WordPress Testing & QA

Testing strategies for WordPress plugins and themes covering unit tests, integration tests, E2E tests, static analysis, and CI/CD pipelines.

Test Types

Unit Tests (WP_Mock)

Test isolated classes/functions without WordPress loaded. Fast execution, no database.

php

use WP_Mock\Tools\TestCase;

class MyPluginTest extends TestCase {
    public function test_format_output() {
        WP_Mock::userFunction( 'esc_html' )
            ->once()
            ->with( 'test' )
            ->andReturn( 'test' );

        $result = my_format_function( 'test' );
        $this->assertEquals( 'test', $result );
    }
}

Integration Tests (WP_UnitTestCase)

Test against actual WordPress with database. Slower but comprehensive.

bash

# Install test suite
composer require --dev phpunit/phpunit yoast/phpunit-polyfills
bash bin/install-wp-tests.sh wordpress_test root password localhost latest

php

class MyPlugin_Integration_Test extends WP_UnitTestCase {
    public function test_post_creation() {
        $post_id = $this->factory->post->create( [
            'post_title' => 'Test Post',
        ] );

        $this->assertGreaterThan( 0, $post_id );
    }

    public function test_rest_endpoint() {
        $request = new WP_REST_Request( 'GET', '/myplugin/v1/items' );
        $response = rest_get_server()->dispatch( $request );

        $this->assertEquals( 200, $response->get_status() );
    }
}

E2E Tests (Playwright)

javascript

import { test, expect } from '@wordpress/e2e-test-utils-playwright';

test( 'block renders in editor', async ( { admin, editor } ) => {
    await admin.createNewPost();
    await editor.insertBlock( { name: 'my-plugin/my-block' } );
    await expect( editor.canvas.locator( '.wp-block-my-block' ) ).toBeVisible();
} );

phpunit.xml

xml

<?xml version="1.0"?>
<phpunit
    bootstrap="tests/bootstrap.php"
    backupGlobals="false"
    colors="true"
>
    <testsuites>
        <testsuite name="unit">
            <directory suffix="Test.php">tests/unit</directory>
        </testsuite>
        <testsuite name="integration">
            <directory suffix="Test.php">tests/integration</directory>
        </testsuite>
    </testsuites>
</phpunit>

Static Analysis

PHPCS (WordPress Coding Standards)

json

{
    "require-dev": {
        "wp-coding-standards/wpcs": "^3.0",
        "phpcompatibility/phpcompatibility-wp": "*",
        "dealerdirect/phpcodesniffer-composer-installer": "^1.0"
    }
}

xml

<!-- phpcs.xml -->
<ruleset name="My Plugin">
    <rule ref="WordPress"/>
    <rule ref="WordPress-Extra"/>
    <rule ref="WordPress-Docs"/>
    <rule ref="PHPCompatibilityWP"/>
    <config name="testVersion" value="8.2-"/>
    <config name="minimum_wp_version" value="6.9"/>
    <file>./includes</file>
    <file>./my-plugin.php</file>
</ruleset>

PHPStan

neon

# phpstan.neon
includes:
    - vendor/szepeviktor/phpstan-wordpress/extension.neon
parameters:
    level: 6
    paths:
        - includes/
        - my-plugin.php

CI/CD Workflow

yaml

# .github/workflows/ci.yml
jobs:
  test:
    strategy:
      matrix:
        php: ['8.2', '8.3', '8.4']
        wp: ['6.7', '6.8', '6.9', 'trunk']
    steps:
      - uses: shivammathur/setup-php@v2
        with:
          php-version: ${{ matrix.php }}
      - run: composer install --no-progress
      - run: bash bin/install-wp-tests.sh wordpress_test root '' 127.0.0.1 ${{ matrix.wp }}
      - run: vendor/bin/phpunit

  lint:
    steps:
      - run: vendor/bin/phpcs
      - run: vendor/bin/phpstan analyse

Test Checklist

• Unit tests for business logic (WP_Mock)
• Integration tests for WordPress interactions (WP_UnitTestCase)
• PHPCS with WordPress-Extra ruleset
• PHPStan level 6+
• PHP compatibility check (8.2+)
• E2E tests for blocks (Playwright)
• Multisite compatibility test
• i18n validation (missing text domains)
• Accessibility linting (axe-core)