Bug 1484373: Part 2b - Add cycle collection helpers for Tuple types. r=smaug

--HG--
extra : rebase_source : 268282522c8c217137974113416d26313b1c0249

xpcom/base/TupleCycleCollection.h

@@ -0,0 +1,35 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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/. */
+
+#ifndef TupleCycleCollection_h
+#define TupleCycleCollection_h
+
+#include "mozilla/Tuple.h"
+#include "nsCycleCollectionTraversalCallback.h"
+
+template<typename... Elements>
+inline void
+ImplCycleCollectionUnlink(mozilla::Tuple<Elements...>& aField)
+{
+  ForEach(aField, [](auto& aElem) {
+    ImplCycleCollectionUnlink(aElem);
+  });
+}
+
+template<typename... Elements>
+inline void
+ImplCycleCollectionTraverse(nsCycleCollectionTraversalCallback& aCallback,
+                            mozilla::Tuple<Elements...>& aField,
+                            const char* aName,
+                            uint32_t aFlags = 0)
+{
+  aFlags |= CycleCollectionEdgeNameArrayFlag;
+  ForEach(aField, [&](auto& aElem) {
+    ImplCycleCollectionTraverse(aCallback, aElem, aName, aFlags);
+  });
+}
+
+#endif // TupleCycleCollection_h

xpcom/base/moz.build

@@ -122,6 +122,7 @@ EXPORTS.mozilla += [
     'StaticMonitor.h',
     'StaticMutex.h',
     'StaticPtr.h',
+    'TupleCycleCollection.h',
 ]
 
 # nsDebugImpl isn't unified because we disable PGO so that NS_ABORT_OOM isn't