Symbol fixes (#1357)

Fix Symbol support so that typeof properly returns "symbol"

* fix an problem with typeof when used for symbols
* take care of SymbolKey before casting - this fixes some problems when adding new symbols to java classes mapped into the js engine

src/org/mozilla/javascript/NativeSymbol.java

@@ -67,7 +67,7 @@ private NativeSymbol(String desc) {
         this.symbolData = null;
     }
 
-    private NativeSymbol(SymbolKey key) {
+    NativeSymbol(SymbolKey key) {
         this.key = key;
         this.symbolData = this;
     }

src/org/mozilla/javascript/ScriptRuntime.java

@@ -1225,6 +1225,12 @@ public static Scriptable toObject(Context cx, Scriptable scope, Object val) {
         }
 
         if (isSymbol(val)) {
+            if (val instanceof SymbolKey) {
+                NativeSymbol result = new NativeSymbol((SymbolKey) val);
+                setBuiltinProtoAndParent(result, scope, TopLevel.Builtins.Symbol);
+                return result;
+            }
+
             NativeSymbol result = new NativeSymbol((NativeSymbol) val);
             setBuiltinProtoAndParent(result, scope, TopLevel.Builtins.Symbol);
             return result;
@@ -2864,6 +2870,7 @@ public static String typeof(Object value) {
         if (value instanceof BigInteger) return "bigint";
         if (value instanceof Number) return "number";
         if (value instanceof Boolean) return "boolean";
+        if (isSymbol(value)) return "symbol";
         throw errorWithClassName("msg.invalid.type", value);
     }
 

testsrc/jstests/es6/symbols.js

@@ -242,9 +242,8 @@ function TestCall() {
     assertTrue(symbols[i].getThisProto() === Symbol.prototype)
   }
 }
-// Rhino not sure what's up! TestCall()
+TestCall()
 
-/* Rhino no collections
 
 function TestCollections() {
   var set = new Set
@@ -269,7 +268,6 @@ function TestCollections() {
 }
 TestCollections()
 
-*/
 
 function TestKeySet(obj) {
   //assertTrue(%HasFastProperties(obj))
@@ -356,7 +354,6 @@ function TestKeyDelete(obj) {
 }
 
 
-/* Rhino no Map
 var objs = [{}, [], Object.create({}), Object(1), new Map, function(){}]
 
 for (var i in objs) {
@@ -371,7 +368,7 @@ for (var i in objs) {
   TestKeyDescriptor(obj)
   TestKeyDelete(obj)
 }
-*/
+
 
 function TestDefineProperties() {
   var properties = {}
@@ -567,7 +564,7 @@ function TestStringify(expected, input) {
                JSON.stringify(input, (key, value) => value, "="));
 }
 
-// Rhino TestStringify(undefined, Symbol("a"));
+TestStringify(undefined, Symbol("a"));
 TestStringify('[{}]', [Object(Symbol())]);
 var symbol_wrapper = Object(Symbol("a"))
 TestStringify('{}', symbol_wrapper);

testsrc/org/mozilla/javascript/tests/es6/Symbol3Test.java

@@ -0,0 +1,96 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.javascript.tests.es6;
+
+import static org.junit.Assert.assertEquals;
+
+import org.junit.Test;
+import org.mozilla.javascript.Context;
+import org.mozilla.javascript.ScriptableObject;
+import org.mozilla.javascript.SymbolKey;
+import org.mozilla.javascript.tests.Utils;
+
+/** Tests for Symbol support. */
+public class Symbol3Test {
+
+    @Test
+    public void scriptRuntimeTypeofSymbolKey() {
+        Utils.runWithAllOptimizationLevels(
+                cx -> {
+                    cx.setLanguageVersion(Context.VERSION_ES6);
+                    ScriptableObject scope = cx.initStandardObjects();
+
+                    String code =
+                            "function foo() {"
+                                    + "  var sym = Object.getOwnPropertySymbols(arguments);"
+                                    + "  return '' + sym.length + ' ' + typeof sym[0];"
+                                    + "}"
+                                    + "foo()";
+                    String result = (String) cx.evaluateString(scope, code, "test", 1, null);
+                    assertEquals("1 symbol", result);
+
+                    return null;
+                });
+    }
+
+    @Test
+    public void scriptRuntimeTypeofSymbol() {
+        Utils.runWithAllOptimizationLevels(
+                cx -> {
+                    cx.setLanguageVersion(Context.VERSION_ES6);
+                    ScriptableObject scope = cx.initStandardObjects();
+
+                    String result =
+                            (String)
+                                    cx.evaluateString(
+                                            scope, "typeof Symbol.toStringTag", "test", 1, null);
+                    assertEquals("symbol", result);
+
+                    return null;
+                });
+    }
+
+    @Test
+    public void symbolProperty() throws Exception {
+        Utils.runWithAllOptimizationLevels(
+                cx -> {
+                    cx.setLanguageVersion(Context.VERSION_ES6);
+                    ScriptableObject scope = cx.initStandardObjects();
+
+                    final String script =
+                            "var sym = Object.getOwnPropertySymbols(MyHostObject);"
+                                    + "var str = sym[0].toString();"
+                                    + "var result = sym[0].toString();"
+                                    + "result += ' ' + sym.length + ' ' + typeof sym[0];"
+                                    + "result += ' ' + MyHostObject[sym[0]]";
+
+                    try {
+                        final ScriptableObject jsObj = new MyHostObject();
+                        jsObj.setParentScope(scope);
+
+                        jsObj.defineProperty(
+                                SymbolKey.TO_STRING_TAG, "foo", ScriptableObject.DONTENUM);
+
+                        scope.put("MyHostObject", scope, jsObj);
+                    } catch (Exception e) {
+                    }
+
+                    final String result =
+                            (String) cx.evaluateString(scope, script, "myScript", 1, null);
+
+                    assertEquals("Symbol(Symbol.toStringTag) 1 symbol foo", result);
+
+                    return null;
+                });
+    }
+
+    public static class MyHostObject extends ScriptableObject {
+
+        @Override
+        public String getClassName() {
+            return "MyHostObject";
+        }
+    }
+}