I am trying to do user authentication if a pull request contain changes in certain folders. I am intending to do this even before GitHub actions are triggered using pre-build script. I am able to access the user information using the environment variable github_event_path and extract author using jq.
Now I am not able to find a way to get changed files(thus finding out what folder a change is made, based on the absolute path) in this pre-build shell script. I tried using ${{steps.files.outputs.all}} that is used in getting the changed files in GitHub actions. I think steps is not accessible in pre-build shell scripts as I got bad substitution error.