Add action to modify external GitHub repo

github-modify/action.yml

@@ -0,0 +1,48 @@
+---
+# yamllint disable rule:line-length
+name: 'Modify external repo to checkout from'
+description: "Modify external repo to check out from"
+inputs:
+  repo:
+    description: "The name of the GitHub repo"
+    required: true
+    type: string
+runs:
+  using: "composite"
+  steps:
+    - name: Check out jbaublitz/${{ inputs.repo }}
+      if: github.event_name == 'pull_request'
+      id: jbaublitz
+      continue-on-error: true
+      uses: actions/checkout@v4
+      with:
+        repository: jbaublitz/${{ inputs.repo }}
+        path: jbaublitz
+        ref: ${{ github.head_ref }}
+    - name: Check out mulkieran/${{ inputs.repo }}
+      if: github.event_name == 'pull_request'
+      id: mulkieran
+      continue-on-error: true
+      uses: actions/checkout@v4
+      with:
+        repository: mulkieran/${{ inputs.repo }}
+        path: mulkieran
+        ref: ${{ github.head_ref }}
+    - name: Check if both checkouts succeeded
+      if: github.event_name == 'pull_request' && steps.jbaublitz.outcome == 'success' && steps.mulkieran.outcome == 'success'
+      run: |
+        echo "Branch conflict!"
+        exit 1
+    - name: Conditionally make jbaublitz checkout branch the chosen one
+      if: github.event_name == 'pull_request' && steps.jbaublitz.outcome == 'success'
+      run: mv jbaublitz ${{ inputs.repo }}
+    - name: Conditionally make mulkieran checkout branch the chosen one
+      if: github.event_name == 'pull_request' && steps.mulkieran.outcome == 'success'
+      run: mv mulkieran ${{ inputs.repo }}
+    - name: Check out stratis-storage repo if no alternative branch was checked out
+      if: github.event_name != 'pull_request' || (github.event_name == 'pull_request' && steps.mulkieran.outcome == 'failure' && steps.jbaublitz.outcome == 'failure')
+      uses: actions/checkout@v4
+      with:
+        repository: stratis-storage/${{ inputs.repo }}
+        path: ${{ inputs.repo }}
+        ref: master