[class] Ban #constructor as a private field name

Bug: v8:5368
Change-Id: Idcb13e039614167da8b5be879e5644dbcb9df271
Reviewed-on: https://chromium-review.googlesource.com/899881Reviewed-by: Georg Neis <neis@chromium.org>
Commit-Queue: Sathya Gunasekaran <gsathya@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51128}

src/parsing/parser-base.h

@@ -1454,6 +1454,10 @@ class ParserBase {
       return this->scanner()->CurrentMatchesContextualEscaped(
           Token::CONSTRUCTOR);
     }
+    bool IsPrivateConstructor() {
+      return this->scanner()->CurrentMatchesContextualEscaped(
+          Token::PRIVATE_CONSTRUCTOR);
+    }
     bool IsPrototype() {
       return this->scanner()->CurrentMatchesContextualEscaped(Token::PROTOTYPE);
     }
@@ -2345,7 +2349,7 @@ ParserBase<Impl>::ParseClassPropertyDefinition(
           *ok = false;
           return impl()->NullLiteralProperty();
         }
-        if (!*is_computed_name && name_token != Token::PRIVATE_NAME) {
+        if (!*is_computed_name) {
           checker->CheckClassFieldName(*is_static,
                                        CHECK_OK_CUSTOM(NullLiteralProperty));
         }
@@ -6223,7 +6227,7 @@ void ParserBase<Impl>::ClassLiteralChecker::CheckClassFieldName(bool is_static,
     return;
   }
 
-  if (IsConstructor()) {
+  if (IsConstructor() || IsPrivateConstructor()) {
     this->parser()->ReportMessage(MessageTemplate::kConstructorClassField);
     *ok = false;
     return;

src/parsing/scanner.cc

@@ -1510,13 +1510,15 @@ uc32 Scanner::ScanUnicodeEscape() {
   KEYWORD_GROUP('y')                                        \
   KEYWORD("yield", Token::YIELD)                            \
   KEYWORD_GROUP('_')                                        \
-  KEYWORD("__proto__", Token::PROTO_UNDERSCORED)
+  KEYWORD("__proto__", Token::PROTO_UNDERSCORED)            \
+  KEYWORD_GROUP('#')                                        \
+  KEYWORD("#constructor", Token::PRIVATE_CONSTRUCTOR)
 
 static Token::Value KeywordOrIdentifierToken(const uint8_t* input,
                                              int input_length) {
   DCHECK_GE(input_length, 1);
   const int kMinLength = 2;
-  const int kMaxLength = 11;
+  const int kMaxLength = 12;
   if (input_length < kMinLength || input_length > kMaxLength) {
     return Token::IDENTIFIER;
   }

src/parsing/token.h

@@ -195,6 +195,7 @@ namespace internal {
   C(NAME, "name", 0)                                               \
   C(PROTO_UNDERSCORED, "__proto__", 0)                             \
   C(CONSTRUCTOR, "constructor", 0)                                 \
+  C(PRIVATE_CONSTRUCTOR, "#constructor", 0)                        \
   C(PROTOTYPE, "prototype", 0)                                     \
   C(EVAL, "eval", 0)                                               \
   C(ARGUMENTS, "arguments", 0)                                     \

test/cctest/test-parsing.cc

@@ -5129,6 +5129,9 @@ TEST(PrivateClassFieldsErrors) {
     "#async a = 0",
     "#async a",
 
+    "#constructor",
+    "#constructor = function() {}",
+
     "# a = 0",
     "#a() { }",
     "get #a() { }",

test/mjsunit/harmony/private-fields.js

@@ -11,8 +11,7 @@
 // (a) check private field access on proxies.
 // (b) throw reference error on missing private field access.
 // (c) throw when private fields are set without being declared.
-// (d) check that private field isn't called 'constructor'.
-// (e) tests involving eval
+// (d) tests involving eval
 {
   class C {
     #a;