Quickly testing iOS and objective-c code

Question

I was wondering if is there any way to quickly check iOS/objective-c snippets or new code inside my xcode project without having to compile the whole app for that, open up the simulator just to get the NSLog message traced on the console.

I remember when life was easier using ruby's irb or node command for node.js :)

It just gives me the impression that on iOS development you have to learn how to deal with this high complexity and dependencies all the time, but I am just starting on this new world. so any help would be appreciated.

thanks a lot

Answer 1

This timely blog post should help; I'm using it often already.

Update : there is also Code Runner available in Mac App Store - this supports many languages, including Objective-C.

Answer 2

An Xcode project can contain multiple targets. One of the targets can be a test driver in which you can put some class/object/snippet exercise code and drive it from the command-line, results to the debug console. Another option is to create unit test targets.

Answer 3

If the code you're writing has known expected input-output pairs and you're just writing code to make them work, you may want to look into using XCode's unit testing capabilities. A link to a tutorial on using unit tests is at http://developer.apple.com/library/mac/#documentation/DeveloperTools/Conceptual/UnitTesting/0-Introduction/introduction.html . If you want to test more interactive things, it is possible to use Instruments (a program in XCode) to automate those tests as well using the Automation instrument. A guide on using Instruments is available at http://developer.apple.com/library/mac/#documentation/DeveloperTools/Conceptual/InstrumentsUserGuide/AboutTracing/AboutTracing.html .

Answer 4

Not really—Objective-C is a compiled language, while I believe Ruby is interpreted (which allows for interactive testing like what you describe). You can reduce some of the overhead of building and running your project by just leaving the simulator open; stopping the app from Xcode will close the app but leave the simulator running, meaning that a rebuilt version of the app will launch more quickly when you run it.