Add code coverage workflow

Author: wpscholar

.github/workflows/code-coverage.yml

@@ -0,0 +1,52 @@
+name: Update Code Coverage
+
+on:
+  push:
+    branches:
+      - main
+    paths:
+      - "**.php"
+      - "composer.json"
+      - "composer.lock"
+      - "phpunit.xml"
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        php-version: ["7.2", "7.3", "7.4", "8.0", "8.1", "8.2", "8.3"]
+
+    name: PHP ${{ matrix.php-version }}
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+
+      - name: Set up Node.js
+        uses: actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020 # v4.4.0
+        with:
+          node-version: "22"
+
+      - name: Set up PHP
+        uses: shivammathur/setup-php@cf4cade2721270509d5b1c766ab3549210a39a2a #2.33.0
+        with:
+          php-version: "7.4"
+
+      - name: Install npm dependencies
+        run: npm ci
+
+      - name: Install Composer dependencies
+        run: composer install --prefer-dist --no-interaction --no-progress
+
+      - name: Run wp-env and PHPUnit tests
+        run: |
+          npm run env:start
+          npm run test:coverage
+
+      - name: Upload coverage to Codecov
+        uses: codecov/codecov-action@v5
+        with:
+          files: ./coverage.xml
+          fail_ci_if_error: true
+          token: ${{ secrets.CODECOV_TOKEN }}