Just realised that this could be mergable since the existing infrastructure is not modified!

Another approach to trying to make the bash sections more testable and reusable is to create bash functions, pop them in a file (say functions/thinkofagoodname.sh) and then make sure those functions are in a file that bash will source that file every time it is invoked.

One way to do that is an approach like this:

https://github.com/marketplace/actions/action-setup-bash

which is an action that dumps a function into .bash_profile and sets the default bash to use --login and so source that file.

An example function:

$ cat extract_version.sh 
extract_version() {

   if [ "$#" -ne 2 ]; then
      echo "Illegal number of parameters"
      return 1
   fi

   local node=$1
   local spackyaml=$2

   echo $(yq "${node} | split(\"@git.\") | .[1]" ${spackyaml})

}

Now you could have a bunch of files, one for each function and dump them all into .bash_profile, or put them all in a single file.

Could then have some specialist CI that only gets called when files in that subdirectory changes to test the functions.