Enhance Prettify Code workflow for changed files

Updated the GitHub Actions workflow to fetch the base branch and check code formatting only for changed files in pull requests.

Signed-off-by: Manas Manohar <[email protected]>

Author: manasmanohar

.github/workflows/prettify_code.yml

@@ -1,5 +1,4 @@
 name: Prettify Code
-# This action works with pull requests and pushes
 on:
   pull_request:
   push:
@@ -9,18 +8,41 @@ on:
 jobs:
   prettier:
     runs-on: ubuntu-latest
-
     steps:
       - name: Checkout
         uses: actions/checkout@v4
         with:
           fetch-depth: 0
 
-      - name: Prettify code
+      - name: Fetch base branch
+        if: github.event_name == 'pull_request'
+        run: git fetch origin ${{ github.event.pull_request.base.ref }}
+
+      - name: Get changed files
+        id: changed-files
+        run: |
+          if [ "${{ github.event_name }}" == "pull_request" ]; then
+            BASE_SHA="origin/${{ github.event.pull_request.base.ref }}"
+          else
+            BASE_SHA="${{ github.event.before }}"
+          fi
+          
+          git diff --name-only --diff-filter=ACMR -z $BASE_SHA HEAD | \
+            grep -zE '\.(js|md)$' | \
+            xargs -0 -r echo > changed_files.txt
+          
+          if [ -s changed_files.txt ]; then
+            echo "has_files=true" >> $GITHUB_OUTPUT
+            echo "Changed files:"
+            cat changed_files.txt
+          else
+            echo "has_files=false" >> $GITHUB_OUTPUT
+          fi
+
+      - name: Check code formatting
+        if: steps.changed-files.outputs.has_files == 'true'
         uses: creyD/[email protected]
         with:
-          # This part is also where you can pass other options, for example:
           prettier_version: 2.8.8
-          prettier_options: --write **/*.{js,md}
-          same_commit: true
-          
+          prettier_options: --check $(cat changed_files.txt)
+          dry_run: true