Three New Xcode 8 Testing Features

I’m in the middle of watching the Platforms State of the Union from WWDC 2016, and there were three new Xcode 8 testing features announced for Xcode 8 that are so exciting for me. They are all related to automated testing. Did you catch them? They were:

  1. Test crash logs are captured.
  2. xcodebuild can now run with pre-built tests.
  3. Indexing tests is now 50x faster.

Capturing Crash Logs

Have you ever ran a test, unit or UI, that triggered an app crash? It just happened to me today. I bug when animating a UIPresentationController surfaced on iOS8. Unfortunately, Xcode 7 doesn’t capture crash logs when a test triggers a crash. Instead, you have to go back, re-run the test several times, set some breakpoints, and hone in on the code that caused the crash. Luckily, this is changing in Xcode 8 as crash logs will automatically be captured when a test crashes. This means you’ll instantly know the offending line of code that caused the crash, and will be able to fix it that much faster, and move on to building other pieces of your app.

Running with Pre-Built Tests

There’s no way in Xcode 7 to provide a pre-built bundle of compiled tests to be executed against a new instance of your app. This is changing in Xcode 8 with the new xcodebuild. You’ll be able to specify a pre-compiled bundle of tests to be run against a freshly-compiled instance of your app. This has the potential to vastly reduce your compile times. By default (at least in Xcode 7), all of your tests will go into the same target. Each time you need to run your tests, your entire app and all the tests will be recompiled. This isn’t always efficient, especially if there are pieces of your app that haven’t changed. With this new feature of Xcode 8, you’ll be able segregate these tests on their own, so that they can still be run, but they don’t have to be compiled. Awesome.

Faster Test Indexing

Xcode 8 testing features

In Xcode 7, it’s really frustrating when I open a project in Xcode, and I have to wait several minutes for Xcode to finish “Indexing” my tests before I can run them. Have you experienced this? Seeing that I’m only working with a couple projects at a time, and the number of my tests creeps up slowly as I work on the projects, there really isn’t a huge cliff where performance all of a sudden drops off. Instead, one day, it will catch my eye that I noticed the indexing took longer than usual, or got in my way from actually performing a build. Then I wait. And eventually I can resume what I intended to do.

I was happy to hear that in Xcode 8, Apple has vastly improved the performance of this indexing process. In the Platforms State of the Union, it was stated that there is a 50x speed increase when tests are indexed. I can’t wait to experience this in my real projects during my day to day development.

It’s been great to watch how Apple’s support of automated testing has evolved over the years, and these three new Xcode 8 testing features continue that trend. You can measure tangible jumps in automated testing support with each WWDC since the iPhone’s original introduction. I can’t wait to see what else the rest of the week holds with regards to further enhancements to testing in Xcode 8.

Happy cleaning.

Xcode Extensions- Your Life Will Change

Did you get a chance to watch the WWDC 2016 Keynote or Platforms State of the Union today? Or were you lucky enough to be there in person? I wanted to bring to your attention what I believe will be one of the most impactful changes to your life as a developer, Xcode Extensions. In fact, Apple didn’t actually even mention it aloud during the keynote. You had to be closely watching the slides. Xcode Extensions appeared in the slide that Craig Federighi presented that was tag-cloud like in showing off all the new developer features available for iOS10. You can see it at minute mark 100:48. Xcode Extensions are also featured prominently on the What’s New page for Xcode 8:

xcode extensions

Later in the day, Xcode Extensions got a solid shoutout and description during the Platforms State of the Union, which you can see at minute mark 37:38.

Third Party Extensions Have Been Hard

Overall, during the keynote, I was a little surprised by the lack of new APIs available to iOS developers that were presented during this keynote. So when this slide appeared highlighting the new features available to iOS developers, I paused the video to scour each bullet. I’ve always loved customizing my development environment, and I’ve been a Alcatraz user for years. Alcatraz is a third-party extension (or plugin) manager for Xcode plugins. You can get anything from different source code highlighting templates, to extensions that significantly change the behavior of Xcode (usually in good ways). Unfortunately, creating Xcode extensions up until now has not been supported by Apple. I had the honor of working with Derek Selander on his monster 3-part tutorial on creating your own Xcode Plugin (I tech edited the article), and it revealed just how hard it is to create an Xcode extension, up until now. It’s a huge pain in the butt, and is really hard to do. You end up decompiling assembly code, running multiple instances of Xcode, and end up guessing a lot. And then, when new versions of Xcode are released, it’s possible that your plugin won’t work and will need to be updated.

Officially Supported Xcode Extensions Will Be Awesome

Other IDEs like Android Studio or Eclipse have APIs available for easily creating plugins. I’m assuming that Xcode Extensions are going to be just that, a way for developers to easily create Xcode extensions or plugins, through a Apple-supported API. Looking at the WWDC schedule, now that it’s been declassified, session 414 on Thursday is titled “Using and Extending the Xcode Source Editor.” It’s description contains the following:

We’ll also show you how to add commands to the source editor with new Xcode Extensions that you can distribute on the Mac App Store.

xcode extensions

During the Platforms State of the Union, the following were described as examples of Xcode extension functionality:

  • Content addition and deletion
  • Content transformation
  • Content selection
  • Pasteboard modification
  • In-file navigation

I was happy to see that Xcode extensions will be supported anywhere Xcode 8 runs – on both macOS Sierra and El Capitan. And furthermore, to be able to actually SELL THEM- something which isn’t possible with today’s backwards way of reverse engineering to create your own Xcode extension, will be awesome.

I think this will have a profound effect on our lives as developers. JetBrains and Reveal will no longer need to create standalone apps to help developers. Instead, they’ll be able to provide their awesome 3rd party functionality and features right within Xcode. I can’t wait for Xcode extensions.

Signed Libraries

Remember the hacked version of Xcode called XcodeGhost that was being distributed on third party download sites? Hackers had created a malicious version of Xcode that would inject malicious code into your iOS apps. Luckily, this only ever made it onto 3rd party download sites, which you shouldn’t use anyway, but people still do use because of slow overseas download speeds. The technique used to create Xcode extensions prior to Xcode 8 enabled this type of malicious hackery of Xcode. Luckily, with changes to Xcode 8, this doesn’t look like it will be possible any longer.

Xcode is now secured by System Integrity Protection, which means only trusted libraries and extensions can interact with the IDE and your code.

I interpret this to mean that the “old” way to hacking your own plugins into Xcode will no longer work, and you’ll instead have to play within the boundaries defined for official Xcode extensions.

WWDC week is so exciting. I’ll be going through videos each day and finding exciting and new APIs, features, and SDK changes to relay to you here, right on What are you finding most exciting?

Happy cleaning.