[WOOTAX-299] Fix - Don't register the continents fallback on unrelated REST requests

changelog.txt

@@ -15,6 +15,7 @@
 * Tweak - Centralize TaxJar address handling in an internal value object. No change to tax calculation.
 * Tweak - Store tax rate rows against the postcode the rate was quoted for when the address postcode holds more than one comma-separated value.
 * Tweak - Reduce redundant TaxJar API calls by matching cached tax responses across the cart and order paths and ignoring irrelevant formatting differences.
+* Tweak - Stop registering a redundant copy of the continents REST endpoint on requests that cannot reach it.
 
 = 3.6.11 - 2026-08-05 =
 * Fix   - Prevent a fatal error during cart and checkout tax calculation when TaxJar returns an incomplete tax response.

readme.txt

@@ -85,6 +85,7 @@ This plugin relies on the following external services:
 * Tweak - Centralize TaxJar address handling in an internal value object. No change to tax calculation.
 * Tweak - Store tax rate rows against the postcode the rate was quoted for when the address postcode holds more than one comma-separated value.
 * Tweak - Reduce redundant TaxJar API calls by matching cached tax responses across the cart and order paths and ignoring irrelevant formatting differences.
+* Tweak - Stop registering a redundant copy of the continents REST endpoint on requests that cannot reach it.
 
 = 3.6.11 - 2026-08-05 =
 * Fix   - Prevent a fatal error during cart and checkout tax calculation when TaxJar returns an incomplete tax response.

tests/php/test-woocommerce-connect-client.php

@@ -90,6 +90,83 @@ public function test_class_exists() {
 		$this->assertTrue( class_exists( 'WC_Connect_Loader' ) );
 	}
 
+	/**
+	 * The bundled wc-api-dev copy of /wc/v3/data/continents is a fallback for WooCommerce versions
+	 * that predate the endpoint. Core has shipped it since WC 3.5, so on any supported WooCommerce
+	 * the fallback must stay dormant.
+	 *
+	 * This is the regression guard for the lazy-namespace interaction: since WC 9.2 core skips
+	 * registering the whole wc/v3 namespace on requests aimed at another namespace, so the route
+	 * table alone cannot tell us whether core provides the endpoint.
+	 *
+	 * Asserted against the route table rather than against class-load state: whether the bundled
+	 * class has been required is process-global and outlives whichever test loaded it, so it cannot
+	 * carry this contract under an arbitrary execution order.
+	 *
+	 * @covers WC_Connect_Loader::wc_api_dev_init
+	 */
+	public function test_wc_api_dev_init_defers_to_core_continents_controller() {
+		global $wp, $wp_rest_server;
+
+		if ( ! function_exists( 'wc_rest_should_load_namespace' ) ) {
+			$this->markTestSkipped( 'This WooCommerce does not register REST namespaces lazily.' );
+		}
+
+		$this->assertTrue(
+			class_exists( 'WC_REST_Data_Continents_Controller' ),
+			'WooCommerce core is expected to provide WC_REST_Data_Continents_Controller.'
+		);
+
+		$original_server = $wp_rest_server;
+		$original_route  = isset( $wp->query_vars['rest_route'] ) ? $wp->query_vars['rest_route'] : null;
+
+		// Reproduce a Store API request: core then skips the whole wc/v3 namespace, so
+		// /wc/v3/data/continents is missing from the route table even though core provides it.
+		$wp->query_vars['rest_route'] = '/wc/store/v1/cart';
+		$wp_rest_server               = null;
+
+		try {
+			$this->assertArrayNotHasKey(
+				'/wc/v3/data/continents',
+				rest_get_server()->get_routes(),
+				'Expected WooCommerce to defer the wc/v3 namespace on a wc/store request.'
+			);
+
+			$this->mockLoader()->wc_api_dev_init();
+
+			$this->assertArrayNotHasKey(
+				'/wc/v3/data/continents',
+				rest_get_server()->get_routes(),
+				'The bundled wc-api-dev continents controller must not register a route when WooCommerce core provides its own.'
+			);
+		} finally {
+			$wp_rest_server = $original_server;
+
+			if ( null === $original_route ) {
+				unset( $wp->query_vars['rest_route'] );
+			} else {
+				$wp->query_vars['rest_route'] = $original_route;
+			}
+		}
+	}
+
+	/**
+	 * Pins the fix shipped in 2.5.1: the bundled controller used to call parent::__construct(),
+	 * but no class in its ancestry (WC_REST_Dev_Data_Controller, WC_REST_Controller,
+	 * WP_REST_Controller) declares a constructor, so that call raised
+	 * "Uncaught Error: Cannot call constructor" every time the fallback branch was reached.
+	 */
+	public function test_bundled_continents_controller_is_constructible() {
+
+		require_once __DIR__ . '/../../classes/class-wc-connect-continents.php';
+		require_once __DIR__ . '/../../classes/wc-api-dev/class-wc-rest-dev-data-controller.php';
+		require_once __DIR__ . '/../../classes/wc-api-dev/class-wc-rest-dev-data-continents-controller.php';
+
+		$controller = new WC_REST_Dev_Data_Continents_Controller();
+
+		$this->assertInstanceOf( 'WC_REST_Dev_Data_Continents_Controller', $controller );
+	}
+
 	/**
 	 * @covers WC_Connect_Loader::__construct
 	 */

woocommerce-services.php

@@ -1298,9 +1298,27 @@ public function rest_api_init() {
 		 * Delete this when the "v3" REST API is included in all the WC versions we support.
 		 */
 		public function wc_api_dev_init() {
+			/*
+			 * Ask whether WooCommerce *provides* the endpoint, not whether it happens to be in the
+			 * route table for this request.
+			 *
+			 * Since WooCommerce 9.2 the wc/v3 namespace is registered lazily: Server::get_rest_namespaces()
+			 * consults wc_rest_should_load_namespace(), which returns false whenever the current request
+			 * targets a different known namespace (wc/store, wc-analytics, wc-admin, ...). On all of those
+			 * requests /wc/v3/data/continents is legitimately absent even though core supplies it, so
+			 * registering our bundled copy there is dead work: the request cannot dispatch to the route,
+			 * and route registrations do not outlive the request that made them.
+			 */
+			if ( class_exists( 'WC_REST_Data_Continents_Controller' ) ) {
+				return;
+			}
+
 			$rest_server     = rest_get_server();
 			$existing_routes = $rest_server->get_routes();
 			if ( ! isset( $existing_routes['/wc/v3/data/continents'] ) ) {
+				// The controller below constructs WC_Connect_Continents; keep the fallback self-contained
+				// rather than relying on load_dependencies() having already required it.
+				require_once __DIR__ . '/classes/class-wc-connect-continents.php';
 				require_once __DIR__ . '/classes/wc-api-dev/class-wc-rest-dev-data-controller.php';
 				require_once __DIR__ . '/classes/wc-api-dev/class-wc-rest-dev-data-continents-controller.php';
 				$continents = new WC_REST_Dev_Data_Continents_Controller();