I have an app that has been working perfectly, and without changing anything (so I think) it suddenly refuses to build and gives me this error:
error: unable to open executable '/Users/WillOakley/Library/Developer/Xcode/DerivedData/Will_Oakley_-_WWDC_Swift-amsddfazstgmxvaboibijapkormw/Build/Products/Debug-iphonesimulator/Will Oakley - WWDC SwiftTests.xctest/Will Oakley - WWDC SwiftTests': No such file or directory
I have no idea what that file is and what I could have done to move/delete it. Is there any way to force Xcode to regenerate whatever this file is?
This issue was discussed in the below stackoverflow question, Unable to open executable - xcode
the top response provided by them is given below, try to follow the steps and it should solve your problem,
I have also faced that problem. I have closed, restarted Xcode; deleted the application from device and reinstalled it again, then the problem has gone. Make sure the library and project files is truly included if it is not include it shows in red color in this type of case some time it is in original folder and not in project so delete it and add it again.