LibJS: Implement Temporal.ZonedDateTime.prototype.withCalendar

Userland/Libraries/LibJS/Tests/builtins/Temporal/ZonedDateTime/ZonedDateTime.prototype.withCalendar.js

@@ -0,0 +1,43 @@
+describe("correct behavior", () => {
+    test("length is 1", () => {
+        expect(Temporal.ZonedDateTime.prototype.withCalendar).toHaveLength(1);
+    });
+
+    test("basic functionality", () => {
+        const object = {};
+        const zonedDateTime = new Temporal.ZonedDateTime(1n, {}, object);
+        expect(zonedDateTime.calendar).toBe(object);
+
+        const calendar = new Temporal.Calendar("iso8601");
+        const withCalendarZonedDateTime = zonedDateTime.withCalendar(calendar);
+        expect(withCalendarZonedDateTime.calendar).toBe(calendar);
+    });
+
+    test("from calendar string", () => {
+        const object = {};
+        const zonedDateTime = new Temporal.ZonedDateTime(1n, {}, object);
+        expect(zonedDateTime.calendar).toBe(object);
+
+        const withCalendarZonedDateTime = zonedDateTime.withCalendar("iso8601");
+        expect(withCalendarZonedDateTime.calendar).toBeInstanceOf(Temporal.Calendar);
+        expect(withCalendarZonedDateTime.calendar.id).toBe("iso8601");
+    });
+});
+
+describe("errors", () => {
+    test("this value must be a Temporal.ZonedDateTime object", () => {
+        expect(() => {
+            Temporal.ZonedDateTime.prototype.withCalendar.call("foo");
+        }).toThrowWithMessage(TypeError, "Not an object of type Temporal.ZonedDateTime");
+    });
+
+    // FIXME: Enable this when calendar string parsing is implemented.
+    test.skip("from invalid calendar string", () => {
+        const zonedDateTime = new Temporal.ZonedDateTime(1n, {}, {});
+
+        // FIXME: Use "toThrowWithMessage" once this has an error message.
+        expect(() => {
+            zonedDateTime.withCalendar("iso8602foobar");
+        }).toThrow(RangeError);
+    });
+});