1 files changed, 35 insertions, 0 deletions
diff --git a/js/src/tests/non262/Intl/available-locales-implied-script.js b/js/src/tests/non262/Intl/available-locales-implied-script.js
new file mode 100644
index 0000000000..d9abbebf49
--- /dev/null
+++ b/js/src/tests/non262/Intl/available-locales-implied-script.js
@@ -0,0 +1,35 @@
+// |reftest| skip-if(!this.hasOwnProperty('Intl'))
+
+if (typeof getAvailableLocalesOf === "undefined") {
+  var getAvailableLocalesOf = SpecialPowers.Cu.getJSTestingFunctions().getAvailableLocalesOf;
+}
+
+function IsIntlService(c) {
+  return typeof c === "function" &&
+         c.hasOwnProperty("prototype") &&
+         c.prototype.hasOwnProperty("resolvedOptions");
+}
+
+const intlConstructors = Object.getOwnPropertyNames(Intl).map(name => Intl[name]).filter(IsIntlService);
+
+// Test all Intl service constructors.
+for (let intlConstructor of intlConstructors) {
+  // Retrieve all available locales of the given Intl service constructor.
+  let available = getAvailableLocalesOf(intlConstructor.name);
+  let availableSet = new Set(available);
+
+  available.filter(x => {
+    return new Intl.Locale(x);
+  }).filter(loc => {
+    // Find all locales which have both a script and a region subtag.
+    return loc.script && loc.region;
+  }).forEach(loc => {
+    let noScript = `${loc.language}-${loc.region}`;
+
+    // The locale without a script subtag must also be available.
+    assertEq(availableSet.has(noScript), true, `Missing locale ${noScript} for ${loc}`);
+  });
+}
+
+if (typeof reportCompare === "function")
+  reportCompare(true, true);