1 files changed, 85 insertions, 0 deletions
diff --git a/dom/bindings/Record.h b/dom/bindings/Record.h
new file mode 100644
index 0000000000..1c9145a40d
--- /dev/null
+++ b/dom/bindings/Record.h
@@ -0,0 +1,85 @@
+/* -*- 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/. */
+
+/**
+ * Class for representing record arguments.  Basically an array under the hood.
+ */
+
+#ifndef mozilla_dom_Record_h
+#define mozilla_dom_Record_h
+
+#include <utility>
+
+#include "mozilla/Attributes.h"
+#include "nsHashKeys.h"
+#include "nsString.h"
+#include "nsTArray.h"
+#include "nsTHashtable.h"
+
+namespace mozilla::dom {
+
+namespace binding_detail {
+template <typename KeyType, typename ValueType>
+class RecordEntry {
+ public:
+  RecordEntry() = default;
+
+  // Move constructor so we can do Records of Records.
+  RecordEntry(RecordEntry<KeyType, ValueType>&& aOther)
+      : mKey(std::move(aOther.mKey)), mValue(std::move(aOther.mValue)) {}
+
+  KeyType mKey;
+  ValueType mValue;
+};
+
+// Specialize for a JSObject* ValueType and initialize it on construction, so we
+// don't need to worry about un-initialized JSObject* floating around.
+template <typename KeyType>
+class RecordEntry<KeyType, JSObject*> {
+ public:
+  RecordEntry() : mValue(nullptr) {}
+
+  // Move constructor so we can do Records of Records.
+  RecordEntry(RecordEntry<KeyType, JSObject*>&& aOther)
+      : mKey(std::move(aOther.mKey)), mValue(std::move(aOther.mValue)) {}
+
+  KeyType mKey;
+  JSObject* mValue;
+};
+
+}  // namespace binding_detail
+
+template <typename KeyType, typename ValueType>
+class Record {
+ public:
+  typedef typename binding_detail::RecordEntry<KeyType, ValueType> EntryType;
+  typedef Record<KeyType, ValueType> SelfType;
+
+  Record() = default;
+
+  // Move constructor so we can do Record of Record.
+  Record(SelfType&& aOther) : mEntries(std::move(aOther.mEntries)) {}
+
+  const nsTArray<EntryType>& Entries() const { return mEntries; }
+
+  nsTArray<EntryType>& Entries() { return mEntries; }
+
+ private:
+  nsTArray<EntryType> mEntries;
+};
+
+}  // namespace mozilla::dom
+
+template <typename K, typename V>
+class nsDefaultComparator<mozilla::dom::binding_detail::RecordEntry<K, V>, K> {
+ public:
+  bool Equals(const mozilla::dom::binding_detail::RecordEntry<K, V>& aEntry,
+              const K& aKey) const {
+    return aEntry.mKey == aKey;
+  }
+};
+
+#endif  // mozilla_dom_Record_h