Remove kIsPossibleArrowFormals option from ParseAssignmentExpression

src/parsing/parser-base.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_PARSER_BASE_H
 #define V8_PARSING_PARSER_BASE_H
 
 #include "src/ast/scopes.h"
 #include "src/bailout-reason.h"
 #include "src/hashmap.h"
@@ skipping 710 matching lines @@
   IdentifierT ParseIdentifierName(bool* ok);
 
   ExpressionT ParseRegExpLiteral(bool seen_equal,
                                  ExpressionClassifier* classifier, bool* ok);
 
   ExpressionT ParsePrimaryExpression(ExpressionClassifier* classifier,
                                      bool* ok);
   ExpressionT ParseExpression(bool accept_IN, bool* ok);
   ExpressionT ParseExpression(bool accept_IN, ExpressionClassifier* classifier,
                               bool* ok);
-  ExpressionT ParseExpression(bool accept_IN, int flags,
-                              ExpressionClassifier* classifier, bool* ok);
   ExpressionT ParseArrayLiteral(ExpressionClassifier* classifier, bool* ok);
   ExpressionT ParsePropertyName(IdentifierT* name, bool* is_get, bool* is_set,
                                 bool* is_computed_name,
                                 ExpressionClassifier* classifier, bool* ok);
   ExpressionT ParseObjectLiteral(ExpressionClassifier* classifier, bool* ok);
   ObjectLiteralPropertyT ParsePropertyDefinition(
       ObjectLiteralCheckerBase* checker, bool in_class, bool has_extends,
       bool is_static, bool* is_computed_name, bool* has_seen_constructor,
       ExpressionClassifier* classifier, IdentifierT* name, bool* ok);
   typename Traits::Type::ExpressionList ParseArguments(
       Scanner::Location* first_spread_pos, ExpressionClassifier* classifier,
       bool* ok);
 
   enum AssignmentExpressionFlags {
-    kIsNormalAssignment = 0,
-    kIsPossiblePatternElement = 1 << 0,
-    kIsPossibleArrowFormals = 1 << 1
+    kIsNormalAssignment,
+    kIsPossiblePatternElement
   };
 
-  ExpressionT ParseAssignmentExpression(bool accept_IN, int flags,
+  ExpressionT ParseAssignmentExpression(bool accept_IN,
+                                        AssignmentExpressionFlags flags,
                                         ExpressionClassifier* classifier,
                                         bool* ok);
   ExpressionT ParseAssignmentExpression(bool accept_IN,
                                         ExpressionClassifier* classifier,
                                         bool* ok) {
     return ParseAssignmentExpression(accept_IN, kIsNormalAssignment, classifier,
                                      ok);
   }
   ExpressionT ParseYieldExpression(ExpressionClassifier* classifier, bool* ok);
   ExpressionT ParseConditionalExpression(bool accept_IN,
@@ skipping 557 matching lines @@
         return factory()->NewEmptyParentheses(beg_pos);
       } else if (Check(Token::ELLIPSIS)) {
         // (...x)=>x.  The continuation that looks for the => is in
         // ParseAssignmentExpression.
         int ellipsis_pos = position();
         int expr_pos = peek_position();
         classifier->RecordExpressionError(scanner()->location(),
                                           MessageTemplate::kUnexpectedToken,
                                           Token::String(Token::ELLIPSIS));
         classifier->RecordNonSimpleParameter();
-        ExpressionT expr = this->ParseAssignmentExpression(
-            true, kIsPossibleArrowFormals, classifier, CHECK_OK);
+        ExpressionT expr =
+            this->ParseAssignmentExpression(true, classifier, CHECK_OK);
         if (!this->IsIdentifier(expr) && !expr->IsObjectLiteral() &&
             !expr->IsArrayLiteral()) {
           classifier->RecordArrowFormalParametersError(
               Scanner::Location(ellipsis_pos, scanner()->location().end_pos),
               MessageTemplate::kInvalidRestParameter);
         }
         if (peek() == Token::COMMA) {
           ReportMessageAt(scanner()->peek_location(),
                           MessageTemplate::kParamAfterRest);
           *ok = false;
           return this->EmptyExpression();
         }
         Expect(Token::RPAREN, CHECK_OK);
         return factory()->NewSpread(expr, ellipsis_pos, expr_pos);
       }
       // Heuristically try to detect immediately called functions before
       // seeing the call parentheses.
       parenthesized_function_ = (peek() == Token::FUNCTION);
-      ExpressionT expr = this->ParseExpression(true, kIsPossibleArrowFormals,
-                                               classifier, CHECK_OK);
+      ExpressionT expr = this->ParseExpression(true, classifier, CHECK_OK);
       Expect(Token::RPAREN, CHECK_OK);
       return expr;
     }
 
     case Token::CLASS: {
       BindingPatternUnexpectedToken(classifier);
       Consume(Token::CLASS);
       if (!allow_harmony_sloppy() && is_sloppy(language_mode())) {
         ReportMessage(MessageTemplate::kSloppyLexical);
         *ok = false;
@@ skipping 49 matching lines @@
   ExpressionClassifier classifier;
   ExpressionT result = ParseExpression(accept_IN, &classifier, CHECK_OK);
   result = Traits::RewriteNonPattern(result, &classifier, CHECK_OK);
   return result;
 }
 
 
 template <class Traits>
 typename ParserBase<Traits>::ExpressionT ParserBase<Traits>::ParseExpression(
     bool accept_IN, ExpressionClassifier* classifier, bool* ok) {
-  return ParseExpression(accept_IN, kIsNormalAssignment, classifier, ok);
-}
-
-
-template <class Traits>
-typename ParserBase<Traits>::ExpressionT ParserBase<Traits>::ParseExpression(
-    bool accept_IN, int flags, ExpressionClassifier* classifier, bool* ok) {
   // Expression ::
   //   AssignmentExpression
   //   Expression ',' AssignmentExpression
 
   ExpressionClassifier binding_classifier;
-  ExpressionT result = this->ParseAssignmentExpression(
-      accept_IN, flags, &binding_classifier, CHECK_OK);
+  ExpressionT result =
+      this->ParseAssignmentExpression(accept_IN, &binding_classifier, CHECK_OK);
   classifier->Accumulate(binding_classifier,
                          ExpressionClassifier::AllProductions);
   bool is_simple_parameter_list = this->IsIdentifier(result);
   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 (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(), expr_pos = peek_position();
     ExpressionT right = this->ParseAssignmentExpression(
-        accept_IN, flags, &binding_classifier, CHECK_OK);
+        accept_IN, &binding_classifier, CHECK_OK);
     if (is_rest) {
       if (!this->IsIdentifier(right) && !right->IsObjectLiteral() &&
           !right->IsArrayLiteral()) {
         classifier->RecordArrowFormalParametersError(
             Scanner::Location(pos, scanner()->location().end_pos),
             MessageTemplate::kInvalidRestParameter);
       }
       right = factory()->NewSpread(right, pos, expr_pos);
     }
     is_simple_parameter_list =
@@ skipping 458 matching lines @@
     // the parser and preparser
     Traits::MaterializeUnspreadArgumentsLiterals(unspread_sequences_count);
   }
 
   return result;
 }
 
 // Precedence = 2
 template <class Traits>
 typename ParserBase<Traits>::ExpressionT
-ParserBase<Traits>::ParseAssignmentExpression(bool accept_IN, int flags,
+ParserBase<Traits>::ParseAssignmentExpression(bool accept_IN,
+                                              AssignmentExpressionFlags flags,
                                               ExpressionClassifier* classifier,
                                               bool* ok) {
   // AssignmentExpression ::
   //   ConditionalExpression
   //   ArrowFunction
   //   YieldExpression
   //   LeftHandSideExpression AssignmentOperator AssignmentExpression
-  bool maybe_pattern_element = flags & kIsPossiblePatternElement;
-  bool maybe_arrow_formals = flags & kIsPossibleArrowFormals;
+  bool maybe_pattern_element = flags == kIsPossiblePatternElement;
   bool is_destructuring_assignment = false;
   int lhs_beg_pos = peek_position();
 
   if (peek() == Token::YIELD && is_generator()) {
     return this->ParseYieldExpression(classifier, ok);
   }
 
   FuncNameInferrer::State fni_state(fni_);
   ParserBase<Traits>::Checkpoint checkpoint(this);
   ExpressionClassifier arrow_formals_classifier(classifier->duplicate_finder());
@@ skipping 67 matching lines @@
   if (!(allow_harmony_destructuring_bind() ||
         allow_harmony_default_parameters())) {
     BindingPatternUnexpectedToken(classifier);
   }
 
   if (allow_harmony_destructuring_assignment() && maybe_pattern &&
       peek() == Token::ASSIGN) {
     classifier->ForgiveCoverInitializedNameError();
     ValidateAssignmentPattern(classifier, CHECK_OK);
     is_destructuring_assignment = true;
-  } else if (maybe_arrow_formals) {
+  } else if (allow_harmony_default_parameters() &&
+             !allow_harmony_destructuring_assignment()) {
+    // TODO(adamk): This branch should be removed once the destructuring
+    // assignment and default parameter flags are removed.
     expression = this->ClassifyAndRewriteReferenceExpression(
         classifier, expression, lhs_beg_pos, scanner()->location().end_pos,
         MessageTemplate::kInvalidLhsInAssignment);
   } else {
     if (maybe_pattern_element) {
       CheckDestructuringElement(expression, classifier, lhs_beg_pos,
                                 scanner()->location().end_pos);
     }
     expression = this->CheckAndRewriteReferenceExpression(
         expression, lhs_beg_pos, scanner()->location().end_pos,
@@ skipping 1309 matching lines @@
       return;
     }
     has_seen_constructor_ = true;
     return;
   }
 }
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_PARSING_PARSER_BASE_H