Prevent orders being placed when no shipping options are available (#…

…46026)

* Prevent orders being placed with invalid shipping options

* Add changelog

* Add shipping_disable_flat_rate fixture function

* Test checking out with no valid shipping methods selected

* Update tests to add a default shipping method

* Update test_checkout_invalid_shipping_method to disable method

* If shipping methods is null, return an array with an empty string inside

* Replace WC session in tests that rely on setting cookies

* Add MockSessionHandler to handle test cases using cookies

* Add docblock comment

* Expect shipping validation to fail if chosen methods are null

* Add shipping method before testing validate_selected_shipping_methods

* Update MockSessionHandler to handle caching

* Show error when test fails

* Default the chosen shipping methods to an empty array if not set

* Split checks for needs_shipping and valid shipping apart

* Remove unnecessary session set and total calculation

* Fix lint errors

* Init session in each test

* Reimplement required methods (those that are private or use cookies)

* Update phpcs ignore comment to be inline

* Prevent error when accessing unset variable in mock cache

* Fix lint error

plugins/woocommerce/tests/php/src/Blocks/Helpers/FixtureData.php

@@ -321,6 +321,26 @@ public function shipping_add_flat_rate( $cost = 10 ) {
 		WC()->shipping()->load_shipping_methods();
 	}
 
+	/**
+	 * Disables the flat rate method.
+	 *
+	 * @param float $cost Optional. Cost of flat rate method.
+	 */
+	public function shipping_disable_flat_rate( $cost = 10 ) {
+		$flat_rate_settings = array(
+			'enabled'      => 'no',
+			'title'        => 'Flat rate',
+			'availability' => 'all',
+			'countries'    => '',
+			'tax_status'   => 'taxable',
+			'cost'         => $cost,
+		);
+		update_option( 'woocommerce_flat_rate_settings', $flat_rate_settings );
+		update_option( 'woocommerce_flat_rate', array() );
+		\WC_Cache_Helper::get_transient_version( 'shipping', true );
+		WC()->shipping()->load_shipping_methods();
+	}
+
 	/**
 	 * Enable bacs payment method.
 	 */

plugins/woocommerce/tests/php/src/Blocks/StoreApi/Routes/Checkout.php

@@ -324,8 +324,6 @@ public function test_not_passing_extensions_data() {
 	 * Check that accounts are created on request.
 	 */
 	public function test_checkout_create_account() {
-		$enable_guest_checkout = get_option( 'woocommerce_enable_guest_checkout' );
-		$enable_signup_login   = get_option( 'woocommerce_enable_signup_and_login_from_checkout' );
 		// We need to replace the WC_Session with a mock because this test relies on cookies being set which
 		// is not easy with PHPUnit. This is a simpler approach.
 		$old_session  = WC()->session;
@@ -391,16 +389,12 @@ public function test_checkout_create_account() {
 		update_option( 'woocommerce_enable_signup_and_login_from_checkout', $enable_signup_login );
 		// Return WC_Session to original state.
 		WC()->session = $old_session;
-		update_option( 'woocommerce_enable_guest_checkout', $enable_guest_checkout );
-		update_option( 'woocommerce_enable_signup_and_login_from_checkout', $enable_signup_login );
 	}
 
 	/**
 	 * Test account creation options.
 	 */
 	public function test_checkout_do_not_create_account() {
-		$enable_guest_checkout = get_option( 'woocommerce_enable_guest_checkout' );
-		$enable_signup_login   = get_option( 'woocommerce_enable_signup_and_login_from_checkout' );
 		// We need to replace the WC_Session with a mock because this test relies on cookies being set which
 		// is not easy with PHPUnit. This is a simpler approach.
 		$old_session  = WC()->session;
@@ -463,16 +457,12 @@ public function test_checkout_do_not_create_account() {
 		update_option( 'woocommerce_enable_signup_and_login_from_checkout', $enable_signup_login );
 		// Return WC_Session to original state.
 		WC()->session = $old_session;
-		update_option( 'woocommerce_enable_guest_checkout', $enable_guest_checkout );
-		update_option( 'woocommerce_enable_signup_and_login_from_checkout', $enable_signup_login );
 	}
 
 	/**
 	 * Test account creation options.
 	 */
 	public function test_checkout_force_create_account() {
-		$enable_guest_checkout = get_option( 'woocommerce_enable_guest_checkout' );
-		$enable_signup_login   = get_option( 'woocommerce_enable_signup_and_login_from_checkout' );
 		// We need to replace the WC_Session with a mock because this test relies on cookies being set which
 		// is not easy with PHPUnit. This is a simpler approach.
 		$old_session  = WC()->session;
@@ -537,8 +527,6 @@ public function test_checkout_force_create_account() {
 		update_option( 'woocommerce_enable_signup_and_login_from_checkout', $enable_signup_login );
 		// Return WC_Session to original state.
 		WC()->session = $old_session;
-		update_option( 'woocommerce_enable_guest_checkout', $enable_guest_checkout );
-		update_option( 'woocommerce_enable_signup_and_login_from_checkout', $enable_signup_login );
 	}
 
 	/**