From 81ffd2492c0092ef49135c9f8e5c661dd8e96947 Mon Sep 17 00:00:00 2001
From: Ryan McCue <me@ryanmccue.info>
Date: Tue, 17 Nov 2015 04:12:26 +0000
Subject: [PATCH] REST API: Optimise for singular error instances.

Previously, the API returned a list of errors, as WP_Error can hold multiple
error codes internally. This isn't a particularly common use case, and it
makes handling errors on the client side more complex than it needs to be.

Fixes #34551.

Built from https://develop.svn.wordpress.org/trunk@35653


git-svn-id: http://core.svn.wordpress.org/trunk@35617 1a063a9b-81f0-0310-95a4-ce76da25c4cd
---
 wp-includes/rest-api/class-wp-rest-server.php | 13 ++++++++++---
 wp-includes/version.php                       |  2 +-
 2 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/wp-includes/rest-api/class-wp-rest-server.php b/wp-includes/rest-api/class-wp-rest-server.php
index 05e10a9399..b094634985 100644
--- a/wp-includes/rest-api/class-wp-rest-server.php
+++ b/wp-includes/rest-api/class-wp-rest-server.php
@@ -162,14 +162,21 @@ class WP_REST_Server {
 			$status = 500;
 		}
 
-		$data = array();
+		$errors = array();
 
 		foreach ( (array) $error->errors as $code => $messages ) {
 			foreach ( (array) $messages as $message ) {
-				$data[] = array( 'code' => $code, 'message' => $message, 'data' => $error->get_error_data( $code ) );
+				$errors[] = array( 'code' => $code, 'message' => $message, 'data' => $error->get_error_data( $code ) );
 			}
 		}
 
+		$data = $errors[0];
+		if ( count( $errors ) > 1 ) {
+			// Remove the primary error.
+			array_shift( $errors );
+			$data['additional_errors'] = $errors;
+		}
+
 		$response = new WP_REST_Response( $data, $status );
 
 		return $response;
@@ -198,7 +205,7 @@ class WP_REST_Server {
 
 		$error = compact( 'code', 'message' );
 
-		return wp_json_encode( array( $error ) );
+		return wp_json_encode( $error );
 	}
 
 	/**
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 194f88b4c5..39ed1ce034 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.4-beta4-35652';
+$wp_version = '4.4-beta4-35653';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.