fixup! CI: R

Signed-off-by: Mathias L. Baumann <[email protected]>

Author: Marenz

.github/workflows/ci.yaml

@@ -68,7 +68,7 @@ jobs:
         id: restore-pytest-cache
         with:
           path: .pytest_cache
-          key: ${{ format('{0}-pytest-cache-{1}-{2}-{3}-{4}', runner.os, matrix.os, matrix.python, github.ref_name, github.run_number - 1) }}
+          key: ${{ runner.os }}-pytest-cache-${{ matrix.os }}-${{ matrix.python }}-${{ github.ref_name }}
           restore-keys: |
             ${{ runner.os }}-pytest-cache-${{ matrix.os }}-${{ matrix.python }}-${{ github.ref_name }}-
 
@@ -87,6 +87,7 @@ jobs:
 
       # Run nox session
       - name: Run nox
+        id: nox-run
         env:
           NOX_SESSION: ${{ matrix.nox-session }}
         run: |
@@ -97,9 +98,9 @@ jobs:
           fi
         timeout-minutes: 10
 
-      # Save pytest cache only for pytest_min session
+      # Save pytest cache only for pytest_min session and only on failure
       - name: Save pytest cache
-        if: always() && matrix.nox-session == 'pytest_min'
+        if: always() && steps.run-nox.outcome == 'failure' && matrix.nox-session == 'pytest_min'
         uses: actions/cache/save@v4
         with:
           path: .pytest_cache