1 files changed, 79 insertions, 0 deletions
diff --git a/xpcom/ds/nsSimpleEnumerator.cpp b/xpcom/ds/nsSimpleEnumerator.cpp
new file mode 100644
index 0000000000..0be7b684b7
--- /dev/null
+++ b/xpcom/ds/nsSimpleEnumerator.cpp
@@ -0,0 +1,79 @@
+/* -*- 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/. */
+
+#include "nsSimpleEnumerator.h"
+
+#include "mozilla/dom/IteratorResultBinding.h"
+#include "mozilla/dom/RootedDictionary.h"
+#include "mozilla/dom/ToJSValue.h"
+#include "mozilla/ResultExtensions.h"
+#include "mozilla/Try.h"
+#include "nsContentUtils.h"
+
+using namespace mozilla;
+using namespace mozilla::dom;
+
+namespace {
+
+class JSEnumerator final : public nsIJSEnumerator {
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSIJSENUMERATOR
+
+  explicit JSEnumerator(nsISimpleEnumerator* aEnumerator, const nsID& aIID)
+      : mEnumerator(aEnumerator), mIID(aIID) {}
+
+ private:
+  ~JSEnumerator() = default;
+
+  nsCOMPtr<nsISimpleEnumerator> mEnumerator;
+  const nsID mIID;
+};
+
+}  // anonymous namespace
+
+nsresult JSEnumerator::Iterator(nsIJSEnumerator** aResult) {
+  RefPtr<JSEnumerator> result(this);
+  result.forget(aResult);
+  return NS_OK;
+}
+
+nsresult JSEnumerator::Next(JSContext* aCx, JS::MutableHandleValue aResult) {
+  RootedDictionary<IteratorResult> result(aCx);
+
+  nsCOMPtr<nsISupports> elem;
+  if (NS_FAILED(mEnumerator->GetNext(getter_AddRefs(elem)))) {
+    result.mDone = true;
+  } else {
+    result.mDone = false;
+
+    JS::RootedValue value(aCx);
+    MOZ_TRY(nsContentUtils::WrapNative(aCx, elem, &mIID, &value));
+    result.mValue = value;
+  }
+
+  if (!ToJSValue(aCx, result, aResult)) {
+    return NS_ERROR_OUT_OF_MEMORY;
+  }
+  return NS_OK;
+}
+
+NS_IMPL_ISUPPORTS(JSEnumerator, nsIJSEnumerator)
+
+nsresult nsSimpleEnumerator::Iterator(nsIJSEnumerator** aResult) {
+  auto result = MakeRefPtr<JSEnumerator>(this, DefaultInterface());
+  result.forget(aResult);
+  return NS_OK;
+}
+
+nsresult nsSimpleEnumerator::Entries(const nsIID& aIface,
+                                     nsIJSEnumerator** aResult) {
+  auto result = MakeRefPtr<JSEnumerator>(this, aIface);
+  result.forget(aResult);
+  return NS_OK;
+}
+
+NS_IMPL_ISUPPORTS(nsSimpleEnumerator, nsISimpleEnumerator,
+                  nsISimpleEnumeratorBase)