From de7375b5d1d7a054a8d43da52d78384270dadb52 Mon Sep 17 00:00:00 2001
From: Andrew Nacin <wp@andrewnacin.com>
Date: Wed, 17 Jul 2013 04:46:09 +0000
Subject: [PATCH] Avoid a sanitize_key() call on ID, as this causes it to be
 lowercased. wp_dropdown_users() requires user_login as a fallback; specify it
 for get_users(). see #21767.

git-svn-id: http://core.svn.wordpress.org/trunk@24719 1a063a9b-81f0-0310-95a4-ce76da25c4cd
---
 wp-includes/user.php | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/wp-includes/user.php b/wp-includes/user.php
index 9d307d3d01..bc583a5789 100644
--- a/wp-includes/user.php
+++ b/wp-includes/user.php
@@ -392,8 +392,10 @@ class WP_User_Query {
 			$qv['fields'] = array_unique( $qv['fields'] );
 
 			$this->query_fields = array();
-			foreach ( $qv['fields'] as $field )
-				$this->query_fields[] = $wpdb->users . '.' . sanitize_key( $field );
+			foreach ( $qv['fields'] as $field ) {
+				$field = 'ID' === $field ? 'ID' : sanitize_key( $field );
+				$this->query_fields[] = "$wpdb->users.$field";
+			}
 			$this->query_fields = implode( ',', $this->query_fields );
 		} elseif ( 'all' == $qv['fields'] ) {
 			$this->query_fields = "$wpdb->users.*";
@@ -1029,7 +1031,7 @@ function wp_dropdown_users( $args = '' ) {
 	extract( $r, EXTR_SKIP );
 
 	$query_args = wp_array_slice_assoc( $r, array( 'blog_id', 'include', 'exclude', 'orderby', 'order', 'who' ) );
-	$query_args['fields'] = array( 'ID', $show );
+	$query_args['fields'] = array( 'ID', 'user_login', $show );
 	$users = get_users( $query_args );
 
 	$output = '';