When attempting to debug a device, we now check whether the web inspector is enabled

src/taco-remote-lib/ios/ios.ts

@@ -266,12 +266,32 @@ class IOSAgent implements ITargetPlatform {
         var portRange: string = util.format("null:%d,:%d-%d", this.webDebugProxyDevicePort, this.webDebugProxyPortMin, this.webDebugProxyPortMax);
 
         var deferred = Q.defer();
-        sharedState.webProxyInstance = child_process.spawn("ios_webkit_debug_proxy", ["-c", portRange]);
+	// Since we want to read the (very sparse) output interactively,
+	// we must make sure to the output of ios_webkit_debug_proxy is not buffered.
+	// The OSX command "script" provides one way to do that
+        sharedState.webProxyInstance = child_process.spawn("script", ["-q", "/dev/null", "ios_webkit_debug_proxy", "-c", portRange], { stdio: "pipe" });
         sharedState.webProxyInstance.on("error", function (err: Error) {
             deferred.reject(new Error(resources.getStringForLanguage(req, "UnableToDebug")));
         });
-        // Allow some time for the spawned process to error out
-        Q.delay(250).then(() => deferred.resolve({}));
+
+        if (buildInfo.options.indexOf("--device" !== -1)) {
+            // This is enabling debugging for a device build: make sure that a device is attached
+	    sharedState.webProxyInstance.stdout.on("data", function (data: Buffer) {
+		var dataStr = data.toString();
+                if (dataStr.match(/Unable to connect to/)) {
+		    var error = new Error(resources.getStringForLanguage(req, "WebInspectorDisabled"));
+		    deferred.reject(error);
+		}
+		if (dataStr.match(/Connected :[0-9]+ to/)) {
+		    deferred.resolve();
+		}
+            });
+	    // Allow time to discover devices to register.
+	    Q.delay(10000).then(() => deferred.reject(new Error(resources.getStringForLanguage(req, "NoDevicesFound"))));
+        } else {
+            // Allow some time for the spawned process to error out
+            Q.delay(250).then(() => deferred.resolve({}));
+        }
 
         deferred.promise.then(() => {
             buildInfo["webDebugProxyPort"] = this.webDebugProxyDevicePort;

src/taco-remote-lib/resources/en/resources.json

@@ -37,6 +37,10 @@
     "_RunSuccess.comment": "Message sent back to Visual Studio when it requests the build server to run a build and the attempt is successful (the application is running on the device)",
     "DebugSuccess": "Successfully Debugging on the device",
     "_DebugSuccess.comment": "Message sent back to Visual Studio when it requests the build server to debug a build and the attempt is successful (the debugger is running)",
+    "WebInspectorDisabled": "The web inspector is not enabled on the device. Please enable it in Settings -> Safari -> Advanced -> Web Inspector",
+    "_WebInspectorDisabled.comment": "Message sent back to the client when they request debugging for a device build but the device is not configured for debugging. The Settings -> Safari etc corresponds to a menu on the physical device.",
+    "NoDevicesFound": "No devices found to debug. Please ensure that a device is connected and awake and retry.",
+    "_NoDevicesFound.comment": "Message sent back to the client when they request debugging for a device build but no devices are discovered.",
     "ProvisioningFailed": "Installation failed: Check your provisioning profile",
     "_ProvisioningFailed.comment": "Message sent back to Visual Studio or user when it attempts to install an app on a device without an appropriate provisioning profile",
     "IOSSimNotFound": "****** ios-sim is not installed on path. `sudo npm install -g ios-sim` if you want this server to support emulator.",