1 files changed, 20 insertions, 0 deletions
diff --git a/Userland/Libraries/LibJS/Runtime/Intl/PluralRulesConstructor.cpp b/Userland/Libraries/LibJS/Runtime/Intl/PluralRulesConstructor.cpp
index 95ba0d416e..fa95275c09 100644
--- a/Userland/Libraries/LibJS/Runtime/Intl/PluralRulesConstructor.cpp
+++ b/Userland/Libraries/LibJS/Runtime/Intl/PluralRulesConstructor.cpp
@@ -5,7 +5,9 @@
  */
 
 #include <LibJS/Runtime/AbstractOperations.h>
+#include <LibJS/Runtime/Array.h>
 #include <LibJS/Runtime/GlobalObject.h>
+#include <LibJS/Runtime/Intl/AbstractOperations.h>
 #include <LibJS/Runtime/Intl/PluralRules.h>
 #include <LibJS/Runtime/Intl/PluralRulesConstructor.h>
 
@@ -26,6 +28,9 @@ void PluralRulesConstructor::initialize(GlobalObject& global_object)
     // 16.3.1 Intl.PluralRules.prototype, https://tc39.es/ecma402/#sec-intl.pluralrules.prototype
     define_direct_property(vm.names.prototype, global_object.intl_plural_rules_prototype(), 0);
     define_direct_property(vm.names.length, Value(0), Attribute::Configurable);
+
+    u8 attr = Attribute::Writable | Attribute::Configurable;
+    define_native_function(vm.names.supportedLocalesOf, supported_locales_of, 1, attr);
 }
 
 // 16.2.1 Intl.PluralRules ( [ locales [ , options ] ] ), https://tc39.es/ecma402/#sec-intl.pluralrules
@@ -51,4 +56,19 @@ ThrowCompletionOr<Object*> PluralRulesConstructor::construct(FunctionObject& new
     return TRY(initialize_plural_rules(global_object, *plural_rules, locales, options));
 }
 
+// 16.3.2 Intl.PluralRules.supportedLocalesOf ( locales [ , options ] ), https://tc39.es/ecma402/#sec-intl.pluralrules.supportedlocalesof
+JS_DEFINE_NATIVE_FUNCTION(PluralRulesConstructor::supported_locales_of)
+{
+    auto locales = vm.argument(0);
+    auto options = vm.argument(1);
+
+    // 1. Let availableLocales be %PluralRules%.[[AvailableLocales]].
+
+    // 2. Let requestedLocales be ? CanonicalizeLocaleList(locales).
+    auto requested_locales = TRY(canonicalize_locale_list(global_object, locales));
+
+    // 3. Return ? SupportedLocales(availableLocales, requestedLocales, options).
+    return TRY(supported_locales(global_object, requested_locales, options));
+}
+
 }