Expose internal properties of map/set iterators via mirrors.

src/runtime/runtime-collections.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #include "src/arguments.h"
 #include "src/runtime/runtime-utils.h"
 
 
@@ skipping 97 matching lines @@
 
 RUNTIME_FUNCTION(Runtime_SetIteratorNext) {
   SealHandleScope shs(isolate);
   DCHECK(args.length() == 2);
   CONVERT_ARG_CHECKED(JSSetIterator, holder, 0);
   CONVERT_ARG_CHECKED(JSArray, value_array, 1);
   return holder->Next(value_array);
 }
 
 
+// The array returned contains the following information:
+// 0: HasMore flag
+// 1: Iteration index
+// 2: Iteration kind
+RUNTIME_FUNCTION(Runtime_SetIteratorDetails) {
+  HandleScope scope(isolate);
+  DCHECK(args.length() == 1);
+  CONVERT_ARG_HANDLE_CHECKED(JSSetIterator, holder, 0);
+  Handle<FixedArray> details = isolate->factory()->NewFixedArray(4);
+  details->set(0, isolate->heap()->ToBoolean(holder->HasMore()));
+  details->set(1, holder->index());
+  details->set(2, holder->kind());
+  return *isolate->factory()->NewJSArrayWithElements(details);
+}
+
+
 RUNTIME_FUNCTION(Runtime_MapInitialize) {
   HandleScope scope(isolate);
   DCHECK(args.length() == 1);
   CONVERT_ARG_HANDLE_CHECKED(JSMap, holder, 0);
   Handle<OrderedHashMap> table = isolate->factory()->NewOrderedHashMap();
   holder->set_table(*table);
   return *holder;
 }
 
 
@@ skipping 90 matching lines @@
 
   Handle<JSMapIterator> result = isolate->factory()->NewJSMapIterator();
   result->set_table(holder->table());
   result->set_index(Smi::FromInt(Smi::cast(holder->index())->value()));
   result->set_kind(Smi::FromInt(Smi::cast(holder->kind())->value()));
 
   return *result;
 }
 
 
+// The array returned contains the following information:
+// 0: HasMore flag
+// 1: Iteration index
+// 2: Iteration kind
+RUNTIME_FUNCTION(Runtime_MapIteratorDetails) {
+  HandleScope scope(isolate);
+  DCHECK(args.length() == 1);
+  CONVERT_ARG_HANDLE_CHECKED(JSMapIterator, holder, 0);
+  Handle<FixedArray> details = isolate->factory()->NewFixedArray(4);
+  details->set(0, isolate->heap()->ToBoolean(holder->HasMore()));
+  details->set(1, holder->index());
+  details->set(2, holder->kind());
+  return *isolate->factory()->NewJSArrayWithElements(details);
+}
+
+
 RUNTIME_FUNCTION(Runtime_GetWeakMapEntries) {
   HandleScope scope(isolate);
   DCHECK(args.length() == 2);
   CONVERT_ARG_HANDLE_CHECKED(JSWeakCollection, holder, 0);
   CONVERT_NUMBER_CHECKED(int, max_entries, Int32, args[1]);
   RUNTIME_ASSERT(max_entries >= 0);
 
   Handle<ObjectHashTable> table(ObjectHashTable::cast(holder->table()));
   if (max_entries == 0 || max_entries > table->NumberOfElements()) {
     max_entries = table->NumberOfElements();
@@ skipping 144 matching lines @@
   // isolate. If it's called more often, the map should be moved into the
   // strong root list.
   Handle<Map> map =
       isolate->factory()->NewMap(JS_WEAK_MAP_TYPE, JSWeakMap::kSize);
   Handle<JSWeakMap> weakmap =
       Handle<JSWeakMap>::cast(isolate->factory()->NewJSObjectFromMap(map));
   return *WeakCollectionInitialize(isolate, weakmap);
 }
 }
 }  // namespace v8::internal