Adds invalid constuction options

test/built-ins/Temporal/PlainYearMonth/prototype/since/options-invalid.js

@@ -0,0 +1,22 @@
+// 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.plainyearmonth.prototype.since
+description: Verify that invalid options are handled correctly.
+features: [Temporal]
+---*/
+
+const feb20 = new Temporal.PlainYearMonth(2020, 2);
+const feb21 = new Temporal.PlainYearMonth(2021, 2);
+
+[
+  null,
+  1,
+  'hello',
+  true,
+  Symbol('foo'),
+  1n
+].forEach((badOption) =>
+  assert.throws(TypeError, () => feb21.since(feb20, badOption), `${String(badOption)} throws TypeError`)
+);