test: adding phpunit tests

.github/workflows/test-php.yml

@@ -60,3 +60,49 @@ jobs:
               run: composer install --prefer-dist --no-progress --no-suggest
             - name: PHPStan Static Analysis
               run: composer phpstan
+
+    phpunit:
+        name: PHPUnit
+        runs-on: ubuntu-latest
+        if: github.event.pull_request.draft == false && github.event.pull_request.head.repo.full_name == github.event.pull_request.base.repo.full_name
+        services:
+          mysql:
+            image: mysql:5.7
+            env:
+              MYSQL_ROOT_PASSWORD: root
+            ports:
+              - 3306/tcp
+            options: --health-cmd="mysqladmin ping" --health-interval=10s --health-timeout=5s --health-retries=3
+        steps:
+            - name: Setup PHP version
+              uses: shivammathur/setup-php@v2
+              with:
+                  php-version: '8.1'
+                  extensions: simplexml, mysql
+                  tools: phpunit-polyfills
+            - name: Checkout source code
+              uses: actions/checkout@v2
+            - name: Get Composer Cache Directory
+              id: composer-cache
+              run: |
+                  echo "::set-output name=dir::$(composer config cache-files-dir)"
+            - name: Setup Composer cache
+              uses: actions/cache@v1
+              with:
+                  path: ${{ steps.composer-cache.outputs.dir }}
+                  key: ${{ runner.os }}-composer-${{ hashFiles('**/composer.lock') }}
+                  restore-keys: |
+                      ${{ runner.os }}-composer-
+            - name: Install Subversion
+              run: sudo apt-get update && sudo apt-get install -y subversion
+            - name: Install composer
+              run: composer install --prefer-dist --no-progress --no-suggest
+            - name: Install npm
+              run: npm ci
+            - name: Run build
+              run: npm run build
+            - name: Install WordPress Test Suite
+              run: |
+                bash bin/install-wp-tests.sh wordpress_test root root 127.0.0.1:${{ job.services.mysql.ports['3306'] }}
+            - name: PHPUnit tests
+              run: composer run-script phpunit

bin/install-wp-tests.sh

@@ -0,0 +1,152 @@
+#!/usr/bin/env bash
+
+if [ $# -lt 3 ]; then
+	echo "usage: $0 <db-name> <db-user> <db-pass> [db-host] [wp-version] [skip-database-creation]"
+	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}
+
+TMPDIR=${TMPDIR-/tmp}
+TMPDIR=$(echo $TMPDIR | sed -e "s/\/$//")
+WP_TESTS_DIR=${WP_TESTS_DIR-$TMPDIR/wordpress-tests-lib}
+WP_CORE_DIR=${WP_CORE_DIR-$TMPDIR/wordpress/}
+
+download() {
+    if [ `which curl` ]; then
+        curl -s "$1" > "$2";
+    elif [ `which wget` ]; then
+        wget -nv -O "$2" "$1"
+    fi
+}
+
+if [[ $WP_VERSION =~ ^[0-9]+\.[0-9]+$ ]]; 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 $TMPDIR/wordpress-nightly
+		download https://wordpress.org/nightly-builds/wordpress-latest.zip  $TMPDIR/wordpress-nightly/wordpress-nightly.zip
+		unzip -q $TMPDIR/wordpress-nightly/wordpress-nightly.zip -d $TMPDIR/wordpress-nightly/
+		mv $TMPDIR/wordpress-nightly/wordpress/* $WP_CORE_DIR
+	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/ $TMPDIR/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'[^"]*' $TMPDIR/wp-latest.json | sed 's/"version":"//' | head -1)
+			fi
+			if [[ -z "$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  $TMPDIR/wordpress.tar.gz
+		tar --strip-components=1 -zxmf $TMPDIR/wordpress.tar.gz -C $WP_CORE_DIR
+	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
+	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

@@ -25,14 +25,17 @@
 	"scripts": {
 		"lint": "phpcs --standard=phpcs.xml",
 		"format": "phpcbf --standard=phpcs.xml",
-		"phpstan": "phpstan analyse --memory-limit 2G"
+		"phpstan": "phpstan analyse --memory-limit 2G",
+		"phpunit": "phpunit"
 	},
 	"require-dev": {
 		"phpstan/phpstan": "^1.10",
 		"szepeviktor/phpstan-wordpress": "^1.3",
 		"wp-coding-standards/wpcs": "^3.0",
 		"automattic/vipwpcs": "^3.0",
-		"phpcompatibility/php-compatibility": "^9.3"
+		"phpcompatibility/php-compatibility": "^9.3",
+        "phpunit/phpunit": "^9.6",
+        "yoast/phpunit-polyfills": "^2.0"
 	},
 	"config": {
 		"platform": {