1 files changed, 39 insertions, 0 deletions
diff --git a/js/src/tests/test262/intl402/Locale/constructor-tag-tostring.js b/js/src/tests/test262/intl402/Locale/constructor-tag-tostring.js
new file mode 100644
index 0000000000..21472ca467
--- /dev/null
+++ b/js/src/tests/test262/intl402/Locale/constructor-tag-tostring.js
@@ -0,0 +1,39 @@
+// Copyright 2018 Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-intl.locale
+description: >
+    Checks error cases for the string conversion of the locale argument to the
+    Locale constructor.
+info: |
+    Intl.Locale( tag [, options] )
+
+    ...
+    8. If Type(tag) is Object and tag has an [[InitializedLocale]] internal slot, then
+    9. Else,
+        a. Let tag be ? ToString(tag).
+features: [Intl.Locale]
+---*/
+
+function CustomError() {}
+function WrongCustomError() {}
+
+const errors = [
+  { get [Symbol.toPrimitive]() { throw new CustomError(); } },
+  { [Symbol.toPrimitive](hint) { assert.sameValue(hint, "string"); throw new CustomError(); } },
+  { get toString() { throw new CustomError(); }, get valueOf() { throw new WrongCustomError(); } },
+  { toString() { throw new CustomError(); }, get valueOf() { throw new WrongCustomError(); } },
+  { toString: undefined, get valueOf() { throw new CustomError(); } },
+  { toString: undefined, valueOf() { throw new CustomError(); } },
+  { toString() { return {} }, get valueOf() { throw new CustomError(); } },
+  { toString() { return {} }, valueOf() { throw new CustomError(); } },
+];
+
+for (const input of errors) {
+  assert.throws(CustomError, function() {
+    new Intl.Locale(input);
+  });
+}
+
+reportCompare(0, 0);