LibJS: Implement Temporal.PlainYearMonth.prototype.getISOFields()

Userland/Libraries/LibJS/Runtime/Temporal/PlainYearMonthPrototype.cpp

@@ -38,6 +38,7 @@ void PlainYearMonthPrototype::initialize(GlobalObject& global_object)
 
     u8 attr = Attribute::Writable | Attribute::Configurable;
     define_native_function(vm.names.valueOf, value_of, 0, attr);
+    define_native_function(vm.names.getISOFields, get_iso_fields, 0, attr);
 }
 
 static PlainYearMonth* typed_this(GlobalObject& global_object)
@@ -186,4 +187,32 @@ JS_DEFINE_NATIVE_FUNCTION(PlainYearMonthPrototype::value_of)
     return {};
 }
 
+// 9.3.22 Temporal.PlainYearMonth.prototype.getISOFields ( ), https://tc39.es/proposal-temporal/#sec-temporal.plainyearmonth.prototype.getisofields
+JS_DEFINE_NATIVE_FUNCTION(PlainYearMonthPrototype::get_iso_fields)
+{
+    // 1. Let yearMonth be the this value.
+    // 2. Perform ? RequireInternalSlot(yearMonth, [[InitializedTemporalYearMonth]]).
+    auto* year_month = typed_this(global_object);
+    if (vm.exception())
+        return {};
+
+    // 3. Let fields be ! OrdinaryObjectCreate(%Object.prototype%).
+    auto* fields = Object::create(global_object, global_object.object_prototype());
+
+    // 4. Perform ! CreateDataPropertyOrThrow(fields, "calendar", yearMonth.[[Calendar]]).
+    fields->create_data_property_or_throw(vm.names.calendar, Value(&year_month->calendar()));
+
+    // 5. Perform ! CreateDataPropertyOrThrow(fields, "isoDay", 𝔽(yearMonth.[[ISODay]])).
+    fields->create_data_property_or_throw(vm.names.isoDay, Value(year_month->iso_day()));
+
+    // 6. Perform ! CreateDataPropertyOrThrow(fields, "isoMonth", 𝔽(yearMonth.[[ISOMonth]])).
+    fields->create_data_property_or_throw(vm.names.isoMonth, Value(year_month->iso_month()));
+
+    // 7. Perform ! CreateDataPropertyOrThrow(fields, "isoYear", 𝔽(yearMonth.[[ISOYear]])).
+    fields->create_data_property_or_throw(vm.names.isoYear, Value(year_month->iso_year()));
+
+    // 8. Return fields.
+    return fields;
+}
+
 }

Userland/Libraries/LibJS/Runtime/Temporal/PlainYearMonthPrototype.h

@@ -28,6 +28,7 @@ private:
     JS_DECLARE_NATIVE_FUNCTION(months_in_year_getter);
     JS_DECLARE_NATIVE_FUNCTION(in_leap_year_getter);
     JS_DECLARE_NATIVE_FUNCTION(value_of);
+    JS_DECLARE_NATIVE_FUNCTION(get_iso_fields);
 };
 
 }

Userland/Libraries/LibJS/Tests/builtins/Temporal/PlainYearMonth/PlainYearMonth.prototype.getISOFields.js

@@ -0,0 +1,27 @@
+describe("normal behavior", () => {
+    test("length is 0", () => {
+        expect(Temporal.PlainYearMonth.prototype.getISOFields).toHaveLength(0);
+    });
+
+    test("basic functionality", () => {
+        const calendar = new Temporal.Calendar("iso8601");
+        const plainYearMonth = new Temporal.PlainYearMonth(2021, 7, calendar, 6);
+        const fields = plainYearMonth.getISOFields();
+        expect(fields).toEqual({ calendar, isoDay: 6, isoMonth: 7, isoYear: 2021 });
+        // Test field order
+        expect(Object.getOwnPropertyNames(fields)).toEqual([
+            "calendar",
+            "isoDay",
+            "isoMonth",
+            "isoYear",
+        ]);
+    });
+});
+
+describe("errors", () => {
+    test("this value must be a Temporal.PlainYearMonth object", () => {
+        expect(() => {
+            Temporal.PlainYearMonth.prototype.getISOFields.call("foo");
+        }).toThrowWithMessage(TypeError, "Not a Temporal.PlainYearMonth");
+    });
+});