Question: I've been following Apple's documentation on writing unit tests for the iPhone, and out of the box, the routine doesn't seem to work. I'm not sure I understand where the unit test is going to get the reference to the application delegate. 

My Dependencies are like the following:
My\_Program\_target -> UnitTesting\_target -> UnitTests\_bundle

The following code snippet is where the assert fails. I'm very familiar with CPPUNIT, but I'm having trouble understanding how this crosses over.

```
- (void) testAppDelegate {

    id yourApplicationDelegate = [[UIApplication sharedApplication] delegate];
    STAssertNotNil(yourApplicationDelegate, @"UIAppliation failed to find the AppDelegate");

}

```

Additionally:

I've decided in my approach to do a logic test. I'm trying to read in an XML file, but I'm not having luck resolving the bundle, which will provide me with the path by which I can access my file. I've tried pasting in the path output by allBundles, but that path doesn't seem to work either. Below is what I'm executing in my test (you can see the debug statement I'm using to output the paths of the bundles):

```
NSLog(@"BundlePaths: %@", [NSBundle allBundles]);
   NSString * path = [[NSBundle bundleWithPath:@"$(TARGET_BUILD_DIR)"] pathForResource:@"SimpleTestList" ofType:@"plist"];
   STAssertNotNil(path, @"Bundle Location couldn't find the file specified");

```

Essentially, the assert on path is not successful, but I'm not sure what to put for the path or directory to reference my unitTest bundle that I've told to copy the bundle resources. Calling [NSBundle mainBundle] does not work either.

Answer: 
Ok, so I've figured it out. In order to open a file in a unit test, you'll need to specify the file to open as:

```
NSString * filePath = [[NSBundle bundleForClass:[self class] ] pathForResource:@"SimpleTestList" ofType:@"plist"];

```

If you include this in a class that's compiled as part of your unit test bundle, that class will look inside the unit test bundle for the file SimpleTestList.plist.

For a unit test, just make sure you set up "Copy Bundle Resources" to include your plist in your unit test bundle.
The Swift 3 translation of Gary's answer above (using an URL instead of a string path) is:

```
let url = Bundle(for: type(of: self)).url(forResource: "SimpleTestList", withExtension: "plist")

```

Notice the critical and non-obvious part **`type(of: self)`** instead of `[self class]`.