1 files changed, 84 insertions, 0 deletions
diff --git a/dom/base/DOMStringList.h b/dom/base/DOMStringList.h
new file mode 100644
index 0000000000..89bb9fc418
--- /dev/null
+++ b/dom/base/DOMStringList.h
@@ -0,0 +1,84 @@
+/* -*- 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 mozilla_dom_DOMStringList_h
+#define mozilla_dom_DOMStringList_h
+
+#include "nsISupports.h"
+#include "nsTArray.h"
+#include "nsWrapperCache.h"
+#include "nsString.h"
+
+namespace mozilla::dom {
+
+class DOMStringList : public nsISupports, public nsWrapperCache {
+ protected:
+  virtual ~DOMStringList();
+
+ public:
+  NS_DECL_CYCLE_COLLECTING_ISUPPORTS
+  NS_DECL_CYCLE_COLLECTION_WRAPPERCACHE_CLASS(DOMStringList)
+
+  virtual JSObject* WrapObject(JSContext* aCx,
+                               JS::Handle<JSObject*> aGivenProto) override;
+  nsISupports* GetParentObject() { return nullptr; }
+
+  void IndexedGetter(uint32_t aIndex, bool& aFound, nsAString& aResult) {
+    EnsureFresh();
+    if (aIndex < mNames.Length()) {
+      aFound = true;
+      aResult = mNames[aIndex];
+    } else {
+      aFound = false;
+    }
+  }
+
+  void Item(uint32_t aIndex, nsAString& aResult) {
+    EnsureFresh();
+    if (aIndex < mNames.Length()) {
+      aResult = mNames[aIndex];
+    } else {
+      aResult.SetIsVoid(true);
+    }
+  }
+
+  uint32_t Length() {
+    EnsureFresh();
+    return mNames.Length();
+  }
+
+  bool Contains(const nsAString& aString) {
+    EnsureFresh();
+    return mNames.Contains(aString);
+  }
+
+  bool Add(const nsAString& aName) {
+    // XXXbz(Bug 1631374) mNames should really be a fallible array; otherwise
+    // this return value is meaningless. return mNames.AppendElement(aName) !=
+    // nullptr;
+    mNames.AppendElement(aName);
+    return true;
+  }
+
+  void Clear() { mNames.Clear(); }
+
+  nsTArray<nsString>& StringArray() { return mNames; }
+
+  void CopyList(nsTArray<nsString>& aNames) { aNames = mNames.Clone(); }
+
+ protected:
+  // A method that subclasses can override to modify mNames as needed
+  // before we index into it or return its length or whatnot.
+  virtual void EnsureFresh() {}
+
+  // XXXbz we really want this to be a fallible array, but we end up passing it
+  // to consumers who declare themselves as taking and nsTArray.  :(
+  nsTArray<nsString> mNames;
+};
+
+}  // namespace mozilla::dom
+
+#endif /* mozilla_dom_DOMStringList_h */