feat: enhance error handling for non-git directories (#1885)

Co-authored-by: GitHub Action <action@github.com>

.github/workflows/test.yml

@@ -550,6 +550,39 @@ jobs:
         shell:
           bash
 
+  test-non-existing-repository:
+    name: Test changed-files with non existing repository
+    runs-on: ubuntu-latest
+    needs: build
+    if: github.event_name == 'push' && needs.build.outputs.files_changed != 'true'
+    permissions:
+      pull-requests: read
+    steps:
+      - name: Checkout into dir1
+        uses: actions/checkout@v4
+        with:
+          repository: ${{ github.event.pull_request.head.repo.full_name }}
+          submodules: true
+          fetch-depth: 0
+          path: dir1
+
+      - name: Download build assets
+        uses: actions/download-artifact@v3
+        with:
+          name: build-assets
+          path: dir1/dist
+
+      - name: Run changed-files with non existing repository
+        id: changed-files
+        continue-on-error: true
+        uses: ./dir1
+
+      - name: Verify failed
+        if: steps.changed-files.outcome != 'failure'
+        run: |
+          echo "Expected: (failure) got ${{ steps.changed-files.outcome }}"
+          exit 1
+
   test-submodules:
     name: Test changed-files with submodule
     runs-on: ubuntu-latest