Update format.yml

Author: neetcode-gh

.github/workflows/format.yml

@@ -1,66 +1,127 @@
 name: Format Files
 
-# cpp
-# csharp - https://github.com/dotnet/format ?
-# java - prettier-plugin-java
-# javascript - prettier
-# python - black
-# ruby - rufo
-# swift - https://github.com/apple/swift-format ?
-# typescript  - prettier
-
 on:
   workflow_dispatch:
-  pull_request_target:
+  pull_request:
     types: [opened, synchronize, reopened]
 
+permissions:
+  contents: write   # write needed only for same-repo pushes; forks get read-only token automatically
+
 jobs:
-  Format:
+  format:
     runs-on: ubuntu-latest
 
-    strategy:
-      matrix:
-        node-version: [20.x]
-
     steps:
-      - name: Checkout Repository
+      - name: Checkout PR HEAD
         uses: actions/checkout@v4
         with:
-          ref: ${{ github.head_ref }}
-          fetch-depth: 1
+          repository: ${{ github.event.pull_request.head.repo.full_name }}
+          ref: ${{ github.event.pull_request.head.sha }}
+          fetch-depth: 0
+
+      - name: Detect fork vs same-repo
+        id: ctx
+        run: |
+          if [ "${{ github.event.pull_request.head.repo.full_name }}" = "${{ github.repository }}" ]; then
+            echo "same_repo=true" >> $GITHUB_OUTPUT
+          else
+            echo "same_repo=false" >> $GITHUB_OUTPUT
+          fi
 
-      - name: Use Node.js (dependency)
+      - name: Use Node.js
         uses: actions/setup-node@v4
         with:
-          node-version: ${{ matrix.node-version }}
+          node-version: 20
 
-      - name: Install Rufo (dependency)
+      - name: Install formatters
         run: |
-          sudo apt update
+          sudo apt-get update
           sudo gem install rufo
-
-      - name: Install Prettier
-        run: |
-          npm install -g prettier
-          npm install -g prettier-plugin-java
-
+          npm i -g prettier prettier-plugin-java
       - name: Install Black
         uses: BSFishy/pip-action@v1
         with:
           packages: black
 
-      - name: Format
+      - name: Run formatters
+        run: |
+          set -e
+          # Use globs; .prettierrc discovered from repo root
+          prettier --write "javascript/*.js" || true
+          prettier --write "typescript/*.ts" || true
+          prettier --write "java/*.java" || true
+          rufo ruby || true
+          python -m black . || true
+
+      - name: Check for changes
+        id: diff
+        run: |
+          git status --porcelain
+          if [ -n "$(git status --porcelain)" ]; then
+            echo "changed=true" >> $GITHUB_OUTPUT
+          else
+            echo "changed=false" >> $GITHUB_OUTPUT
+          fi
+
+      # Auto-push only for same-repo PRs
+      - name: Push formatting changes (same-repo only)
+        if: steps.ctx.outputs.same_repo == 'true' && steps.diff.outputs.changed == 'true'
+        run: |
+          git config user.email "[email protected]"
+          git config user.name "Bot-A0"
+          git add -A
+          git commit -m "🎨 Format files (🛠️ from GitHub Actions)"
+          git push "https://x-access-token:${GITHUB_TOKEN}@github.com/${{ github.event.pull_request.head.repo.full_name }}.git" \
+            HEAD:refs/heads/${{ github.event.pull_request.head.ref }}
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+
+      # For forks, upload a patch artifact the author can apply locally: `git apply formatting.patch`
+      - name: Create patch (forks only)
+        if: steps.ctx.outputs.same_repo == 'false' && steps.diff.outputs.changed == 'true'
         run: |
-          prettier --config "$GITHUB_WORKSPACE/.prettierrc" --write "$GITHUB_WORKSPACE/javascript/*.js" 2>&1 || true
-          prettier --config "$GITHUB_WORKSPACE/.prettierrc" --write "$GITHUB_WORKSPACE/typescript/*.ts" 2>&1 || true
-          prettier --config "$GITHUB_WORKSPACE/.prettierrc" --write "$GITHUB_WORKSPACE/java/*.java" 2>&1 || true
-          rufo "$GITHUB_WORKSPACE/ruby" 2>&1 || true
-          python -m black "$GITHUB_WORKSPACE/" 2>&1 || true
+          git diff > formatting.patch
+          ls -l formatting.patch
+
+      - name: Upload patch artifact (forks only)
+        if: steps.ctx.outputs.same_repo == 'false' && steps.diff.outputs.changed == 'true'
+        uses: actions/upload-artifact@v4
+        with:
+          name: formatting.patch
+          path: formatting.patch
+          if-no-files-found: error
+          retention-days: 7
+
+      # Leave a comment with instructions on fork PRs
+      - name: Comment instructions (forks only)
+        if: steps.ctx.outputs.same_repo == 'false' && steps.diff.outputs.changed == 'true'
+        uses: actions/github-script@v7
+        with:
+          script: |
+            const body = [
+              "I ran the formatters and found changes. Since this is a forked PR, I can't push to your branch.",
+              "",
+              "**How to apply the patch:**",
+              "```bash",
+              "curl -L -o formatting.patch \"$ACTIONS_ARTIFACT_URL\"  # Download from the job's Artifacts section",
+              "git apply formatting.patch",
+              "git commit -am \"Apply formatting patch\"",
+              "git push",
+              "```",
+              "",
+              "Alternatively, run the same formatters locally: `prettier`, `rufo`, and `black`."
+            ].join("\n");
+            github.rest.issues.createComment({
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              issue_number: context.payload.pull_request.number,
+              body
+            });
 
-      - name: Push
+      # Optional: make CI fail if formatting changes were needed (forces author to accept fixes or patch)
+      - name: Fail if formatting changes are needed
+        if: steps.diff.outputs.changed == 'true' && steps.ctx.outputs.same_repo == 'false'
         run: |
-          git config --global user.email "[email protected]"
-          git config --global user.name "Bot-A0"
-          git add .
-          git commit -m "🎨 Format files (🛠️ from Github Actions)" || true
-          git push || true
+          echo "Formatting changes required. Patch uploaded as an artifact."
+          exit 1