From da40e89d06299b70d9c65b55d56c9a3e2f140b29 Mon Sep 17 00:00:00 2001
From: Jeremy Felt <jeremy.felt@gmail.com>
Date: Wed, 13 Jul 2016 04:46:28 +0000
Subject: [PATCH] Meta: Ensure filters are backwards compatible for pre-4.6
 style meta registration.

When using `register_meta()` with the function signature from 4.5 and earlier, the `auth_{$type}_meta_{$key}` and `sanitize_{$type}_meta_{$key}` filters are used. Any calls to `register_meta()` expecting this behavior should continue to work. The new filters, which take advantage of object subtypes, should not be added unless the proper `$args` array is passed.

See #35658.

Built from https://develop.svn.wordpress.org/trunk@38041


git-svn-id: http://core.svn.wordpress.org/trunk@37982 1a063a9b-81f0-0310-95a4-ce76da25c4cd
---
 wp-includes/meta.php    | 15 +++++++++++----
 wp-includes/version.php |  2 +-
 2 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/wp-includes/meta.php b/wp-includes/meta.php
index e341bd2bcc..ff32086725 100644
--- a/wp-includes/meta.php
+++ b/wp-includes/meta.php
@@ -1032,6 +1032,7 @@ function register_meta( $object_type, $meta_key, $args, $deprecated = null ) {
 
 	// There used to be individual args for sanitize and auth callbacks
 	$has_old_sanitize_cb = false;
+	$has_old_auth_cb = false;
 
 	if ( is_callable( $args ) ) {
 		$args = array(
@@ -1045,6 +1046,7 @@ function register_meta( $object_type, $meta_key, $args, $deprecated = null ) {
 
 	if ( is_callable( $deprecated ) ) {
 		$args['auth_callback'] = $deprecated;
+		$has_old_auth_cb = true;
 	}
 
 	$args = wp_parse_args( $args, $defaults );
@@ -1062,7 +1064,7 @@ function register_meta( $object_type, $meta_key, $args, $deprecated = null ) {
 	$args = apply_filters( 'register_meta_args', $args, $defaults, $object_type, $meta_key );
 
 	// Object subtype is required if using the args style of registration
-	if ( ! $has_old_sanitize_cb && empty( $args['object_subtype'] ) ) {
+	if ( ! $has_old_sanitize_cb && ! $has_old_auth_cb && empty( $args['object_subtype'] ) ) {
 		return new WP_Error( 'register_meta_failed', __( 'Meta must be registered against an object subtype.' ) );
 	}
 
@@ -1081,11 +1083,16 @@ function register_meta( $object_type, $meta_key, $args, $deprecated = null ) {
 		$object_subtype = $args['object_subtype'];
 	}
 
-	// Back-compat: old sanitize and auth callbacks applied to all of an object type
-	if ( $has_old_sanitize_cb ) {
+	// Back-compat: old sanitize and auth callbacks are applied to all of an object type.
+	if ( $has_old_sanitize_cb && is_callable( $args['sanitize_callback'] ) ) {
 		add_filter( "sanitize_{$object_type}_meta_{$meta_key}", $args['sanitize_callback'], 10, 4 );
+	}
+
+	if ( $has_old_auth_cb && is_callable( $args['auth_callback'] ) ) {
 		add_filter( "auth_{$object_type}_meta_{$meta_key}", $args['auth_callback'], 10, 6 );
-	} else {
+	}
+
+	if ( ! $has_old_auth_cb && ! $has_old_sanitize_cb) {
 		if ( is_callable( $args['sanitize_callback'] ) ) {
 			add_filter( "sanitize_{$object_type}_{$object_subtype}_meta_{$meta_key}", $args['sanitize_callback'], 10, 4 );
 		}
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 64bf163f19..67fb0d52ee 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.6-beta2-38040';
+$wp_version = '4.6-beta2-38041';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.