Add automatic code style for new PR. (#1047)

.github/build/.gitignore

@@ -0,0 +1,2 @@
+*
+!.gitignore

.github/workflows/php-cs-fixer.yml

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+name: php-cs-fixer
+on: [push, pull_request]
+env:
+  PR_NUMBER: "${{ github.event.number }}"
+  SOURCE_BRANCH: "$GITHUB_HEAD_REF"
+  FIXER_BRANCH: "auto-fixed/$GITHUB_HEAD_REF"
+  TITLE: "Apply fixes from PHP-CS-Fixer"
+  DESCRIPTION: "This merge request applies PHP code style fixes from an analysis carried out through GitHub Actions."
+jobs:
+  php-cs-fixer:
+    if: github.event_name == 'pull_request' && ! startsWith(github.ref, 'refs/heads/auto-fixed/')
+    runs-on: ubuntu-20.04
+    name: Run PHP CS Fixer
+    steps:
+      - name: Checkout Code
+        uses: actions/checkout@v2
+      - name: Setup PHP
+        uses: shivammathur/[email protected]
+        with:
+          php-version: 7.4
+          extensions: json, dom, curl, libxml, mbstring
+          coverage: none
+      - name: Install PHP-CS-Fixer
+        run: |
+          curl -L https://github.com/FriendsOfPHP/PHP-CS-Fixer/releases/download/v2.18.6/php-cs-fixer.phar -o .github/build/php-cs-fixer
+          chmod a+x .github/build/php-cs-fixer
+      - name: Prepare Git User
+        run: |
+          git config --global user.name "github-actions[bot]"
+          git config --global user.email "[email protected]"
+          git checkout -B "${{ env.FIXER_BRANCH }}"
+      - name: Apply auto-fixers
+        run: php .github/build/php-cs-fixer fix --config=.php_cs
+      - name: Create Fixer PR
+        run: |
+          if [[ -z $(git status --porcelain) ]]; then
+            echo "Nothing to fix.. Exiting."
+            exit 0
+          fi
+          OPEN_PRS=`curl --silent -H "Accept: application/vnd.github.v3+json" -H "Authorization: Bearer ${{ secrets.GITHUB_TOKEN }}" "https://api.github.com/repos/$GITHUB_REPOSITORY/pulls?state=open"`
+          OPEN_FIXER_PRS=`echo ${OPEN_PRS} | grep -o "\"ref\": \"${{ env.FIXER_BRANCH }}\"" | wc -l`
+          git commit -am "${{ env.TITLE }}"
+          git push origin "${{ env.FIXER_BRANCH }}" --force
+          if [ ${OPEN_FIXER_PRS} -eq "0" ]; then
+            curl -X POST \
+              -H "Accept: application/vnd.github.v3+json" \
+              -H "Authorization: Bearer ${{ secrets.GITHUB_TOKEN }}" \
+              "https://api.github.com/repos/$GITHUB_REPOSITORY/pulls" \
+              -d "{ \"head\":\"${{ env.FIXER_BRANCH }}\", \"base\":\"${{ env.SOURCE_BRANCH }}\", \"title\":\"${{ env.TITLE }}\", \"body\":\"${{ env.DESCRIPTION }}\n\nTriggered by #${{ env.PR_NUMBER }}\" }"
+          fi
+          exit 1