarkScope* bookmark = nullptr);
+      LanguageMode language_mode, FunctionKind kind, bool has_simple_parameters,
+      ParserRecorder* log, Scanner::BookmarkScope* bookmark = nullptr);
 
  private:
   friend class PreParserTraits;
 
   static const int kLazyParseTrialLimit = 200;
 
   // These types form an algebra over syntactic categories that is just
   // rich enough to let us recognize and propagate the constructs that
   // are either being counted in the preparser data, or is important
   // to throw the correct syntax error exceptions.
@@ skipping 545 matching lines @@
         }
         Expect(Token::RPAREN, CHECK_OK);
         result = this->ParseArrowFunctionLiteral(formals, formals_classifier,
                                                  CHECK_OK);
       } else {
         // Heuristically try to detect immediately called functions before
         // seeing the call parentheses.
         parenthesized_function_ = (peek() == Token::FUNCTION);
         result = this->ParseExpression(true, classifier, CHECK_OK);
         Expect(Token::RPAREN, CHECK_OK);
+        if (peek() == Token::ARROW) {
+          int x = 5;
+          USE(x);
+        }
       }
       break;
 
     case Token::CLASS: {
       BindingPatternUnexpectedToken(classifier);
       Consume(Token::CLASS);
       if (!allow_harmony_sloppy() && is_sloppy(language_mode())) {
         ReportMessage(MessageTemplate::kSloppyLexical);
         *ok = false;
         break;
@@ skipping 55 matching lines @@
 template <class Traits>
 typename ParserBase<Traits>::ExpressionT ParserBase<Traits>::ParseExpression(
     bool accept_IN, ExpressionClassifier* classifier, bool* ok) {
   // Expression ::
   //   AssignmentExpression
   //   Expression ',' AssignmentExpression
 
   ExpressionClassifier binding_classifier;
   ExpressionT result =
       this->ParseAssignmentExpression(accept_IN, &binding_classifier, CHECK_OK);
+  bool is_simple_parameter_list = this->IsIdentifier(result);
   classifier->Accumulate(binding_classifier,
                          ExpressionClassifier::AllProductions);
   bool seen_rest = false;
   while (peek() == Token::COMMA) {
     if (seen_rest) {
       // At this point the production can't possibly be valid, but we don't know
       // which error to signal.
       classifier->RecordArrowFormalParametersError(
           scanner()->peek_location(), MessageTemplate::kParamAfterRest);
     }
     Consume(Token::COMMA);
     bool is_rest = false;
     if (allow_harmony_rest_parameters() && peek() == Token::ELLIPSIS) {
       // 'x, y, ...z' in CoverParenthesizedExpressionAndArrowParameterList only
       // as the formal parameters of'(x, y, ...z) => foo', and is not itself a
       // valid expression or binding pattern.
       ExpressionUnexpectedToken(classifier);
       BindingPatternUnexpectedToken(classifier);
       Consume(Token::ELLIPSIS);
       seen_rest = is_rest = true;
     }
     int pos = position();
     ExpressionT right = this->ParseAssignmentExpression(
         accept_IN, &binding_classifier, CHECK_OK);
     if (is_rest) right = factory()->NewSpread(right, pos);
+    if (is_simple_parameter_list) {
+      is_simple_parameter_list = this->IsIdentifier(result);
+    }
     classifier->Accumulate(binding_classifier,
                            ExpressionClassifier::AllProductions);
     result = factory()->NewBinaryOperation(Token::COMMA, result, right, pos);
   }
+  if (!is_simple_parameter_list) {
+    classifier->RecordNonSimpleParameter();
+  }
   return result;
 }
 
 
 template <class Traits>
 typename ParserBase<Traits>::ExpressionT ParserBase<Traits>::ParseArrayLiteral(
     ExpressionClassifier* classifier, bool* ok) {
   // ArrayLiteral ::
   //   '[' Expression? (',' Expression?)* ']'
 
@@ skipping 415 matching lines @@
   ExpressionT expression = this->ParseConditionalExpression(
       accept_IN, &arrow_formals_classifier, CHECK_OK);
 
   if (allow_harmony_arrow_functions() && peek() == Token::ARROW) {
     BindingPatternUnexpectedToken(classifier);
     ValidateArrowFormalParameters(&arrow_formals_classifier, expression,
                                   parenthesized_formals, CHECK_OK);
     Scanner::Location loc(lhs_location.beg_pos, scanner()->location().end_pos);
     Scope* scope =
         this->NewScope(scope_, ARROW_SCOPE, FunctionKind::kArrowFunction);
+    bool is_simple = arrow_formals_classifier.is_simple_parameter_list();
+    if (!is_simple) scope->SetHasNonSimpleParameters();
     FormalParametersT parameters(scope);
+    parameters.is_simple = is_simple;
     checkpoint.Restore(&parameters.materialized_literals_count);
 
     scope->set_start_position(lhs_location.beg_pos);
     Scanner::Location duplicate_loc = Scanner::Location::invalid();
     this->ParseArrowFunctionFormalParameterList(&parameters, expression, loc,
                                                 &duplicate_loc, CHECK_OK);
     if (duplicate_loc.IsValid()) {
       arrow_formals_classifier.RecordDuplicateFormalParameterError(
           duplicate_loc);
     }
@@ skipping 901 matching lines @@
                                  formal_parameters.scope, kArrowFunction,
                                  &function_factory);
 
     function_state.SkipMaterializedLiterals(
         formal_parameters.materialized_literals_count);
 
     this->ReindexLiterals(formal_parameters);
 
     Expect(Token::ARROW, CHECK_OK);
 
+    // Arrow function formal parameters are parsed as StrictFormalParameterList,
+    // which is not the same as "parameters of a strict function"; it only means
+    // that duplicates are not allowed.  Of course, the arrow function may
+    // itself be strict as well.
+    const bool allow_duplicate_parameters = false;
+    this->ValidateFormalParameters(&formals_classifier, language_mode(),
+                                   allow_duplicate_parameters, CHECK_OK);
+
     if (peek() == Token::LBRACE) {
       // Multiple statement body
       Consume(Token::LBRACE);
       bool is_lazily_parsed =
           (mode() == PARSE_LAZILY && scope_->AllowsLazyCompilation());
       if (is_lazily_parsed) {
         body = this->NewStatementList(0, zone());
         this->SkipLazyFunctionBody(&materialized_literal_count,
                                    &expected_property_count, CHECK_OK);
       } else {
@@ skipping 15 matching lines @@
       body = this->NewStatementList(1, zone());
       this->AddParameterInitializationBlock(formal_parameters, body, CHECK_OK);
       body->Add(factory()->NewReturnStatement(expression, pos), zone());
       materialized_literal_count = function_state.materialized_literal_count();
       expected_property_count = function_state.expected_property_count();
     }
     super_loc = function_state.super_location();
 
     formal_parameters.scope->set_end_position(scanner()->location().end_pos);
 
-    // Arrow function formal parameters are parsed as StrictFormalParameterList,
-    // which is not the same as "parameters of a strict function"; it only means
-    // that duplicates are not allowed.  Of course, the arrow function may
-    // itself be strict as well.
-    const bool allow_duplicate_parameters = false;
-    this->ValidateFormalParameters(&formals_classifier, language_mode(),
-                                   allow_duplicate_parameters, CHECK_OK);
-
     // Validate strict mode.
     if (is_strict(language_mode())) {
       CheckStrictOctalLiteral(formal_parameters.scope->start_position(),
                               scanner()->location().end_pos, CHECK_OK);
     }
     if (is_strict(language_mode()) || allow_harmony_sloppy()) {
       this->CheckConflictingVarDeclarations(formal_parameters.scope, CHECK_OK);
     }
   }
 
@@ skipping 201 matching lines @@
       *ok = false;
       return;
     }
     has_seen_constructor_ = true;
     return;
   }
 }
 } }  // v8::internal
 
 #endif  // V8_PREPARSER_H