diff --git a/.github/workflows/bench-diff.yml b/.github/workflows/bench-diff.yml
index 5f6cdc05..4dfe0714 100644
--- a/.github/workflows/bench-diff.yml
+++ b/.github/workflows/bench-diff.yml
@@ -18,16 +18,20 @@ jobs:
     permissions:
       checks: write
     steps:
-    - name: Debug event types
+    - name: Get sha commit
+      id: event
       run: |
-        echo "${{ github.event_name != 'pull_request' && github.sha || github.event.pull_request.head.sha }}"
-        echo "github.sha=${{ github.sha }}"
-        echo "github.event.pull_request.head.sha=${{ github.event.pull_request.head.sha }}"
+        echo "DEBUG: event type(${{ github.event_name }})"
+        if [ "${{ github.event_name != 'pull_request' }}" = "true" ] ; then
+          echo "ref=${{ github.sha }}" >> "$GITHUB_OUTPUT"
+        else
+          echo "ref=${{ github.event.pull_request.head.sha }}" >> "$GITHUB_OUTPUT"
+        fi
     - uses: actions/checkout@v4
       with:
         fetch-depth: 0
         persist-credentials: false
-        ref: ${{ github.event_name != 'pull_request' && github.sha || github.event.pull_request.head.sha }}
+        ref: ${{ steps.event.outputs.ref }}
     - uses: actions/setup-go@v5
       with:
         go-version-file: go.mod
@@ -36,7 +40,7 @@ jobs:
       id: benchdiff
       with:
         benchdiff_version: 0.9.1
-        status_sha: ${{ github.event_name != 'pull_request' && github.sha || github.event.pull_request.head.sha }}
+        status_sha: ${{ steps.event.outputs.ref }}
         status_name: benchdiff-result
         status_on_degraded: neutral
         # See https://github.com/WillAbides/benchdiff