1 files changed, 48 insertions, 0 deletions
diff --git a/js/src/tests/test262/built-ins/Temporal/PlainDate/prototype/toString/options-undefined.js b/js/src/tests/test262/built-ins/Temporal/PlainDate/prototype/toString/options-undefined.js
new file mode 100644
index 0000000000..5b44173c28
--- /dev/null
+++ b/js/src/tests/test262/built-ins/Temporal/PlainDate/prototype/toString/options-undefined.js
@@ -0,0 +1,48 @@
+// |reftest| skip-if(!this.hasOwnProperty('Temporal')) -- Temporal is not enabled unconditionally
+// Copyright (C) 2021 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-temporal.plaindate.prototype.tostring
+description: Verify that undefined options are handled correctly.
+features: [Temporal]
+---*/
+
+const calendar = {
+  dateAdd() {},
+  dateFromFields() {},
+  dateUntil() {},
+  day() {},
+  dayOfWeek() {},
+  dayOfYear() {},
+  daysInMonth() {},
+  daysInWeek() {},
+  daysInYear() {},
+  fields() {},
+  id: "custom",
+  inLeapYear() {},
+  mergeFields() {},
+  month() {},
+  monthCode() {},
+  monthDayFromFields() {},
+  monthsInYear() {},
+  weekOfYear() {},
+  year() {},
+  yearMonthFromFields() {},
+  yearOfWeek() {},
+};
+const date1 = new Temporal.PlainDate(2000, 5, 2);
+const date2 = new Temporal.PlainDate(2000, 5, 2, calendar);
+
+[
+  [date1, "2000-05-02"],
+  [date2, "2000-05-02[u-ca=custom]"],
+].forEach(([date, expected]) => {
+  const explicit = date.toString(undefined);
+  assert.sameValue(explicit, expected, "default calendarName option is auto");
+
+  const implicit = date.toString();
+  assert.sameValue(implicit, expected, "default calendarName option is auto");
+});
+
+reportCompare(0, 0);