Use GitHub actions.

.github/workflows/integration-and-unit-tests.yml

@@ -0,0 +1,74 @@
+name: Integration and Unit Tests
+
+on:
+  push:
+    branches: master
+    paths:
+      - '**.php'
+      - 'phpunit.xml'
+      - 'composer.json'
+      - '**.yml'
+  pull_request:
+    branches: master
+    paths:
+      - '**.php'
+      - 'phpunit.xml'
+      - 'composer.json'
+      - '**.yml'
+  workflow_dispatch:
+
+jobs:
+  testing:
+    name: WP ${{ matrix.wordpress-version }} + PHP ${{ matrix.php-version }} + MS ${{ matrix.is-multisite }} + Allowed to fail ${{ matrix.allow-failure }}
+
+    runs-on: ubuntu-latest
+
+    services:
+      mysql:
+        image: mariadb:latest
+        ports:
+          - '3306:3306'
+        env:
+          MYSQL_ROOT_PASSWORD: wordpress
+          MARIADB_INITDB_SKIP_TZINFO: 1
+          MYSQL_USER: wordpress
+          MYSQL_PASSWORD: wordpress
+          MYSQL_DATABASE: wordpress_test
+
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - wordpress-version: '5.2.x'
+            php-version: '7.2'
+            is-multisite: 0
+            allow-failure: false
+          - wordpress-version: 'latest'
+            php-version: '7.0'
+            is-multisite: 0
+            allow-failure: false
+          - wordpress-version: 'latest'
+            php-version: '8.2'
+            is-multisite: 0
+            allow-failure: false
+          - wordpress-version: 'nightly'
+            php-version: '7.0'
+            is-multisite: 0
+            allow-failure: true
+          - wordpress-version: 'nightly'
+            php-version: '8.3'
+            is-multisite: 0
+            allow-failure: true
+
+    env:
+      WP_MULTISITE: ${{ matrix.is-multisite }}
+
+    steps:
+      - name: Check out the source code
+        uses: actions/checkout@v3
+
+      - name: Run PHPUnit tests
+        uses: polylang/actions/phpunit@main
+        with:
+          php-version: ${{ matrix.php-version }}
+          wordpress-version: ${{ matrix.wordpress-version }}

.github/workflows/static-analysis.yml

@@ -0,0 +1,21 @@
+name: Static Analysis
+
+on:
+  push:
+    branches: master
+  pull_request:
+    branches: master
+  workflow_dispatch:
+
+jobs:
+  testing:
+    name: PHPCS and PHPStan
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: Check out the source code
+      uses: actions/checkout@v3
+
+    - name: Run PHPCS and PHPStan tests
+      uses: polylang/actions/static-analysis@main

tests/phpunit/bootstrap.php

@@ -1,7 +1,7 @@
 <?php
 
 $_root_dir  = dirname( __DIR__, 2 );
-$_tests_dir = $_root_dir . '/tmp/wordpress-tests-lib';
+$_tests_dir = ! empty( getenv( 'WP_TESTS_DIR' ) ) ? getenv( 'WP_TESTS_DIR' ) : $_root_dir . '/tmp/wordpress-tests-lib';
 require_once $_tests_dir . '/includes/functions.php';
 
 require_once $_root_dir . '/vendor/autoload.php';