diff -r 000000000000 -r 6474c204b198 dom/telephony/test/marionette/test_dsds_default_service_id.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/dom/telephony/test/marionette/test_dsds_default_service_id.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,127 @@
+/* Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/ */
+
+MARIONETTE_TIMEOUT = 60000;
+MARIONETTE_CONTEXT = "chrome";
+
+Cu.import("resource://gre/modules/Promise.jsm");
+
+const TELEPHONY_PROVIDER_CONTRACTID =
+  "@mozilla.org/telephony/telephonyprovider;1";
+
+const PREF_RIL_NUM_RADIO_INTERFACES = "ril.numRadioInterfaces";
+const PREF_DEFAULT_SERVICE_ID = "dom.telephony.defaultServiceId";
+
+function setPrefAndVerify(prefKey, setVal, service, attrName, expectedVal, deferred) {
+  log("  Set '" + prefKey + "' to " + setVal);
+  Services.prefs.setIntPref(prefKey, setVal);
+  let prefVal = Services.prefs.getIntPref(prefKey);
+  is(prefVal, setVal, "'" + prefKey + "' set to " + setVal);
+
+  window.setTimeout(function() {
+    let defaultVal = service[attrName];
+    is(defaultVal, expectedVal, attrName);
+
+    deferred.resolve(service);
+  }, 0);
+}
+
+function getNumRadioInterfaces() {
+  let deferred = Promise.defer();
+
+  window.setTimeout(function() {
+    let numRil = Services.prefs.getIntPref(PREF_RIL_NUM_RADIO_INTERFACES);
+    log("numRil = " + numRil);
+
+    deferred.resolve(numRil);
+  }, 0);
+
+  return deferred.promise;
+}
+
+function getService(contractId, ifaceName) {
+  let deferred = Promise.defer();
+
+  window.setTimeout(function() {
+    log("Getting service for " + ifaceName);
+    let service = Cc[contractId].getService(Ci[ifaceName]);
+    ok(service, "service.constructor is " + service.constructor);
+
+    deferred.resolve(service);
+  }, 0);
+
+  return deferred.promise;
+}
+
+function checkInitialEquality(attrName, prefKey, service) {
+  let deferred = Promise.defer();
+
+  log("  Checking initial value for '" + prefKey + "'");
+  let origPrefVal = Services.prefs.getIntPref(prefKey);
+  ok(isFinite(origPrefVal), "default '" + prefKey + "' value");
+
+  window.setTimeout(function() {
+    let defaultVal = service[attrName];
+    is(defaultVal, origPrefVal, attrName);
+
+    deferred.resolve(service);
+  }, 0);
+
+  return deferred.promise;
+}
+
+function checkSetToNegtiveValue(attrName, prefKey, service) {
+  let deferred = Promise.defer();
+
+  // Set to -1 and verify defaultVal == 0.
+  setPrefAndVerify(prefKey, -1, service, attrName, 0, deferred);
+
+  return deferred.promise;
+}
+
+function checkSetToOverflowedValue(attrName, prefKey, numRil, service) {
+  let deferred = Promise.defer();
+
+  // Set to larger-equal than numRil and verify defaultVal == 0.
+  setPrefAndVerify(prefKey, numRil, service, attrName, 0, deferred);
+
+  return deferred.promise;
+}
+
+function checkValueChange(attrName, prefKey, numRil, service) {
+  let deferred = Promise.defer();
+
+  if (numRil > 1) {
+    // Set to (numRil - 1) and verify defaultVal equals.
+    setPrefAndVerify(prefKey, numRil - 1, service, attrName, numRil - 1, deferred);
+  } else {
+    window.setTimeout(function() {
+      deferred.resolve(service);
+    }, 0);
+  }
+
+  return deferred.promise;
+}
+
+function verify(contractId, ifaceName, attrName, prefKey, numRil) {
+  let deferred = Promise.defer();
+
+  getService(contractId, ifaceName)
+    .then(checkInitialEquality.bind(null, attrName, prefKey))
+    .then(checkSetToNegtiveValue.bind(null, attrName, prefKey))
+    .then(checkSetToOverflowedValue.bind(null, attrName, prefKey, numRil))
+    .then(checkValueChange.bind(null, attrName, prefKey, numRil))
+    .then(function() {
+      // Reset.
+      Services.prefs.clearUserPref(prefKey);
+
+      deferred.resolve(numRil);
+    });
+
+  return deferred.promise;
+}
+
+getNumRadioInterfaces()
+  .then(verify.bind(null, TELEPHONY_PROVIDER_CONTRACTID, "nsITelephonyProvider",
+                    "defaultServiceId", PREF_DEFAULT_SERVICE_ID))
+  .then(finish);