LibJS: Implement Temporal.PlainTime.prototype.valueOf

Author: https://github.com/trflynn89
Commit: https://github.com/LadybirdBrowser/ladybird/commit/e37c9eaeff3
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/2535

Libraries/LibJS/Runtime/Temporal/PlainTimePrototype.cpp

@@ -46,6 +46,7 @@ void PlainTimePrototype::initialize(Realm& realm)
     define_native_function(realm, vm.names.toString, to_string, 0, attr);
     define_native_function(realm, vm.names.toLocaleString, to_locale_string, 0, attr);
     define_native_function(realm, vm.names.toJSON, to_json, 0, attr);
+    define_native_function(realm, vm.names.valueOf, value_of, 0, attr);
 }
 
 // 4.3.3 get Temporal.PlainTime.prototype.hour, https://tc39.es/proposal-temporal/#sec-get-temporal.plaintime.prototype.hour
@@ -336,4 +337,11 @@ JS_DEFINE_NATIVE_FUNCTION(PlainTimePrototype::to_json)
     return PrimitiveString::create(vm, time_record_to_string(temporal_time->time(), Auto {}));
 }
 
+// 4.3.19 Temporal.PlainTime.prototype.valueOf ( ), https://tc39.es/proposal-temporal/#sec-temporal.plaintime.prototype.valueof
+JS_DEFINE_NATIVE_FUNCTION(PlainTimePrototype::value_of)
+{
+    // 1. Throw a TypeError exception.
+    return vm.throw_completion<TypeError>(ErrorType::Convert, "Temporal.PlainTime", "a primitive value");
+}
+
 }

Libraries/LibJS/Runtime/Temporal/PlainTimePrototype.h

@@ -39,6 +39,7 @@ private:
     JS_DECLARE_NATIVE_FUNCTION(to_string);
     JS_DECLARE_NATIVE_FUNCTION(to_locale_string);
     JS_DECLARE_NATIVE_FUNCTION(to_json);
+    JS_DECLARE_NATIVE_FUNCTION(value_of);
 };
 
 }

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

@@ -0,0 +1,7 @@
+describe("errors", () => {
+    test("throws TypeError", () => {
+        expect(() => {
+            new Temporal.PlainTime(19, 54, 38).valueOf();
+        }).toThrowWithMessage(TypeError, "Cannot convert Temporal.PlainTime to a primitive value");
+    });
+});