Classes runtime

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 132 matching lines @@
   // The parser's current scope is in scope_. BlockState and FunctionState
   // constructors push on the scope stack and the destructors pop. They are also
   // used to hold the parser's per-function and per-block state.
   class BlockState BASE_EMBEDDED {
    public:
     BlockState(typename Traits::Type::Scope** scope_stack,
                typename Traits::Type::Scope* scope)
         : scope_stack_(scope_stack),
           outer_scope_(*scope_stack),
           scope_(scope) {
       *scope_stack_ = scope_;

[Dmitry Lomov (no reviews), 2014/10/07 10:28:32]

Why do you need this constructor?

[arv (Not doing code reviews), 2014/10/07 14:47:09]

This is due to how parser and preparser typedef Scope differently.

We have the same duplication of the constructor for FunctionState.

[Dmitry Lomov (no reviews), 2014/10/07 15:09:37]

Could we investigate the possibility of removing this discrepancy between
prepaser and parser? This is very confusing (not necessarily in this CL)

[arv (Not doing code reviews), 2014/10/07 15:16:52]

I agree that this is confusing. I struggled quite a bit to understand what was
going on here.

     }
+    BlockState(typename Traits::Type::Scope** scope_stack,
+               typename Traits::Type::Scope** scope)
+        : scope_stack_(scope_stack),
+          outer_scope_(*scope_stack),
+          scope_(*scope) {
+      *scope_stack_ = scope_;
+    }
     ~BlockState() { *scope_stack_ = outer_scope_; }
 
    private:
     typename Traits::Type::Scope** scope_stack_;
     typename Traits::Type::Scope* outer_scope_;
     typename Traits::Type::Scope* scope_;
   };
 
   class FunctionState BASE_EMBEDDED {
    public:
@@ skipping 1017 matching lines @@
 
   static bool IsBoilerplateProperty(PreParserExpression property) {
     // PreParser doesn't count boilerplate properties.
     return false;
   }
 
   static bool IsArrayIndex(PreParserIdentifier string, uint32_t* index) {
     return false;
   }
 
+  bool IsConstructorProperty(PreParserExpression property) { return false; }
+
+  static PreParserExpression GetPropertyValue(PreParserExpression property) {
+    UNREACHABLE();
+    return PreParserExpression::Default();
+  }
+
   // Functions for encapsulating the differences between parsing and preparsing;
   // operations interleaved with the recursive descent.
   static void PushLiteralName(FuncNameInferrer* fni, PreParserIdentifier id) {
     // PreParser should not use FuncNameInferrer.
     UNREACHABLE();
   }
   static void PushPropertyName(FuncNameInferrer* fni,
                                PreParserExpression expression) {
     // PreParser should not use FuncNameInferrer.
     UNREACHABLE();
@@ skipping 105 matching lines @@
   static PreParserExpression ThisExpression(PreParserScope* scope,
                                             PreParserFactory* factory) {
     return PreParserExpression::This();
   }
 
   static PreParserExpression SuperReference(PreParserScope* scope,
                                             PreParserFactory* factory) {
     return PreParserExpression::Super();
   }
 
-  static PreParserExpression ClassLiteral(PreParserIdentifier name,
-                                          PreParserExpression extends,
-                                          PreParserExpression constructor,
-                                          PreParserExpressionList properties,
-                                          int position,
-                                          PreParserFactory* factory) {
+  static PreParserExpression ClassExpression(PreParserIdentifier name,
+                                             PreParserExpression extends,
+                                             PreParserExpression constructor,
+                                             PreParserExpressionList properties,
+                                             int position,
+                                             PreParserFactory* factory) {
     return PreParserExpression::Default();
   }
 
   static PreParserExpression ExpressionFromLiteral(
       Token::Value token, int pos, Scanner* scanner,
       PreParserFactory* factory) {
     return PreParserExpression::Default();
   }
 
   static PreParserExpression ExpressionFromIdentifier(
@@ skipping 632 matching lines @@
 
   } else if (is_generator ||
              (allow_harmony_object_literals_ && peek() == Token::LPAREN)) {
     // Concise Method
 
     if (is_static && this->IsPrototype(name)) {
       ReportMessageAt(scanner()->location(), "static_prototype");
       *ok = false;
       return this->EmptyObjectLiteralProperty();
     }
-    if (is_generator && in_class && !is_static && this->IsConstructor(name)) {
-      ReportMessageAt(scanner()->location(), "constructor_special_method");
-      *ok = false;
-      return this->EmptyObjectLiteralProperty();
-    }
 
-    checker->CheckProperty(name_token, kValueProperty,
-                           CHECK_OK_CUSTOM(EmptyObjectLiteralProperty));
     FunctionKind kind = is_generator ? FunctionKind::kConciseGeneratorMethod
                                      : FunctionKind::kConciseMethod;
 
+    if (in_class && !is_static && this->IsConstructor(name)) {
+      if (is_generator) {
+        ReportMessageAt(scanner()->location(), "constructor_special_method");
+        *ok = false;
+        return this->EmptyObjectLiteralProperty();
+      }
+
+      kind = FunctionKind::kConstructorMethod;
+    }
+
+    checker->CheckProperty(name_token, kValueProperty,
+                           CHECK_OK_CUSTOM(EmptyObjectLiteralProperty));
+
     value = this->ParseFunctionLiteral(
         name, scanner()->location(),
         false,  // reserved words are allowed here
         kind, RelocInfo::kNoPosition, FunctionLiteral::ANONYMOUS_EXPRESSION,
         FunctionLiteral::NORMAL_ARITY,
         CHECK_OK_CUSTOM(EmptyObjectLiteralProperty));
 
   } else if (in_class && name_is_static && !is_static) {
     // static MethodDefinition
     return ParsePropertyDefinition(checker, true, true, ok);
@@ skipping 736 matching lines @@
     ReportMessageAt(class_name_location, "unexpected_strict_reserved");
     *ok = false;
     return this->EmptyExpression();
   }
   if (this->IsEvalOrArguments(name)) {
     ReportMessageAt(class_name_location, "strict_eval_arguments");
     *ok = false;
     return this->EmptyExpression();
   }
 
+  ExpressionT extends = this->EmptyExpression();
+  if (Check(Token::EXTENDS)) {
+    typename Traits::Type::ScopePtr scope = this->NewScope(scope_, BLOCK_SCOPE);
+    BlockState block_state(&scope_, &scope);

[Dmitry Lomov (no reviews), 2014/10/07 10:28:32]

Seems like BlockState block_state(&scope_, scope) will do just fine here.

[arv (Not doing code reviews), 2014/10/07 14:47:09]

That works with PreParser but not with Parser.

+    scope_->SetStrictMode(STRICT);
+    extends = this->ParseLeftHandSideExpression(CHECK_OK);
+  }
+
   // TODO(arv): Implement scopes and name binding in class body only.
-  // TODO(arv): Maybe add CLASS_SCOPE?
-  typename Traits::Type::ScopePtr extends_scope =
-      this->NewScope(scope_, BLOCK_SCOPE);
-  FunctionState extends_function_state(
-      &function_state_, &scope_, &extends_scope, zone(),
-      this->ast_value_factory(), ast_node_id_gen_);
+  typename Traits::Type::ScopePtr scope = this->NewScope(scope_, BLOCK_SCOPE);
+  BlockState block_state(&scope_, &scope);
   scope_->SetStrictMode(STRICT);
   scope_->SetScopeName(name);
 
-  ExpressionT extends = this->EmptyExpression();
-  if (Check(Token::EXTENDS)) {
-    extends = this->ParseLeftHandSideExpression(CHECK_OK);
-  }
-
   ObjectLiteralChecker checker(this, STRICT);
   typename Traits::Type::PropertyList properties =
       this->NewPropertyList(4, zone_);
-  FunctionLiteralT constructor = this->EmptyFunctionLiteral();
+  ExpressionT constructor = this->EmptyExpression();
 
   Expect(Token::LBRACE, CHECK_OK);
   while (peek() != Token::RBRACE) {
     if (Check(Token::SEMICOLON)) continue;
     if (fni_ != NULL) fni_->Enter();
 
     const bool in_class = true;
     const bool is_static = false;
     ObjectLiteralPropertyT property =
         this->ParsePropertyDefinition(&checker, in_class, is_static, CHECK_OK);
 
-    properties->Add(property, zone());
+    if (this->IsConstructorProperty(property)) {
+      constructor = this->GetPropertyValue(property);
+    } else {
+      properties->Add(property, zone());
+    }
 
     if (fni_ != NULL) {
       fni_->Infer();
       fni_->Leave();
     }
   }
   Expect(Token::RBRACE, CHECK_OK);
 
-  return this->ClassLiteral(name, extends, constructor, properties, pos,
-                            factory());
+  return this->ClassExpression(name, extends, constructor, properties, pos,
+                               factory());
 }
 
 
 template <typename Traits>
 typename ParserBase<Traits>::ExpressionT
 ParserBase<Traits>::CheckAndRewriteReferenceExpression(
     ExpressionT expression,
     Scanner::Location location, const char* message, bool* ok) {
   if (strict_mode() == STRICT && this->IsIdentifier(expression) &&
       this->IsEvalOrArguments(this->AsIdentifier(expression))) {
@@ skipping 42 matching lines @@
       DCHECK(IsAccessorAccessorConflict(old_type, type));
       // Both accessors of the same type.
       parser()->ReportMessage("accessor_get_set");
     }
     *ok = false;
   }
 }
 } }  // v8::internal
 
 #endif  // V8_PREPARSER_H