LibJS: Implement Temporal.Duration.prototype.valueOf

Author: https://github.com/trflynn89
Commit: https://github.com/LadybirdBrowser/ladybird/commit/f57ff634328
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/2431
Reviewed-by: https://github.com/alimpfard
Reviewed-by: https://github.com/shannonbooth ✅

Libraries/LibJS/Runtime/Temporal/DurationPrototype.cpp

@@ -46,6 +46,7 @@ void DurationPrototype::initialize(Realm& realm)
     define_native_function(realm, vm.names.toString, to_string, 0, attr);
     define_native_function(realm, vm.names.toJSON, to_json, 0, attr);
     define_native_function(realm, vm.names.toLocaleString, to_locale_string, 0, attr);
+    define_native_function(realm, vm.names.valueOf, value_of, 0, attr);
 }
 
 // 7.3.3 get Temporal.Duration.prototype.years, https://tc39.es/proposal-temporal/#sec-get-temporal.duration.prototype.years
@@ -582,4 +583,11 @@ JS_DEFINE_NATIVE_FUNCTION(DurationPrototype::to_locale_string)
     return PrimitiveString::create(vm, temporal_duration_to_string(duration, Auto {}));
 }
 
+// 7.3.25 Temporal.Duration.prototype.valueOf ( ), https://tc39.es/proposal-temporal/#sec-temporal.duration.prototype.valueof
+JS_DEFINE_NATIVE_FUNCTION(DurationPrototype::value_of)
+{
+    // 1. Throw a TypeError exception.
+    return vm.throw_completion<TypeError>(ErrorType::Convert, "Temporal.Duration", "a primitive value");
+}
+
 }

Libraries/LibJS/Runtime/Temporal/DurationPrototype.h

@@ -40,6 +40,7 @@ private:
     JS_DECLARE_NATIVE_FUNCTION(to_string);
     JS_DECLARE_NATIVE_FUNCTION(to_json);
     JS_DECLARE_NATIVE_FUNCTION(to_locale_string);
+    JS_DECLARE_NATIVE_FUNCTION(value_of);
 };
 
 }

Libraries/LibJS/Tests/builtins/Temporal/Duration/Duration.prototype.valueOf.js

@@ -0,0 +1,7 @@
+describe("errors", () => {
+    test("throws TypeError", () => {
+        expect(() => {
+            new Temporal.Duration().valueOf();
+        }).toThrowWithMessage(TypeError, "Cannot convert Temporal.Duration to a primitive value");
+    });
+});