How to undo xcode discard all changes if not committed

You might not be out of luck. Although Git can't help you, Finder may be able to come to the rescue!

If you have not turned off the Versions feature (which by default is turned on and you need a Terminal command to disable), then do the following:

1. Quit Xcode.
2. Open the file you wish to bring back your lost changes to using TextEdit.
3. Go to File > Revert To > Browse All Versions...
4. Scroll through the available versions. Hopefully you will have many available to choose from.
5. Select a version and hit Restore.
6. Follow 2-5 for all necessary files.
7. Launch Xcode. You should now see the M next to these files in Project Navigator indicating they include uncommited changes (the changes you previously discarded).

Completely new files you may have created and were discarded can be found in the Trash.

Also a small piece of advice. If you are in need to discard changes, prefer using Source Control > Discard Changes by right clicking on files in the Project Navigator, instead of Discard All Changes which might give you all kinds of trouble.

Have a nice day. :)

If you clicked on "discard changes" before committing any changes, your project will become blank and you will find all files in your trash. There is not an whole xcode project there, but you will find all the files which have dates of when you created them. I solved my issue by getting the file I needed from trash. Then I put it back into my project.