check we can launch a device based on user's caps and throw a nice er…

…ror if not (fix #2114)

lib/devices/ios/ios.js

@@ -266,6 +266,7 @@ IOS.prototype.start = function (cb, onDie) {
     this.setLocale.bind(this),
     this.setPreferences.bind(this),
     this.startLogCapture.bind(this),
+    this.createInstruments.bind(this),
     this.setDeviceAndLaunchSimulator.bind(this),
     this.installToRealDevice.bind(this),
     this.startInstruments.bind(this),
@@ -278,9 +279,14 @@ IOS.prototype.start = function (cb, onDie) {
   });
 };
 
-IOS.prototype.startInstruments = function (cb) {
+IOS.prototype.createInstruments = function (cb) {
   logger.debug("Creating instruments");
   this.instruments = this.makeInstruments();
+  cb();
+};
+
+IOS.prototype.startInstruments = function (cb) {
+  logger.debug("Starting instruments");
   this.instruments.start(function (err) {
     if (err) {
       if (!_.isEmpty(this.logs)) {
@@ -875,6 +881,22 @@ IOS.prototype.setDeviceAndLaunchSimulator = function (cb) {
         this.setDeviceTypeInInfoPlist(isiPhone ? 1 : 2, cb);
       }.bind(this);
 
+      var checkDeviceAvailable = function (cb) {
+        logger.debug("Checking whether instruments supports our device string");
+        this.instruments.getAvailableDevices(function (err, availDevices) {
+          var dString = this.getDeviceString();
+          if (err) return cb(err);
+          if (!_.contains(availDevices, dString)) {
+            var msg = "Could not find a device to launch. You requested '" +
+                      dString + "', but the available devices were: " +
+                      JSON.stringify(availDevices);
+            logger.error(msg);
+            return cb(new Error(msg));
+          }
+          cb();
+        }.bind(this));
+      }.bind(this);
+
       var startSim = function (cb) {
         logger.debug("Launching device: " + this.getDeviceString());
         var iosSimArgs = ["-SimulateDevice", this.getDeviceString()];
@@ -905,6 +927,7 @@ IOS.prototype.setDeviceAndLaunchSimulator = function (cb) {
       } else {
         async.series([
           this.endSimulator.bind(this),
+          checkDeviceAvailable,
           cleanup,
         ], function (err) {
           cb(err);

package.json

@@ -79,7 +79,7 @@
     "date-utils": "~1.2.14",
     "bytes": "~0.2.1",
     "appium-atoms": "~0.0.5",
-    "appium-instruments": "~0.1.19",
+    "appium-instruments": "~0.1.20",
     "appium-uiauto": "~0.0.15",
     "mv": "~2.0.0",
     "js2xmlparser2": "~0.2.0",

test/functional/ios/testapp/device-specs.js

@@ -1,6 +1,9 @@
+/*globals should:true */
 "use strict";
 
 var setup = require("../../common/setup-base"),
+    _ = require('underscore'),
+    initSession = require('../../../helpers/session').initSession,
     desired = require('./desired');
 
 describe('testapp - device -', function () {
@@ -25,4 +28,15 @@ describe('testapp - device -', function () {
     });
   });
 
+  describe('deviceName', function () {
+    var newDesired = _.extend(_.clone(desired), {deviceName: "iFailure 3.5-inch"});
+    var session = initSession(newDesired, {'no-retry': true});
+
+    it('should fail gracefully with an invalid deviceName', function (done) {
+      session.setUp()
+        .should.be.rejectedWith(/environment you requested was unavailable/)
+        .nodeify(done);
+    });
+  });
+
 });