ci: expose python version for translate tests (#178)

With NDSL supporting more than one version of python, we'd like to have
the possibility to run pyFV3 translate tests with different versions of
python. This PR adds an optional input variable to the `workflow_call`
which allows calling workflows to specify the python version.

The PR also removes usage of the `component_trigger` input variable. The
input is redundant with `component_name`, which is a non-empty string
whenever `component_trigger` is true. I keep the input around until we
update all calling workflows to not set it anymore.

Co-authored-by: Roman Cattaneo <>

Author: romanc

.github/workflows/main_unit_tests.yaml

@@ -12,6 +12,10 @@ on:
         type: string
         default: ''
         required: false
+      python_version:
+        type: string
+        default: ''
+        required: false
   pull_request: # ... a PR is opened / updated
   merge_group:  # ... the PR is added to the merge queue
   push:
@@ -29,20 +33,23 @@ jobs:
     defaults:
       run:
         shell: bash -el {0}
+    env:
+      python_default: '3.11'
+
     steps:
       - name: "External trigger: Checkout pace/develop"
-        if: ${{ inputs.component_trigger }}
+        if: ${{ inputs.component_name }}
         uses: actions/checkout@v6
         with:
           submodules: 'recursive'
           repository: NOAA-GFDL/pace
           path: pace
           ref: develop
 
-      - name: Setup Python 3.11
+      - name: 'Setup Python ${{ inputs.python_version && inputs.python_version || env.python_default }}'
         uses: actions/setup-python@v6
         with:
-          python-version: '3.11'
+          python-version: ${{ inputs.python_version && inputs.python_version || env.python_default }}
 
       - name: Install mpi (MPICH flavor)
         run: pip install mpich
@@ -55,7 +62,7 @@ jobs:
         run: pip install numpy==1.26.4
 
       - name: "External trigger: Remove existing component in pace/develop"
-        if: ${{ inputs.component_trigger }}
+        if: ${{ inputs.component_name }}
         run: rm -rf ${GITHUB_WORKSPACE}/pace/${{inputs.component_name}}
 
       - name: Checkout out hash that triggered CI