Print executed command in debug mode (#72)

Supersedes #48

Co-authored-by: Ian Butterworth <i.r.butterworth@gmail.com>

README.md

@@ -11,7 +11,12 @@ An example workflow that uses this action might look like this:
 ```yaml
 name: Run tests
 
-on: [push, pull_request]
+on: 
+  push:
+    branches:
+      - master
+      - main
+  pull_request:
 
 jobs:
   test:

action.yml

@@ -66,10 +66,11 @@ runs:
         julia_cmd=( julia --color=yes --depwarn=${{ inputs.depwarn }} --inline=${{ inputs.inline }} --project=${{ inputs.project }} -e 'include(joinpath(ENV["GITHUB_ACTION_PATH"], "test_harness.jl"))' )
 
         # Add the prefix in front of the command if there is one
-        prefix="${{ inputs.prefix }}"
+        prefix=( ${{ inputs.prefix }} )
-        [[ -n $prefix ]] && julia_cmd=( "$prefix" "${julia_cmd[@]}" )
+        [[ -n ${prefix[*]} ]] && julia_cmd=( "${prefix[@]}" "${julia_cmd[@]}" )
 
         # Run the Julia command
+        echo "::debug::Executing Julia: ${julia_cmd[*]}"
         "${julia_cmd[@]}"
       shell: bash
       env: