Enhancement: Run friendsofphp/php-cs-fixer on GitHub Actions

.github/CONTRIBUTING.md

@@ -67,6 +67,13 @@ about what you're working on, you can contact us via the
   ```
 
   to check your change doesn't break other features.
+- Run
+
+  ```
+  make coding-standards
+  ```
+
+  to automatically fix coding standard issues.
 - Review the change once more just before submitting it.
 
 ## What happens after submitting contribution?
@@ -121,6 +128,12 @@ Having said that, here are the organizational rules:
    make tests
    ```
 
+5. Fix coding standard issues before committing code. To do so use
+
+   ```
+   make coding-standards
+   ```
+
 6. Use reasonable commit messages.
 
 Thank you for contributing to https://www.php.net!

.github/workflows/integrate.yaml

@@ -9,6 +9,49 @@ on:
       - "master"
 
 jobs:
+  coding-standards:
+    name: "Coding Standards"
+
+    runs-on: "ubuntu-latest"
+
+    strategy:
+      matrix:
+        php-version:
+          - "7.3"
+
+    steps:
+      - name: "Checkout"
+        uses: "actions/checkout@v3"
+
+      - name: "Set up PHP"
+        uses: "shivammathur/setup-php@v2"
+        with:
+          coverage: "none"
+          extensions: "none, json, mbstring, tokenizer"
+          php-version: "${{ matrix.php-version }}"
+
+      - name: "Set up problem matchers for PHP"
+        run: "echo \"::add-matcher::${{ runner.tool_cache }}/php.json\""
+
+      - name: "Validate composer.json and composer.lock"
+        run: "composer validate --ansi --strict"
+
+      - name: "Determine composer cache directory"
+        run: "echo \"COMPOSER_CACHE_DIR=$(composer config cache-dir)\" >> $GITHUB_ENV"
+
+      - name: "Cache dependencies installed with composer"
+        uses: "actions/cache@v3"
+        with:
+          path: "${{ env.COMPOSER_CACHE_DIR }}"
+          key: "php-${{ matrix.php-version }}-composer-${{ hashFiles('composer.lock') }}"
+          restore-keys: "php-${{ matrix.php-version }}-composer-"
+
+      - name: "Install dependencies with composer"
+        run: "composer install --ansi --no-interaction --no-progress"
+
+      - name: "Run friendsofphp/php-cs-fixer"
+        run: "vendor/bin/php-cs-fixer fix --ansi --config=.php-cs-fixer.php --diff --dry-run --verbose"
+
   tests:
     name: "Tests"
 

.gitignore

@@ -4,6 +4,8 @@ backend/mirror.gif
 backend/mirror.png
 backend/mirror.jpg
 backend/GeoIP.dat
+vendor/
 .idea
 .DS_Store
 .DS_Store?
+.php-cs-fixer.cache

.php-cs-fixer.php

@@ -0,0 +1,14 @@
+<?php
+
+$finder = PhpCsFixer\Finder::create()->in(__DIR__);
+
+$config = new PhpCsFixer\Config();
+
+$finder = $config->getFinder()
+    ->ignoreDotFiles(false)
+    ->in(__DIR__)
+    ->name(__FILE__);
+
+$config->setRules([]);
+
+return $config;

Makefile

@@ -2,6 +2,14 @@
 help: ## Displays this list of targets with descriptions
 	@grep -E '^[a-zA-Z0-9_-]+:.*?## .*$$' $(MAKEFILE_LIST) | sort | awk 'BEGIN {FS = ":.*?## "}; {printf "\033[32m%-30s\033[0m %s\n", $$1, $$2}'
 
+.PHONY: coding-standards
+coding-standards: vendor ## Fixes code style issues with friendsofphp/php-cs-fixer
+	vendor/bin/php-cs-fixer fix --config=.php-cs-fixer.php --diff --verbose
+
 .PHONY: tests
 tests: ## Runs tests
 	php tests/run-tests.php -j3 -q
+
+vendor: composer.json composer.lock
+	composer validate --strict
+	composer install --no-interaction --no-progress

composer.json

@@ -10,6 +10,9 @@
     "require": {
         "php": "^7.3"
     },
+    "require-dev": {
+        "friendsofphp/php-cs-fixer": "^3.4.0"
+    },
     "autoload": {
         "psr-4": {
             "phpweb\\": "src/"