Add tests for PlainDate.from() with the Gregorian calendar.

polyfill/test/all.mjs

@@ -26,7 +26,6 @@ import './plaindatetime.mjs';
 import './duration.mjs';
 import './plainyearmonth.mjs';
 import './intl.mjs';
-import './calendar.mjs';
 
 // tests of userland objects
 import './usertimezone.mjs';

polyfill/test/intl402/Temporal/PlainDate/constructor/from/basic.js

@@ -0,0 +1,29 @@
+// 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.from
+description: Basic tests for PlainDate.from() with the Gregorian calendar.
+includes: [compareArray.js, temporalHelpers.js]
+features: [Temporal]
+---*/
+
+TemporalHelpers.assertPlainDate(
+  Temporal.PlainDate.from("1999-12-31[u-ca=gregory]"),
+  1999, 12, "M12", 31, "string era CE", "ce", 1999);
+
+TemporalHelpers.assertPlainDate(
+  Temporal.PlainDate.from("-000001-12-31[u-ca=gregory]"),
+  -1, 12, "M12", 31, "string era BCE", "bce", 2);
+
+TemporalHelpers.assertPlainDate(
+  Temporal.PlainDate.from({ era: "ce", eraYear: 1999, month: 12, day: 31, calendar: "gregory" }),
+  1999, 12, "M12", 31, "property bag explicit era CE", "ce", 1999);
+
+TemporalHelpers.assertPlainDate(
+  Temporal.PlainDate.from({ year: 1999, month: 12, day: 31, calendar: "gregory" }),
+  1999, 12, "M12", 31, "property bag implicit era CE", "ce", 1999);
+
+TemporalHelpers.assertPlainDate(
+  Temporal.PlainDate.from({ era: "bce", eraYear: 2, month: 12, day: 31, calendar: "gregory" }),
+  -1, 12, "M12", 31, "property bag era BCE", "bce", 2);