improve style bot comment (notify earlier and update later) (#3179)

* explicit

* explicit

---------

Co-authored-by: ydshieh <ydshieh@users.noreply.github.com>

Author: ydshieh

.github/workflows/style-bot-action.yml

@@ -90,7 +90,7 @@ jobs:
         
       - name: Check out PR branch
         uses: actions/checkout@v3
-        env: 
+        env:
           HEADREPOFULLNAME: ${{ steps.pr_info.outputs.headRepoFullName }}
           HEADREF: ${{ steps.pr_info.outputs.headRef }}
         with:
@@ -100,7 +100,7 @@ jobs:
           # You may need fetch-depth: 0 for being able to push
           fetch-depth: 0
           token: ${{ secrets.bot_token }}
-      
+
       - name: Check commit timestamps
         env:
           COMMENT_DATE: ${{ github.event.comment.created_at }}
@@ -132,6 +132,24 @@ jobs:
             echo "--- Checking out contributor branch ($HEADREF) ---"
             git checkout $HEADREF
 
+      - name: Comment on PR with workflow run link
+        id: init_comment
+        uses: actions/github-script@v6
+        with:
+          script: |
+            const prNumber = parseInt(process.env.prNumber, 10);
+            const runUrl = `${process.env.GITHUB_SERVER_URL}/${process.env.GITHUB_REPOSITORY}/actions/runs/${process.env.GITHUB_RUN_ID}`
+
+            const { data: botComment } = await github.rest.issues.createComment({
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              issue_number: prNumber,
+              body: `Style fix is beginning .... [View the workflow run here](${runUrl}).`
+            });
+            core.setOutput('comment_id', botComment.id);
+        env:
+          prNumber: ${{ steps.pr_info.outputs.prNumber }}
+
       - name: Set up Python
         uses: actions/setup-python@v4
         with:
@@ -143,6 +161,7 @@ jobs:
         run: |
           python -m pip install --upgrade pip
           pip install .$python_quality_dependencies
+          echo ${{ steps.init_comment.outputs.comment_id }}
 
       - name: Run style command
         id: run_style
@@ -169,7 +188,7 @@ jobs:
 
       - name: Commit and push changes
         id: commit_and_push
-        env: 
+        env:
           HEADREPOFULLNAME: ${{ steps.pr_info.outputs.headRepoFullName }}
           HEADREF: ${{ steps.pr_info.outputs.headRef }}
           PRNUMBER: ${{ steps.pr_info.outputs.prNumber }}
@@ -195,19 +214,27 @@ jobs:
             echo "changes_pushed=false" >> $GITHUB_OUTPUT
           fi
 
-      - name: Comment on PR with workflow run link
-        if: steps.commit_and_push.outputs.changes_pushed == 'true'
+      - name: Prepare final comment message
+        id: prepare_final_comment
+        run: |
+          if [ "${{ steps.commit_and_push.outputs.changes_pushed }}" = 'true' ]; then
+            echo "final_comment=Style bot fixed some files and pushed the changes." >> $GITHUB_OUTPUT
+          else
+            echo "final_comment=Style fix runs successfully without any file modified." >> $GITHUB_OUTPUT
+          fi
+
+      - name: Comment on PR
         uses: actions/github-script@v6
         with:
           script: |
             const prNumber = parseInt(process.env.prNumber, 10);
             const runUrl = `${process.env.GITHUB_SERVER_URL}/${process.env.GITHUB_REPOSITORY}/actions/runs/${process.env.GITHUB_RUN_ID}`
 
-            await github.rest.issues.createComment({
+            await github.rest.issues.updateComment({
               owner: context.repo.owner,
               repo: context.repo.repo,
-              issue_number: prNumber,
-              body: `Style fixes have been applied. [View the workflow run here](${runUrl}).`
+              comment_id: ${{ steps.init_comment.outputs.comment_id }},
+              body: `${{ steps.prepare_final_comment.outputs.final_comment }}`
             });
         env:
           prNumber: ${{ steps.pr_info.outputs.prNumber }}