Add PHPStan action

Author: lcharette

.github/workflows/PHPStan.yml

@@ -0,0 +1,33 @@
+name: PHPStan
+
+on:
+  push:
+    branches: [5.0]
+  pull_request:
+    branches: [5.0]
+  workflow_dispatch:
+
+jobs:
+  PHPStan:
+
+    strategy:
+      fail-fast: false
+      matrix:
+        php_versions: ['8.1', '8.2', '8.3']
+
+    runs-on: ubuntu-latest
+    name: PHPStan - ${{ matrix.php_versions }}
+
+    steps:
+    - uses: actions/checkout@v3
+    
+    - name: Setup PHP, with composer and extensions
+      uses: shivammathur/setup-php@v2
+      with:
+        php-version: ${{ matrix.php_versions }}
+
+    - name: Install Dependencies
+      run: composer install --no-ansi --no-interaction --no-scripts --no-progress --prefer-dist
+
+    - name: Run PHPStan
+      run: vendor/bin/phpstan analyse

README.md

@@ -5,6 +5,7 @@
 [![Build](https://img.shields.io/github/actions/workflow/status/userfrosting/UserFrosting/Build.yml?branch=5.1&logo=github)](https://github.com/userfrosting/UserFrosting/actions)
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 [![Style](https://github.styleci.io/repos/18148206/shield?branch=5.1&style=flat)](https://github.styleci.io/repos/18148206)
+[![PHPStan](https://img.shields.io/github/actions/workflow/status/userfrosting/userfrosting/PHPStan.yml?branch=5.1&label=PHPStan)](https://github.com/userfrosting/userfrosting/actions/workflows/PHPStan.yml)
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