From 6704bbce826a95ccf5f9043fef60899c8f596a28 Mon Sep 17 00:00:00 2001
From: "rossberg@chromium.org"
 <rossberg@chromium.org@ce2b1a6d-e550-0410-aec6-3dcde31c8c00>
Date: Mon, 24 Mar 2014 15:45:52 +0000
Subject: [PATCH] Spec adjustments for well-known symbols

R=arv@chromium.org, mstarzinger@chromium.org
BUG=

Review URL: https://codereview.chromium.org/208423013

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@20204 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
---
 src/symbol.js                   | 37 +++++++++++++++++----------------
 test/mjsunit/harmony/symbols.js | 27 +++++++++++++++++++-----
 2 files changed, 41 insertions(+), 23 deletions(-)

diff --git a/src/symbol.js b/src/symbol.js
index 49f909694c..7bf10d1288 100644
--- a/src/symbol.js
+++ b/src/symbol.js
@@ -65,7 +65,7 @@ function SymbolValueOf() {
 
 function GetSymbolRegistry() {
   var registry = %SymbolRegistry();
-  if (!('internal' in registry)) {
+  if (IS_UNDEFINED(registry.internal)) {
     registry.internal = {__proto__: null};
     registry.for = {__proto__: null};
     registry.keyFor = {__proto__: null};
@@ -76,7 +76,7 @@ function GetSymbolRegistry() {
 
 function InternalSymbol(key) {
   var registry = GetSymbolRegistry();
-  if (!(key in registry.internal)) {
+  if (IS_UNDEFINED(registry.internal[key])) {
     registry.internal[key] = %CreateSymbol(key);
   }
   return registry.internal[key];
@@ -86,7 +86,7 @@ function InternalSymbol(key) {
 function SymbolFor(key) {
   key = TO_STRING_INLINE(key);
   var registry = GetSymbolRegistry();
-  if (!(key in registry.for)) {
+  if (IS_UNDEFINED(registry.for[key])) {
     var symbol = %CreateSymbol(key);
     registry.for[key] = symbol;
     registry.keyFor[symbol] = key;
@@ -118,13 +118,13 @@ function ObjectGetOwnPropertySymbols(obj) {
 
 //-------------------------------------------------------------------
 
-var symbolCreate = InternalSymbol("@@create");
-var symbolHasInstance = InternalSymbol("@@hasInstance");
-var symbolIsConcatSpreadable = InternalSymbol("@@isConcatSpreadable");
-var symbolIsRegExp = InternalSymbol("@@isRegExp");
-var symbolIterator = InternalSymbol("@@iterator");
-var symbolToStringTag = InternalSymbol("@@toStringTag");
-var symbolUnscopables = InternalSymbol("@@unscopables");
+var symbolCreate = InternalSymbol("Symbol.create");
+var symbolHasInstance = InternalSymbol("Symbol.hasInstance");
+var symbolIsConcatSpreadable = InternalSymbol("Symbol.isConcatSpreadable");
+var symbolIsRegExp = InternalSymbol("Symbol.isRegExp");
+var symbolIterator = InternalSymbol("Symbol.iterator");
+var symbolToStringTag = InternalSymbol("Symbol.toStringTag");
+var symbolUnscopables = InternalSymbol("Symbol.unscopables");
 
 
 //-------------------------------------------------------------------
@@ -135,14 +135,15 @@ function SetUpSymbol() {
   %SetCode($Symbol, SymbolConstructor);
   %FunctionSetPrototype($Symbol, new $Object());
 
-  %SetProperty($Symbol, "create", symbolCreate, DONT_ENUM);
-  %SetProperty($Symbol, "hasInstance", symbolHasInstance, DONT_ENUM);
-  %SetProperty($Symbol, "isConcatSpreadable",
-      symbolIsConcatSpreadable, DONT_ENUM);
-  %SetProperty($Symbol, "isRegExp", symbolIsRegExp, DONT_ENUM);
-  %SetProperty($Symbol, "iterator", symbolIterator, DONT_ENUM);
-  %SetProperty($Symbol, "toStringTag", symbolToStringTag, DONT_ENUM);
-  %SetProperty($Symbol, "unscopables", symbolUnscopables, DONT_ENUM);
+  InstallConstants($Symbol, $Array(
+    "create", symbolCreate,
+    "hasInstance", symbolHasInstance,
+    "isConcatSpreadable", symbolIsConcatSpreadable,
+    "isRegExp", symbolIsRegExp,
+    "iterator", symbolIterator,
+    "toStringTag", symbolToStringTag,
+    "unscopables", symbolUnscopables
+  ));
   InstallFunctions($Symbol, DONT_ENUM, $Array(
     "for", SymbolFor,
     "keyFor", SymbolKeyFor
diff --git a/test/mjsunit/harmony/symbols.js b/test/mjsunit/harmony/symbols.js
index d19aece5b1..e7bf360406 100644
--- a/test/mjsunit/harmony/symbols.js
+++ b/test/mjsunit/harmony/symbols.js
@@ -410,12 +410,29 @@ function TestGetOwnPropertySymbolsWithProto() {
 TestGetOwnPropertySymbolsWithProto()
 
 
-function TestRegistry() {
-  assertFalse(Symbol.for("@@create") === Symbol.create)
-  assertFalse(Symbol.for("@@iterator") === Symbol.iterator)
-  assertTrue(Symbol.keyFor(Symbol.create) === undefined)
-  assertTrue(Symbol.keyFor(Symbol.iterator) === undefined)
+function TestWellKnown() {
+  var symbols = [
+    "create", "hasInstance", "isConcatSpreadable", "isRegExp",
+    "iterator", "toStringTag", "unscopables"
+  ]
 
+  for (var i in symbols) {
+    var name = symbols[i]
+    var desc = Object.getOwnPropertyDescriptor(Symbol, name)
+    assertSame("symbol", typeof desc.value)
+    assertSame("Symbol(Symbol." + name + ")", desc.value.toString())
+    assertFalse(desc.writable)
+    assertFalse(desc.configurable)
+    assertFalse(desc.enumerable)
+
+    assertFalse(Symbol.for("Symbol." + name) === desc.value)
+    assertTrue(Symbol.keyFor(desc.value) === undefined)
+  }
+}
+TestWellKnown()
+
+
+function TestRegistry() {
   var symbol1 = Symbol.for("x1")
   var symbol2 = Symbol.for("x2")
   assertFalse(symbol1 === symbol2)