WooCommerce Testing

Before writing code

Fetch live docs:

1. Web-search site:developer.woocommerce.com testing for WooCommerce testing guide
2. Web-search site:developer.wordpress.org plugins testing for WordPress Plugin testing handbook
3. Web-search woocommerce e2e testing playwright for E2E patterns

Test Types

Unit Tests

Isolated class/function testing:

• No WordPress/WooCommerce bootstrap
• Mock all dependencies
• Fast execution
• Test pure business logic

Integration Tests

Tests with WordPress + WooCommerce loaded:

• Extend WC_Unit_Test_Case (which extends WP_UnitTestCase)
• Full WordPress database (using transactions for rollback)
• Access to all WooCommerce APIs and hooks
• Test plugin integration with WooCommerce

E2E (End-to-End) Tests

Browser-based tests with Playwright:

• Test complete user flows (add to cart, checkout, payment)
• WooCommerce provides Playwright utilities
• Run against a real WordPress + WooCommerce instance

Setting Up PHPUnit Tests

Scaffold with WP-CLI

wp scaffold plugin-tests my-plugin creates:

• tests/bootstrap.php — test bootstrap
• tests/test-sample.php — sample test
• phpunit.xml.dist — PHPUnit configuration
• bin/install-wp-tests.sh — install WordPress test suite

WooCommerce Test Bootstrap

After WordPress test bootstrap, load WooCommerce and your plugin:

// In tests/bootstrap.php
require_once dirname( __DIR__ ) . '/vendor/woocommerce/woocommerce/tests/legacy/bootstrap.php';
// Or manually: activate WooCommerce, then your plugin

WC_Unit_Test_Case

Base class providing:

• Transaction-based test isolation (each test rolled back)
• WooCommerce helper methods
• Proper environment setup/teardown

Test Helpers

WC_Helper_Product

Factory for creating test products:

• WC_Helper_Product::create_simple_product() — simple product with defaults
• WC_Helper_Product::create_variation_product() — variable + variations
• WC_Helper_Product::create_grouped_product() — grouped product
• WC_Helper_Product::create_external_product() — external/affiliate

WC_Helper_Order

Factory for creating test orders:

• WC_Helper_Order::create_order( $customer_id ) — order with line items
• Configurable status, products, addresses

WC_Helper_Customer

• WC_Helper_Customer::create_customer() — customer with address
• WC_Helper_Customer::create_mock_customer() — mock customer object

WC_Helper_Shipping

• WC_Helper_Shipping::create_simple_flat_rate() — flat rate shipping zone
• Set up shipping zones and methods for checkout tests

WC_Helper_Coupon

• WC_Helper_Coupon::create_coupon() — discount coupon with configurable type/amount

Testing Patterns

Testing Hooks

Verify your hooks fire correctly:

• Check that a callback is registered: has_action( 'hook_name', [ $instance, 'method' ] )
• Test the callback's effect by triggering the hook
• Use did_action( 'hook_name' ) to verify an action fired

Testing CRUD Operations

1. Create an object (product, order, etc.)
2. Perform operations (update, delete, query)
3. Assert expected state
4. Cleanup happens automatically via transaction rollback

Testing REST API Endpoints

Use WP_REST_Server to dispatch requests:

• $request = new WP_REST_Request( 'GET', '/wc/v3/products' )
• $response = rest_get_server()->dispatch( $request )
• Assert status code, response data, headers

Testing Payment Gateways

• Create order, set payment method
• Call process_payment() with test credentials
• Assert order status changes
• Test refund flow

Mocking

• Use PHPUnit mocks: $this->createMock( ClassName::class )
• Mock HTTP requests: add_filter( 'pre_http_request', $mock_response )
• WooCommerce provides WC_Mock_Payment_Gateway and similar mocks

E2E Testing with Playwright

Setup

WooCommerce uses @woocommerce/e2e-utils and Playwright:

• Configure in playwright.config.js
• Tests in tests/e2e/specs/
• Page objects for common pages (shop, cart, checkout, my-account)

Common E2E Flows

• Add product to cart → verify cart → proceed to checkout → complete order
• Customer registration and login
• Admin: create product, manage orders, configure settings
• Payment gateway integration testing

Best Practices

• Use WC_Unit_Test_Case for integration tests
• Use WooCommerce helper classes (WC_Helper_Product, etc.) for test fixtures
• Test with HPOS enabled and disabled
• Test with both classic and block checkout
• Mock external API calls (payment processors, shipping carriers)
• Use @group annotations for test organization
• Clean up created data (helpers handle this via transaction rollback)
• Run tests in CI with WordPress test suite

Fetch the WooCommerce testing documentation and WordPress testing handbook for exact helper methods, bootstrap setup, and E2E configuration before implementing.