From 256272e534f4085a419a56eed5e80ecb435432b1 Mon Sep 17 00:00:00 2001
From: Peter Wilson <wilson@peterwilson.cc>
Date: Wed, 14 Jun 2023 23:51:22 +0000
Subject: [PATCH] Taxonomy: Prevent deprecation notices clearing terms.

Prevents `wp_set_object_terms()` throwing a deprecation notice in PHP 8.1+ when passing an empty value as the second parameter to clear the terms.

Props audrasjb, chouby, costdev, jrf, peterwilsoncc, prashantbhivsane, sergeybiryukov.
Fixes #57923.

Built from https://develop.svn.wordpress.org/trunk@55921


git-svn-id: http://core.svn.wordpress.org/trunk@55433 1a063a9b-81f0-0310-95a4-ce76da25c4cd
---
 wp-includes/taxonomy.php | 6 ++++--
 wp-includes/version.php  | 2 +-
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/wp-includes/taxonomy.php b/wp-includes/taxonomy.php
index 71280f0437..35031e3bef 100644
--- a/wp-includes/taxonomy.php
+++ b/wp-includes/taxonomy.php
@@ -2737,7 +2737,7 @@ function wp_insert_term( $term, $taxonomy, $args = array() ) {
  * @param int              $object_id The object to relate to.
  * @param string|int|array $terms     A single term slug, single term ID, or array of either term slugs or IDs.
  *                                    Will replace all existing related terms in this taxonomy. Passing an
- *                                    empty value will remove all related terms.
+ *                                    empty array will remove all related terms.
  * @param string           $taxonomy  The context in which to relate the term to the object.
  * @param bool             $append    Optional. If false will delete difference of terms. Default false.
  * @return array|WP_Error Term taxonomy IDs of the affected terms or WP_Error on failure.
@@ -2751,7 +2751,9 @@ function wp_set_object_terms( $object_id, $terms, $taxonomy, $append = false ) {
 		return new WP_Error( 'invalid_taxonomy', __( 'Invalid taxonomy.' ) );
 	}
 
-	if ( ! is_array( $terms ) ) {
+	if ( empty( $terms ) ) {
+		$terms = array();
+	} elseif ( ! is_array( $terms ) ) {
 		$terms = array( $terms );
 	}
 
diff --git a/wp-includes/version.php b/wp-includes/version.php
index bd5cd5f751..474dc5846b 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '6.3-alpha-55920';
+$wp_version = '6.3-alpha-55921';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.