Question: I created the first unit test target in our `iOS` application by simply clicking through the plus icon inside the test tab on the left navigator.
(The target to be tested is set to the main application)

![Creating a new unit test target](https://i.stack.imgur.com/vRJ82.png)

The unit test target created itself successfully but when I try to run the pre-generated tests, it outputs an error message. The error message displays that the build input file cannot be found. More specifically, the file `/Plugins/XXXTests.xctest/XXXTests` cannot be found. I double checked and in fact that file is not in that directory. 

![Error message when trying to run tests](https://i.stack.imgur.com/dL9o6.png)

While I could not find anything similar to this problem, I tried everything that was close to it but nothing seemed to fix problem. 

Any help would be greatly appreciated!

Answer: 
For me, it was because the test source files are not included in the test target. 

Including those test files in the test target solved it.
Do you have it set properly in schemes? 

Go to `Product -> Scheme -> Edit Scheme -> Test` and check, if your test target is properly added to the correct scheme. It should look something like this: 
[![enter image description here](https://i.stack.imgur.com/ZqyqV.png)](https://i.stack.imgur.com/ZqyqV.png)