REST API: Improve formatting of failed validation errors.

If a validation_callback returns a WP_Error it should give the same response format as if it returned `false`. This makes programmatically reading the validation errors better.

Props bradyvercher for initial patch.
Fixes #35028.


git-svn-id: https://develop.svn.wordpress.org/trunk@35890 602fd350-edb4-49c9-b593-d223f7449a82

.gitignore

@@ -1,5 +1,5 @@
 # gitignore file for WordPress Core
-
+.svn
 # Configuration files with possibly sensitive information
 wp-config.php
 wp-tests-config.php

src/wp-includes/rest-api/class-wp-rest-request.php

@@ -851,13 +851,13 @@ class WP_REST_Request implements ArrayAccess {
 				}
 
 				if ( is_wp_error( $valid_check ) ) {
-					$invalid_params[] = sprintf( '%s (%s)', $key, $valid_check->get_error_message() );
+					$invalid_params[ $key ] = $valid_check->get_error_message();
 				}
 			}
 		}
 
 		if ( $invalid_params ) {
-			return new WP_Error( 'rest_invalid_param', sprintf( __( 'Invalid parameter(s): %s' ), implode( ', ', $invalid_params ) ), array( 'status' => 400, 'params' => $invalid_params ) );
+			return new WP_Error( 'rest_invalid_param', sprintf( __( 'Invalid parameter(s): %s' ), implode( ', ', array_keys( $invalid_params ) ) ), array( 'status' => 400, 'params' => $invalid_params ) );
 		}
 
 		return true;

tests/phpunit/tests/rest-api/rest-request.php

@@ -391,4 +391,33 @@ class Tests_REST_Request extends WP_UnitTestCase {
 		$this->assertArrayHasKey( 'someinteger', $data['params'] );
 		$this->assertArrayHasKey( 'someotherinteger', $data['params'] );
 	}
+
+	public function test_invalid_params_error_response_format() {
+		$this->request->set_url_params( array(
+			'someinteger' => '123',
+			'someotherparams' => '123',
+		));
+
+		$this->request->set_attributes( array(
+			'args' => array(
+				'someinteger' => array(
+					'validate_callback' => '__return_false',
+				),
+				'someotherparams' => array(
+					'validate_callback' => array( $this, '_return_wp_error_on_validate_callback' ),
+				),
+			),
+		));
+
+		$valid = $this->request->has_valid_params();
+		$this->assertWPError( $valid );
+		$error_data = $valid->get_error_data();
+
+		$this->assertEquals( array( 'someinteger', 'someotherparams' ), array_keys( $error_data['params'] ) );
+		$this->assertEquals( 'This is not valid!', $error_data['params']['someotherparams'] );
+	}
+
+	public function _return_wp_error_on_validate_callback() {
+		return new WP_Error( 'some-error', 'This is not valid!' );
+	}
 }