Classes: Implement correct name binding

src/parser.cc

Index: src/parser.cc
diff --git a/src/parser.cc b/src/parser.cc
index 99c93b88faffa57bcf087fdac07ad9010688cafa..b2cf3b1a6d385ee7d79b9b46bcda1dc2dd209346 100644
--- a/src/parser.cc
+++ b/src/parser.cc
@@ -685,13 +685,6 @@ Expression* ParserTraits::SuperReference(Scope* scope, AstNodeFactory* factory,
       pos);
 }
 
-Expression* ParserTraits::ClassExpression(
-    const AstRawString* name, Expression* extends, Expression* constructor,
-    ZoneList<ObjectLiteral::Property*>* properties, int start_position,
-    int end_position, AstNodeFactory* factory) {
-  return factory->NewClassLiteral(name, extends, constructor, properties,
-                                  start_position, end_position);
-}
 
 Expression* ParserTraits::DefaultConstructor(bool call_super, Scope* scope,
                                              int pos, int end_pos) {
@@ -777,6 +770,14 @@ FunctionLiteral* ParserTraits::ParseFunctionLiteral(
 }
 
 
+ClassLiteral* ParserTraits::ParseClassLiteral(
+    const AstRawString* name, Scanner::Location class_name_location,
+    bool name_is_strict_reserved, int pos, bool* ok) {
+  return parser_->ParseClassLiteral(name, class_name_location,
+                                    name_is_strict_reserved, pos, ok);
+}
+
+
 Parser::Parser(CompilationInfo* info, ParseInfo* parse_info)
     : ParserBase<ParserTraits>(&scanner_, parse_info->stack_limit,
                                info->extension(), NULL, info->zone(), this),
@@ -1993,8 +1994,8 @@ Statement* Parser::ParseClassDeclaration(ZoneList<const AstRawString*>* names,
   bool is_strict_reserved = false;
   const AstRawString* name =
       ParseIdentifierOrStrictReservedWord(&is_strict_reserved, CHECK_OK);
-  Expression* value = ParseClassLiteral(name, scanner()->location(),
-                                        is_strict_reserved, pos, CHECK_OK);
+  ClassLiteral* value = ParseClassLiteral(name, scanner()->location(),
+                                          is_strict_reserved, pos, CHECK_OK);
 
   VariableProxy* proxy = NewUnresolved(name, LET, Interface::NewValue());
   Declaration* declaration =
@@ -3893,6 +3894,90 @@ PreParser::PreParseResult Parser::ParseLazyFunctionBodyWithPreParser(
 }
 
 
+ClassLiteral* Parser::ParseClassLiteral(const AstRawString* name,

[marja, 2015/02/10 11:31:49]

Is there a reason why ParseClassLiteral is not in ParserBase, but both in Parser
and PreParser (so that there are 2 versions of it)? Is something missing in the
PreParser? Is there some mess in the code that makes it hard?

All other Expression parsing is unified (so, implemented only once, in
ParserBase), so this is moving the situation backwards...

+                                        Scanner::Location class_name_location,
+                                        bool name_is_strict_reserved, int pos,
+                                        bool* ok) {
+  // All parts of a ClassDeclaration and ClassExpression are strict code.
+  if (name_is_strict_reserved) {
+    ReportMessageAt(class_name_location, "unexpected_strict_reserved");
+    *ok = false;
+    return NULL;
+  }
+  if (IsEvalOrArguments(name)) {
+    ReportMessageAt(class_name_location, "strict_eval_arguments");
+    *ok = false;
+    return NULL;
+  }
+
+  Scope* block_scope = NewScope(scope_, BLOCK_SCOPE);
+  BlockState block_state(&scope_, block_scope);
+  scope_->SetStrictMode(STRICT);
+  scope_->SetScopeName(name);
+
+  VariableProxy* proxy = NULL;
+  if (name != NULL) {
+    proxy = NewUnresolved(name, CONST, Interface::NewConst());
+    Declaration* declaration =
+        factory()->NewVariableDeclaration(proxy, CONST, block_scope, pos);
+    Declare(declaration, true, CHECK_OK);
+  }
+
+  Expression* extends = NULL;
+  if (Check(Token::EXTENDS)) {
+    block_scope->set_start_position(scanner()->location().end_pos);
+    extends = ParseLeftHandSideExpression(CHECK_OK);
+  } else {
+    block_scope->set_start_position(scanner()->location().end_pos);
+  }
+
+  ZoneList<ObjectLiteral::Property*>* properties = NewPropertyList(4, zone());
+  Expression* constructor = NULL;
+  bool has_seen_constructor = false;
+
+  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;
+    ObjectLiteral::Property* property = ParsePropertyDefinition(
+        NULL, in_class, is_static, &has_seen_constructor, CHECK_OK);
+
+    if (has_seen_constructor && constructor == NULL) {
+      constructor = GetPropertyValue(property);
+    } else {
+      properties->Add(property, zone());
+    }
+
+    if (fni_ != NULL) {
+      fni_->Infer();
+      fni_->Leave();
+    }
+  }
+
+  Expect(Token::RBRACE, CHECK_OK);
+  int end_pos = scanner()->location().end_pos;
+
+  if (constructor == NULL) {
+    constructor =
+        DefaultConstructor(extends != NULL, block_scope, pos, end_pos);
+  }
+
+  block_scope->set_end_position(end_pos);
+  block_scope = block_scope->FinalizeBlockScope();
+
+  if (name != NULL) {
+    DCHECK_NOT_NULL(proxy);
+    DCHECK_NOT_NULL(block_scope);
+    proxy->var()->set_initializer_position(end_pos);
+  }
+
+  return factory()->NewClassLiteral(name, block_scope, proxy, extends,
+                                    constructor, properties, pos, end_pos);
+}
+
+
 Expression* Parser::ParseV8Intrinsic(bool* ok) {
   // CallRuntime ::
   //   '%' Identifier Arguments