Implement ES6 22.1.3.31 Array.prototype[@@unscopables]

This resolves #1587 and is an essential part of Unscopables.

3 files changed, 35 insertions, 4 deletions

diff --git a/js/src/jsarray.cpp b/js/src/jsarray.cpp
index a43afc437..7b33cd905 100644
--- a/js/src/jsarray.cpp
+++ b/js/src/jsarray.cpp
@@ -3291,6 +3291,32 @@ CreateArrayPrototype(JSContext* cx, JSProtoKey key)
     return arrayProto;
 }
 
+static bool
+array_proto_finish(JSContext* cx, JS::HandleObject ctor, JS::HandleObject proto)
+{
+    // Add Array.prototype[@@unscopables]. ECMA-262 6.0 22.1.3.31.
+    RootedObject unscopables(cx, NewObjectWithGivenProto<PlainObject>(cx, NullPtr(), NullPtr(), TenuredObject));
+    if (!unscopables)
+        return false;
+
+    RootedValue value(cx, BooleanValue(true));
+    if (!DefineProperty(cx, unscopables, cx->names().copyWithin, value) ||
+        !DefineProperty(cx, unscopables, cx->names().entries, value) ||
+        !DefineProperty(cx, unscopables, cx->names().fill, value) ||
+        !DefineProperty(cx, unscopables, cx->names().find, value) ||
+        !DefineProperty(cx, unscopables, cx->names().findIndex, value) ||
+        !DefineProperty(cx, unscopables, cx->names().includes, value) ||
+        !DefineProperty(cx, unscopables, cx->names().keys, value) ||
+        !DefineProperty(cx, unscopables, cx->names().values, value))
+    {
+        return false;
+    }
+
+    RootedId id(cx, SYMBOL_TO_JSID(cx->wellKnownSymbols().get(JS::SymbolCode::unscopables)));
+    value.setObject(*unscopables);
+    return DefineProperty(cx, proto, id, value, nullptr, nullptr, JSPROP_READONLY);
+}
+
 const Class ArrayObject::class_ = {
     "Array",
     JSCLASS_HAS_CACHED_PROTO(JSProto_Array),
@@ -3310,7 +3336,9 @@ const Class ArrayObject::class_ = {
         GenericCreateConstructor<js_Array, 1, JSFunction::FinalizeKind>,
         CreateArrayPrototype,
         array_static_methods,
-        array_methods
+        array_methods,
+        nullptr,
+        array_proto_finish
     }
 };
 
diff --git a/js/src/jsarray.h b/js/src/jsarray.h
index 4265f4386..4e471df77 100644
--- a/js/src/jsarray.h
+++ b/js/src/jsarray.h
@@ -33,9 +33,6 @@ js_IdIsIndex(jsid id, uint32_t* indexp)
     return js::StringIsArrayIndex(JSID_TO_ATOM(id), indexp);
 }
 
-extern JSObject*
-js_InitArrayClass(JSContext* cx, js::HandleObject obj);
-
 extern bool
 js_InitContextBusyArrayTable(JSContext* cx);
 
diff --git a/js/src/vm/CommonPropertyNames.h b/js/src/vm/CommonPropertyNames.h
index 87b9bc6a6..87b9ffdc0 100644
--- a/js/src/vm/CommonPropertyNames.h
+++ b/js/src/vm/CommonPropertyNames.h
@@ -44,6 +44,7 @@
     macro(construct, construct, "construct") \
     macro(constructor, constructor, "constructor") \
     macro(ConvertAndCopyTo, ConvertAndCopyTo, "ConvertAndCopyTo") \
+    macro(copyWithin, copyWithin, "copyWithin") \
     macro(count, count, "count") \
     macro(currency, currency, "currency") \
     macro(currencyDisplay, currencyDisplay, "currencyDisplay") \
@@ -67,6 +68,7 @@
     macro(emptyRegExp, emptyRegExp, "(?:)") \
     macro(encodeURI, encodeURI, "encodeURI") \
     macro(encodeURIComponent, encodeURIComponent, "encodeURIComponent") \
+    macro(entries, entries, "entries") \
     macro(enumerable, enumerable, "enumerable") \
     macro(enumerate, enumerate, "enumerate") \
     macro(escape, escape, "escape") \
@@ -75,6 +77,9 @@
     macro(fieldOffsets, fieldOffsets, "fieldOffsets") \
     macro(fieldTypes, fieldTypes, "fieldTypes") \
     macro(fileName, fileName, "fileName") \
+    macro(fill, fill, "fill") \
+    macro(find, find, "find") \
+    macro(findIndex, findIndex, "findIndex") \
     macro(fix, fix, "fix") \
     macro(float32, float32, "float32") \
     macro(float32x4, float32x4, "float32x4") \
@@ -97,6 +102,7 @@
     macro(hasOwnProperty, hasOwnProperty, "hasOwnProperty") \
     macro(ignoreCase, ignoreCase, "ignoreCase") \
     macro(ignorePunctuation, ignorePunctuation, "ignorePunctuation") \
+    macro(includes, includes, "includes") \
     macro(index, index, "index") \
     macro(InitializeCollator, InitializeCollator, "InitializeCollator") \
     macro(InitializeDateTimeFormat, InitializeDateTimeFormat, "InitializeDateTimeFormat") \