Add PHPUnit testing framework and error checking documentation

.github/workflows/phpunit.yml

@@ -0,0 +1,61 @@
+name: PHPUnit Tests
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+    branches: [ main ]
+
+permissions:
+  contents: read
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  test:
+    name: PHP ${{ matrix.php }} - WP ${{ matrix.wp }} - ${{ matrix.multisite && 'Multisite' || 'Single Site' }}
+    runs-on: ubuntu-latest
+    
+    strategy:
+      matrix:
+        php: [ '7.4', '8.0' ]
+        wp: [ 'latest' ]
+        multisite: [ false, true ]
+    
+    services:
+      mysql:
+        image: mysql:5.7
+        env:
+          MYSQL_ROOT_PASSWORD: root
+          MYSQL_DATABASE: wordpress_test
+        ports:
+          - 3306:3306
+        options: --health-cmd="mysqladmin ping" --health-interval=10s --health-timeout=5s --health-retries=3
+    
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # v4.1.7
+      
+      - name: Setup PHP
+        uses: shivammathur/setup-php@e6f75134d35752277f093989e72e140eaa222f35 # v2.30.0
+        with:
+          php-version: ${{ matrix.php }}
+          extensions: dom, curl, libxml, mbstring, zip, pdo, mysql, pdo_mysql, bcmath, soap, intl, gd, exif, iconv
+          coverage: none
+      
+      - name: Install Composer dependencies
+        uses: ramsey/composer-install@83af392bf5f031813d25e6fe4cd626cdba9a2df6 # v2.2.0
+      
+      - name: Install WordPress test suite
+        run: |
+          bash bin/install-wp-tests.sh wordpress_test root root 127.0.0.1 ${{ matrix.wp }} ${{ matrix.multisite && 'true' || 'false' }}
+      
+      - name: Run PHPUnit tests
+        run: |
+          if [ "${{ matrix.multisite }}" = "true" ]; then
+            WP_MULTISITE=1 composer test
+          else
+            composer test
+          fi

.wiki/Error-Checking-Feedback-Loops.md

@@ -0,0 +1,126 @@
+# Error Checking and Feedback Loops
+
+This document explains how to check for code quality issues and get feedback from automated tools in our development workflow.
+
+## Table of Contents
+
+* [Overview](#overview)
+* [Local Error Checking](#local-error-checking)
+* [CI/CD Feedback Loops](#cicd-feedback-loops)
+* [Common Issues and Solutions](#common-issues-and-solutions)
+* [Improving Code Quality](#improving-code-quality)
+
+## Overview
+
+Our development process includes multiple layers of error checking and feedback loops to ensure high code quality:
+
+1. **Local Development**: Run linters and tests locally before committing
+2. **Pull Request**: Automated checks run when you create or update a PR
+3. **Code Review**: Human reviewers provide feedback on your code
+4. **Continuous Integration**: Tests run in various environments to ensure compatibility
+
+## Local Error Checking
+
+### PHP Code Quality Checks
+
+Run these commands locally to check for PHP code quality issues:
+
+```bash
+# Run all PHP code quality checks
+npm run lint:php
+
+# Run specific checks
+npm run lint:phpcs    # PHP CodeSniffer
+npm run lint:phpstan  # PHPStan static analysis
+npm run lint:phpmd    # PHP Mess Detector
+```
+
+### JavaScript/CSS Checks
+
+```bash
+# Run ESLint for JavaScript files
+npm run lint:js
+
+# Run stylelint for CSS files
+npm run lint:css
+```
+
+### Running Tests Locally
+
+```bash
+# Run Cypress tests for single site
+npm run test:playground:single
+
+# Run Cypress tests for multisite
+npm run test:playground:multisite
+```
+
+## CI/CD Feedback Loops
+
+When you push code or create a pull request, several automated checks run:
+
+### GitHub Actions Workflows
+
+* **Code Quality**: Runs PHP CodeSniffer, PHPStan, and PHP Mess Detector
+* **WordPress Tests**: Runs tests in WordPress environments
+* **WordPress Playground Tests**: Runs tests in WordPress Playground environments
+* **Tests - Run PHP compatibility and unit tests**: Checks compatibility with different PHP versions
+
+### Third-Party Code Quality Services
+
+* **CodeFactor**: Provides automated code reviews and quality grades
+* **Codacy**: Analyzes code quality and security issues
+* **SonarCloud**: Detects bugs, vulnerabilities, and code smells
+
+## Common Issues and Solutions
+
+### PHP CodeSniffer Issues
+
+* **Indentation**: Use tabs for indentation in PHP files
+* **Spacing**: Add spaces after commas, around operators, and after control structures
+* **Naming Conventions**: Use snake_case for functions and variables in PHP
+* **DocBlocks**: Add proper documentation for functions and classes
+
+### PHPStan Issues
+
+* **Undefined Variables**: Ensure all variables are defined before use
+* **Type Errors**: Use proper type hints and return types
+* **Null Checks**: Add null checks for variables that might be null
+
+### JavaScript/CSS Issues
+
+* **ESLint Errors**: Follow JavaScript best practices
+* **Stylelint Errors**: Follow CSS best practices
+* **Accessibility Issues**: Ensure UI elements are accessible
+
+## Improving Code Quality
+
+### Best Practices
+
+* **Write Tests First**: Use test-driven development (TDD) when possible
+* **Small PRs**: Keep pull requests small and focused on a single issue
+* **Regular Commits**: Commit frequently with clear messages
+* **Code Reviews**: Request code reviews from team members
+* **Documentation**: Keep documentation up-to-date
+
+### Using AI Assistants
+
+AI assistants can help you understand and fix code quality issues:
+
+1. Copy the error message or feedback
+2. Paste it into your AI assistant chat
+3. Ask for help understanding and fixing the issue
+4. Apply the suggested fixes
+5. Run the checks again to verify the issue is resolved
+
+### Continuous Learning
+
+* Review the code quality reports regularly
+* Learn from feedback and improve your coding practices
+* Stay updated on best practices for WordPress development
+
+## Related Documentation
+
+* [Testing Framework](Testing.md)
+* [Code Review Guide](../.ai-workflows/code-review.md)
+* [Architecture Overview](Architecture-Overview.md)

.wiki/Testing.md

@@ -12,6 +12,7 @@ This document explains how to use the testing framework for our plugin.
 * [Writing Tests](#writing-tests)
 * [CI/CD Integration](#cicd-integration)
 * [Troubleshooting](#troubleshooting)
+* [PHPUnit Tests](#phpunit-tests)
 * [Future Improvements](#future-improvements)
 
 ## Overview
@@ -200,15 +201,56 @@ We have GitHub Actions workflows for running tests in CI/CD:
 1. **Docker not running**: Make sure Docker is running before starting wp-env
 2. **Port conflicts**: If ports 8888 or 8889 are in use, wp-env will fail to start
 3. **wp-env not installed**: Run `npm install -g @wordpress/env` to install wp-env globally
+4. **WordPress Playground not loading**: Check your network connection and try refreshing the page
+5. **Tests failing**: Check the error messages in the console and fix the issues
+
+### Error Checking and Feedback Loops
+
+For detailed information on how to check for code quality issues and get feedback from automated tools, see the [Error Checking and Feedback Loops](Error-Checking-Feedback-Loops.md) documentation.
 
 ### Debugging
 
 1. **Cypress debugging**: Use `cy.debug()` to pause test execution
 2. **wp-env debugging**: Run `wp-env logs` to see WordPress logs
+3. **GitHub Actions debugging**: Check the workflow logs for detailed error messages
+
+## PHPUnit Tests
+
+We use PHPUnit for unit testing PHP code. The tests are located in the `tests/phpunit` directory.
+
+### Running PHPUnit Tests
+
+```bash
+# Run PHPUnit tests for single site
+npm run test:phpunit
+
+# Run PHPUnit tests for multisite
+npm run test:phpunit:multisite
+```
+
+### Writing PHPUnit Tests
+
+Here's an example of a PHPUnit test for the Multisite class:
+
+```php
+<?php
+class MultisiteTest extends WP_UnitTestCase {
+
+    public function test_is_multisite_compatible() {
+        $multisite = new WP_Plugin_Starter_Template_For_AI_Coding\Multisite\Multisite();
+        $this->assertTrue($multisite->is_multisite_compatible());
+    }
+
+    public function test_get_network_sites() {
+        $multisite = new WP_Plugin_Starter_Template_For_AI_Coding\Multisite\Multisite();
+        $sites = $multisite->get_network_sites();
+        $this->assertIsArray($sites);
+    }
+}
+```
 
 ## Future Improvements
 
-1. **PHPUnit tests**: Add unit tests for PHP code
+1. **Performance tests**: Add performance testing
-2. **Performance tests**: Add performance testing
+2. **Accessibility tests**: Add accessibility testing
-3. **Accessibility tests**: Add accessibility testing
 

bin/install-wp-tests.sh

@@ -0,0 +1,159 @@
+#!/usr/bin/env bash
+
+if [ $# -lt 3 ]; then
+	echo "usage: $0 <db-name> <db-user> <db-pass> [db-host] [wp-version] [skip-database-creation] [multisite]"
+	exit 1
+fi
+
+DB_NAME=$1
+DB_USER=$2
+DB_PASS=$3
+DB_HOST=${4-localhost}
+WP_VERSION=${5-latest}
+SKIP_DB_CREATE=${6-false}
+MULTISITE=${7-false}
+
+WP_TESTS_DIR=${WP_TESTS_DIR-/tmp/wordpress-tests-lib}
+WP_CORE_DIR=${WP_CORE_DIR-/tmp/wordpress/}
+
+download() {
+    if [ `which curl` ]; then
+        curl -s "$1" > "$2";
+    elif [ `which wget` ]; then
+        wget -nv -O "$2" "$1"
+    fi
+}
+
+if [[ $WP_VERSION =~ ^[0-9]+\.[0-9]+\-(beta|RC)[0-9]+$ ]]; then
+	WP_BRANCH=${WP_VERSION%\-*}
+	WP_TESTS_TAG="branches/$WP_BRANCH"
+	WP_TESTS_TAG="tags/$WP_VERSION"
+elif [[ $WP_VERSION =~ ^[0-9]+\.[0-9]+$ ]]; then
+	WP_TESTS_TAG="branches/$WP_VERSION"
+elif [[ $WP_VERSION =~ [0-9]+\.[0-9]+\.[0-9]+ ]]; then
+	if [[ $WP_VERSION =~ [0-9]+\.[0-9]+\.[0] ]]; then
+		# version x.x.0 means the first release of the major version, so strip off the .0 and download version x.x
+		WP_TESTS_TAG="tags/${WP_VERSION%??}"
+	else
+		WP_TESTS_TAG="tags/$WP_VERSION"
+	fi
+elif [[ $WP_VERSION == 'nightly' || $WP_VERSION == 'trunk' ]]; then
+	WP_TESTS_TAG="trunk"
+else
+	# http serves a single offer, whereas https serves multiple. we only want one
+	download http://api.wordpress.org/core/version-check/1.7/ /tmp/wp-latest.json
+	grep '[0-9]+\.[0-9]+(\.[0-9]+)?' /tmp/wp-latest.json
+	LATEST_VERSION=$(grep -o '"version":"[^"]*' /tmp/wp-latest.json | sed 's/"version":"//')
+	if [[ -z "$LATEST_VERSION" ]]; then
+		echo "Latest WordPress version could not be found"
+		exit 1
+	fi
+	WP_TESTS_TAG="tags/$LATEST_VERSION"
+fi
+set -ex
+
+install_wp() {
+
+	if [ -d $WP_CORE_DIR ]; then
+		return;
+	fi
+
+	mkdir -p $WP_CORE_DIR
+
+	if [[ $WP_VERSION == 'nightly' || $WP_VERSION == 'trunk' ]]; then
+		mkdir -p $WP_CORE_DIR
+		download https://wordpress.org/nightly-builds/wordpress-latest.zip  $WP_CORE_DIR/wordpress-nightly.zip
+		unzip -q $WP_CORE_DIR/wordpress-nightly.zip -d $WP_CORE_DIR
+		rm $WP_CORE_DIR/wordpress-nightly.zip
+	else
+		if [ $WP_VERSION == 'latest' ]; then
+			local ARCHIVE_NAME='latest'
+		elif [[ $WP_VERSION =~ [0-9]+\.[0-9]+ ]]; then
+			# https serves multiple offers, whereas http serves single.
+			download https://api.wordpress.org/core/version-check/1.7/ $WP_CORE_DIR/wp-latest.json
+			if [[ $WP_VERSION =~ [0-9]+\.[0-9]+\.[0] ]]; then
+				# version x.x.0 means the first release of the major version, so strip off the .0 and download version x.x
+				LATEST_VERSION=${WP_VERSION%??}
+			else
+				# otherwise, scan the releases and get the most up to date minor version of the major release
+				local VERSION_ESCAPED=`echo $WP_VERSION | sed 's/\./\\\\./g'`
+				LATEST_VERSION=$(grep -o '"version":"'$VERSION_ESCAPED'[^"]*' $WP_CORE_DIR/wp-latest.json | sed 's/"version":"//' | head -1)
+			fi
+			if [[ -z "$LATEST_VERSION" ]]; then
+				local ARCHIVE_NAME="wordpress-$WP_VERSION"
+			else
+				local ARCHIVE_NAME="wordpress-$LATEST_VERSION"
+			fi
+		else
+			local ARCHIVE_NAME="wordpress-$WP_VERSION"
+		fi
+		download https://wordpress.org/${ARCHIVE_NAME}.tar.gz  $WP_CORE_DIR/wordpress.tar.gz
+		tar --strip-components=1 -zxmf $WP_CORE_DIR/wordpress.tar.gz -C $WP_CORE_DIR
+		rm $WP_CORE_DIR/wordpress.tar.gz
+	fi
+
+	download https://raw.github.com/markoheijnen/wp-mysqli/master/db.php $WP_CORE_DIR/wp-content/db.php
+}
+
+install_test_suite() {
+	# portable in-place argument for both GNU sed and Mac OSX sed
+	if [[ $(uname -s) == 'Darwin' ]]; then
+		local ioption='-i.bak'
+	else
+		local ioption='-i'
+	fi
+
+	# set up testing suite if it doesn't yet exist
+	if [ ! -d $WP_TESTS_DIR ]; then
+		# set up testing suite
+		mkdir -p $WP_TESTS_DIR
+		svn co --quiet https://develop.svn.wordpress.org/${WP_TESTS_TAG}/tests/phpunit/includes/ $WP_TESTS_DIR/includes
+		svn co --quiet https://develop.svn.wordpress.org/${WP_TESTS_TAG}/tests/phpunit/data/ $WP_TESTS_DIR/data
+	fi
+
+	if [ ! -f wp-tests-config.php ]; then
+		download https://develop.svn.wordpress.org/${WP_TESTS_TAG}/wp-tests-config-sample.php "$WP_TESTS_DIR"/wp-tests-config.php
+		# remove all forward slashes in the end
+		WP_CORE_DIR=$(echo $WP_CORE_DIR | sed "s:/\+$::")
+		sed $ioption "s:dirname( __FILE__ ) . '/src/':'$WP_CORE_DIR/':" "$WP_TESTS_DIR"/wp-tests-config.php
+		sed $ioption "s/youremptytestdbnamehere/$DB_NAME/" "$WP_TESTS_DIR"/wp-tests-config.php
+		sed $ioption "s/yourusernamehere/$DB_USER/" "$WP_TESTS_DIR"/wp-tests-config.php
+		sed $ioption "s/yourpasswordhere/$DB_PASS/" "$WP_TESTS_DIR"/wp-tests-config.php
+		sed $ioption "s|localhost|${DB_HOST}|" "$WP_TESTS_DIR"/wp-tests-config.php
+		
+		if [ "$MULTISITE" = "true" ]; then
+			sed $ioption "s:// define( 'WP_TESTS_MULTISITE', true );:define( 'WP_TESTS_MULTISITE', true );:" "$WP_TESTS_DIR"/wp-tests-config.php
+		fi
+	fi
+
+}
+
+install_db() {
+
+	if [ ${SKIP_DB_CREATE} = "true" ]; then
+		return 0
+	fi
+
+	# parse DB_HOST for port or socket references
+	local PARTS=(${DB_HOST//\:/ })
+	local DB_HOSTNAME=${PARTS[0]};
+	local DB_SOCK_OR_PORT=${PARTS[1]};
+	local EXTRA=""
+
+	if ! [ -z $DB_HOSTNAME ] ; then
+		if [ $(echo $DB_SOCK_OR_PORT | grep -e '^[0-9]\{1,\}$') ]; then
+			EXTRA=" --host=$DB_HOSTNAME --port=$DB_SOCK_OR_PORT --protocol=tcp"
+		elif ! [ -z $DB_SOCK_OR_PORT ] ; then
+			EXTRA=" --socket=$DB_SOCK_OR_PORT"
+		elif ! [ -z $DB_HOSTNAME ] ; then
+			EXTRA=" --host=$DB_HOSTNAME --protocol=tcp"
+		fi
+	fi
+
+	# create database
+	mysqladmin create $DB_NAME --user="$DB_USER" --password="$DB_PASS"$EXTRA
+}
+
+install_wp
+install_test_suite
+install_db

composer.json

@@ -32,12 +32,14 @@
     },
     "autoload": {
         "psr-4": {
-            "WPALLSTARS\\PluginStarterTemplate\\": "includes/"
+            "WPALLSTARS\\PluginStarterTemplate\\": "includes/",
+            "WP_Plugin_Starter_Template_For_AI_Coding\\": "includes/"
         }
     },
     "autoload-dev": {
         "classmap": [
-            "includes/Admin/class-admin.php"
+            "includes/Admin/class-admin.php",
+            "tests/phpunit/"
         ]
     },
     "config": {

package.json

@@ -17,6 +17,8 @@
     "test:e2e:multisite": "npm run setup:multisite && sleep 5 && npm run test:multisite:headless",
     "test:playground:single": "cypress run --spec cypress/e2e/playground-single-site.cy.js",
     "test:playground:multisite": "cypress run --spec cypress/e2e/playground-multisite.cy.js",
+    "test:phpunit": "composer test",
+    "test:phpunit:multisite": "WP_MULTISITE=1 composer test",
     "build": "./build.sh",
     "lint:php": "composer run-script phpcs",
     "lint:php:simple": "composer run-script phpcs:simple",

phpunit.xml.dist

@@ -0,0 +1,25 @@
+<?xml version="1.0"?>
+<phpunit
+	bootstrap="tests/phpunit/bootstrap.php"
+	backupGlobals="false"
+	colors="true"
+	convertErrorsToExceptions="true"
+	convertNoticesToExceptions="true"
+	convertWarningsToExceptions="true"
+	>
+	<testsuites>
+		<testsuite name="plugin">
+			<directory prefix="test-" suffix=".php">./tests/phpunit/</directory>
+		</testsuite>
+	</testsuites>
+	<filter>
+		<whitelist>
+			<directory suffix=".php">./includes</directory>
+			<exclude>
+				<directory suffix=".php">./vendor</directory>
+				<directory suffix=".php">./tests</directory>
+				<directory suffix=".php">./node_modules</directory>
+			</exclude>
+		</whitelist>
+	</filter>
+</phpunit>

tests/phpunit/bootstrap.php

@@ -0,0 +1,22 @@
+<?php
+/**
+ * PHPUnit bootstrap file.
+ *
+ * @package WP_Plugin_Starter_Template_For_AI_Coding
+ */
+
+// Composer autoloader must be loaded before WP_PHPUNIT__DIR will be available.
+require_once dirname( dirname( __DIR__ ) ) . '/vendor/autoload.php';
+
+// Give access to tests_add_filter() function.
+require_once getenv( 'WP_PHPUNIT__DIR' ) . '/includes/functions.php';
+
+/**
+ * Manually load the plugin being tested.
+ */
+function _manually_load_plugin() {
+	require dirname( dirname( __DIR__ ) ) . '/plugin-toggle.php';
+}
+
+// Start up the WP testing environment.
+require getenv( 'WP_PHPUNIT__DIR' ) . '/includes/bootstrap.php';

tests/phpunit/test-multisite.php

@@ -0,0 +1,56 @@
+<?php
+/**
+ * Class MultisiteTest
+ *
+ * @package WP_Plugin_Starter_Template_For_AI_Coding
+ */
+
+/**
+ * Sample test case for the Multisite class.
+ */
+class MultisiteTest extends WP_UnitTestCase {
+
+	/**
+	 * Test instance creation.
+	 */
+	public function test_instance() {
+		$multisite = new WP_Plugin_Starter_Template_For_AI_Coding\Multisite\Multisite();
+		$this->assertInstanceOf( 'WP_Plugin_Starter_Template_For_AI_Coding\Multisite\Multisite', $multisite );
+	}
+
+	/**
+	 * Test is_multisite_compatible method.
+	 */
+	public function test_is_multisite_compatible() {
+		$multisite = new WP_Plugin_Starter_Template_For_AI_Coding\Multisite\Multisite();
+		$this->assertTrue( $multisite->is_multisite_compatible() );
+	}
+
+	/**
+	 * Test get_network_sites method.
+	 */
+	public function test_get_network_sites() {
+		$multisite = new WP_Plugin_Starter_Template_For_AI_Coding\Multisite\Multisite();
+		
+		// Mock the get_sites function if we're not in a multisite environment.
+		if ( ! function_exists( 'get_sites' ) ) {
+			$this->assertEquals( array(), $multisite->get_network_sites() );
+		} else {
+			$sites = $multisite->get_network_sites();
+			$this->assertIsArray( $sites );
+		}
+	}
+
+	/**
+	 * Test initialize_hooks method.
+	 */
+	public function test_initialize_hooks() {
+		$multisite = new WP_Plugin_Starter_Template_For_AI_Coding\Multisite\Multisite();
+		
+		// Call the method.
+		$multisite->initialize_hooks();
+		
+		// Check if the action was added.
+		$this->assertEquals( 10, has_action( 'network_admin_menu', array( $multisite, 'add_network_menu' ) ) );
+	}
+}