Refactor handle_upload() rather than change import_error() visibility.

plugins/woocommerce/includes/admin/importers/class-wc-tax-rate-importer.php

@@ -50,6 +50,13 @@ class WC_Tax_Rate_Importer extends WP_Importer {
 	 */
 	public $delimiter;
 
+	/**
+	 * Error message for import.
+	 *
+	 * @var string
+	 */
+	public $import_error_message;
+
 	/**
 	 * Constructor.
 	 */
@@ -89,6 +96,8 @@ class WC_Tax_Rate_Importer extends WP_Importer {
 					add_filter( 'http_request_timeout', array( $this, 'bump_request_timeout' ) );
 
 					$this->import( $file );
+				} else {
+					$this->import_error( $this->import_error_message );
 				}
 				break;
 		}
@@ -193,6 +202,15 @@ class WC_Tax_Rate_Importer extends WP_Importer {
 		do_action( 'import_end' );
 	}
 
+	/**
+	 * Set the import error message.
+	 *
+	 * @param string $message Error message.
+	 */
+	protected function set_import_error_message( $message ) {
+		$this->import_error_message = $message;
+	}
+
 	/**
 	 * Handles the CSV upload and initial parsing of the file to prepare for.
 	 * displaying author import options.
@@ -206,14 +224,18 @@ class WC_Tax_Rate_Importer extends WP_Importer {
 			$file = wp_import_handle_upload();
 
 			if ( isset( $file['error'] ) ) {
-				$this->import_error( $file['error'] );
+				$this->set_import_error_message( $file['error'] );
+
+				return false;
 			}
 
 			if ( ! wc_is_file_valid_csv( $file['file'], false ) ) {
 				// Remove file if not valid.
 				wp_delete_attachment( $file['id'], true );
 
-				$this->import_error( __( 'Invalid file type. The importer supports CSV and TXT file formats.', 'woocommerce' ) );
+				$this->set_import_error_message( __( 'Invalid file type. The importer supports CSV and TXT file formats.', 'woocommerce' ) );
+
+				return false;
 			}
 
 			$this->id = absint( $file['id'] );
@@ -222,12 +244,14 @@ class WC_Tax_Rate_Importer extends WP_Importer {
 			file_exists( ABSPATH . $file_url )
 		) {
 			if ( ! wc_is_file_valid_csv( ABSPATH . $file_url ) ) {
-				$this->import_error( __( 'Invalid file type. The importer supports CSV and TXT file formats.', 'woocommerce' ) );
+				$this->set_import_error_message( __( 'Invalid file type. The importer supports CSV and TXT file formats.', 'woocommerce' ) );
+
+				return false;
 			}
 
 			$this->file_url = esc_attr( $file_url );
 		} else {
-			$this->import_error();
+			return false;
 		}
 
 		return true;
@@ -322,7 +346,7 @@ class WC_Tax_Rate_Importer extends WP_Importer {
 	 *
 	 * @param  string $message Error message.
 	 */
-	public function import_error( $message = '' ) {
+	private function import_error( $message = '' ) {
 		echo '<p><strong>' . esc_html__( 'Sorry, there has been an error.', 'woocommerce' ) . '</strong><br />';
 		if ( $message ) {
 			echo esc_html( $message );

plugins/woocommerce/tests/legacy/unit-tests/importer/tax.php

@@ -44,18 +44,11 @@ class WC_Tests_Tax_CSV_Importer extends WC_Unit_Test_Case {
 	 * Test that directory traversal is prevented.
 	 */
 	public function test_import_path_traversal() {
-		$importer =
+		$importer = new WC_Tax_Rate_Importer();
-			$this->getMockBuilder( WC_Tax_Rate_Importer::class )
-				->setMethods( array( 'import_error' ) )
-				->getMock();
-
-		$importer
-			->expects( $this->once() )
-			->method( 'import_error' )
-			->willReturn( false );
 
 		$_POST['file_url'] = '../sample_tax_rates.csv';
 
-		$importer->handle_upload();
+		$this->assertFalse( $importer->handle_upload() );
+		$this->assertEquals( '', $importer->import_error_message );
 	}
 }