1 files changed, 69 insertions, 0 deletions
diff --git a/js/src/tests/test262/intl402/Locale/extensions-grandfathered.js b/js/src/tests/test262/intl402/Locale/extensions-grandfathered.js
new file mode 100644
index 0000000000..af4f9e0abc
--- /dev/null
+++ b/js/src/tests/test262/intl402/Locale/extensions-grandfathered.js
@@ -0,0 +1,69 @@
+// Copyright 2018 André Bargull; Igalia, S.L. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+esid: sec-intl.locale
+description: >
+    Verifies handling of options with grandfathered tags.
+info: |
+    ApplyOptionsToTag( tag, options )
+    ...
+    2. If IsStructurallyValidLanguageTag(tag) is false, throw a RangeError exception.
+
+    IsStructurallyValidLanguageTag ( locale )
+
+    The IsStructurallyValidLanguageTag abstract operation verifies that the
+    locale argument (which must be a String value)
+
+    represents a well-formed Unicode BCP 47 Locale Identifier" as specified in
+    Unicode Technical Standard 35 section 3.2, or successor,
+
+features: [Intl.Locale]
+---*/
+
+const testData = [
+    // Regular grandfathered without modern replacement.
+    {
+        tag: "cel-gaulish",
+        options: {
+            language: "fr",
+            script: "Cyrl",
+            region: "FR",
+            numberingSystem: "latn",
+        },
+        canonical: "fr-Cyrl-FR-u-nu-latn",
+    },
+
+    // Regular grandfathered with modern replacement.
+    {
+        tag: "art-lojban",
+        options: {
+            language: "fr",
+            script: "Cyrl",
+            region: "ZZ",
+            numberingSystem: "latn",
+        },
+        canonical: "fr-Cyrl-ZZ-u-nu-latn",
+    },
+];
+
+for (const {tag, options, canonical} of testData) {
+    const loc = new Intl.Locale(tag, options);
+    assert.sameValue(loc.toString(), canonical);
+
+    for (const [name, value] of Object.entries(options)) {
+        assert.sameValue(loc[name], value);
+    }
+}
+
+assert.throws(RangeError, () =>
+    new Intl.Locale("i-default",
+      {language: "fr", script: "Cyrl", region: "DE", numberingSystem: "latn"}
+      ));
+
+assert.throws(RangeError, () =>
+    new Intl.Locale("en-gb-oed",
+      {language: "fr", script: "Cyrl", region: "US", numberingSystem: "latn"}
+      ));
+
+reportCompare(0, 0);