1 files changed, 87 insertions, 0 deletions
diff --git a/js/src/builtin/intl/RelativeTimeFormat.h b/js/src/builtin/intl/RelativeTimeFormat.h
new file mode 100644
index 0000000000..f46aaa217b
--- /dev/null
+++ b/js/src/builtin/intl/RelativeTimeFormat.h
@@ -0,0 +1,87 @@
+/* -*- 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 builtin_intl_RelativeTimeFormat_h
+#define builtin_intl_RelativeTimeFormat_h
+
+#include "mozilla/intl/NumberPart.h"
+
+#include <stdint.h>
+
+#include "builtin/SelfHostingDefines.h"
+#include "gc/Barrier.h"
+#include "js/Class.h"
+#include "vm/NativeObject.h"
+
+namespace mozilla::intl {
+class RelativeTimeFormat;
+}
+
+namespace js {
+
+class RelativeTimeFormatObject : public NativeObject {
+ public:
+  static const JSClass class_;
+  static const JSClass& protoClass_;
+
+  static constexpr uint32_t INTERNALS_SLOT = 0;
+  static constexpr uint32_t URELATIVE_TIME_FORMAT_SLOT = 1;
+  static constexpr uint32_t SLOT_COUNT = 2;
+
+  static_assert(INTERNALS_SLOT == INTL_INTERNALS_OBJECT_SLOT,
+                "INTERNALS_SLOT must match self-hosting define for internals "
+                "object slot");
+
+  // Estimated memory use for URelativeDateTimeFormatter (see IcuMemoryUsage).
+  static constexpr size_t EstimatedMemoryUse = 10896;
+
+  mozilla::intl::RelativeTimeFormat* getRelativeTimeFormatter() const {
+    const auto& slot = getFixedSlot(URELATIVE_TIME_FORMAT_SLOT);
+    if (slot.isUndefined()) {
+      return nullptr;
+    }
+    return static_cast<mozilla::intl::RelativeTimeFormat*>(slot.toPrivate());
+  }
+
+  void setRelativeTimeFormatter(mozilla::intl::RelativeTimeFormat* rtf) {
+    setFixedSlot(URELATIVE_TIME_FORMAT_SLOT, PrivateValue(rtf));
+  }
+
+ private:
+  static const JSClassOps classOps_;
+  static const ClassSpec classSpec_;
+
+  static void finalize(JS::GCContext* gcx, JSObject* obj);
+};
+
+/**
+ * Returns a relative time as a string formatted according to the effective
+ * locale and the formatting options of the given RelativeTimeFormat.
+ *
+ * |t| should be a number representing a number to be formatted.
+ * |unit| should be "second", "minute", "hour", "day", "week", "month",
+ *                  "quarter", or "year".
+ * |numeric| should be "always" or "auto".
+ *
+ * Usage: formatted = intl_FormatRelativeTime(relativeTimeFormat, t,
+ *                                            unit, numeric, formatToParts)
+ */
+[[nodiscard]] extern bool intl_FormatRelativeTime(JSContext* cx, unsigned argc,
+                                                  JS::Value* vp);
+
+namespace intl {
+
+using FieldType = js::ImmutableTenuredPtr<PropertyName*> JSAtomState::*;
+
+[[nodiscard]] bool FormattedRelativeTimeToParts(
+    JSContext* cx, HandleString str,
+    const mozilla::intl::NumberPartVector& parts, FieldType relativeTimeUnit,
+    MutableHandleValue result);
+
+}  // namespace intl
+}  // namespace js
+
+#endif /* builtin_intl_RelativeTimeFormat_h */