diff -r be944660c56a -r 3d72ae0968f4 wp/wp-includes/cache-compat.php
--- a/wp/wp-includes/cache-compat.php	Wed Sep 21 18:19:35 2022 +0200
+++ b/wp/wp-includes/cache-compat.php	Tue Sep 27 16:37:53 2022 +0200
@@ -2,12 +2,72 @@
 /**
  * Object Cache API functions missing from 3rd party object caches.
  *
- * @link https://codex.wordpress.org/Class_Reference/WP_Object_Cache
+ * @link https://developer.wordpress.org/reference/classes/wp_object_cache/
  *
  * @package WordPress
  * @subpackage Cache
  */
 
+if ( ! function_exists( 'wp_cache_add_multiple' ) ) :
+	/**
+	 * Adds multiple values to the cache in one call, if the cache keys don't already exist.
+	 *
+	 * Compat function to mimic wp_cache_add_multiple().
+	 *
+	 * @ignore
+	 * @since 6.0.0
+	 *
+	 * @see wp_cache_add_multiple()
+	 *
+	 * @param array  $data   Array of keys and values to be added.
+	 * @param string $group  Optional. Where the cache contents are grouped. Default empty.
+	 * @param int    $expire Optional. When to expire the cache contents, in seconds.
+	 *                       Default 0 (no expiration).
+	 * @return bool[] Array of return values, grouped by key. Each value is either
+	 *                true on success, or false if cache key and group already exist.
+	 */
+	function wp_cache_add_multiple( array $data, $group = '', $expire = 0 ) {
+		$values = array();
+
+		foreach ( $data as $key => $value ) {
+			$values[ $key ] = wp_cache_add( $key, $value, $group, $expire );
+		}
+
+		return $values;
+	}
+endif;
+
+if ( ! function_exists( 'wp_cache_set_multiple' ) ) :
+	/**
+	 * Sets multiple values to the cache in one call.
+	 *
+	 * Differs from wp_cache_add_multiple() in that it will always write data.
+	 *
+	 * Compat function to mimic wp_cache_set_multiple().
+	 *
+	 * @ignore
+	 * @since 6.0.0
+	 *
+	 * @see wp_cache_set_multiple()
+	 *
+	 * @param array  $data   Array of keys and values to be set.
+	 * @param string $group  Optional. Where the cache contents are grouped. Default empty.
+	 * @param int    $expire Optional. When to expire the cache contents, in seconds.
+	 *                       Default 0 (no expiration).
+	 * @return bool[] Array of return values, grouped by key. Each value is either
+	 *                true on success, or false on failure.
+	 */
+	function wp_cache_set_multiple( array $data, $group = '', $expire = 0 ) {
+		$values = array();
+
+		foreach ( $data as $key => $value ) {
+			$values[ $key ] = wp_cache_set( $key, $value, $group, $expire );
+		}
+
+		return $values;
+	}
+endif;
+
 if ( ! function_exists( 'wp_cache_get_multiple' ) ) :
 	/**
 	 * Retrieves multiple values from the cache in one call.
@@ -23,7 +83,8 @@
 	 * @param string $group Optional. Where the cache contents are grouped. Default empty.
 	 * @param bool   $force Optional. Whether to force an update of the local cache
 	 *                      from the persistent cache. Default false.
-	 * @return array Array of values organized into groups.
+	 * @return array Array of return values, grouped by key. Each value is either
+	 *               the cache contents on success, or false on failure.
 	 */
 	function wp_cache_get_multiple( $keys, $group = '', $force = false ) {
 		$values = array();
@@ -35,3 +96,48 @@
 		return $values;
 	}
 endif;
+
+if ( ! function_exists( 'wp_cache_delete_multiple' ) ) :
+	/**
+	 * Deletes multiple values from the cache in one call.
+	 *
+	 * Compat function to mimic wp_cache_delete_multiple().
+	 *
+	 * @ignore
+	 * @since 6.0.0
+	 *
+	 * @see wp_cache_delete_multiple()
+	 *
+	 * @param array  $keys  Array of keys under which the cache to deleted.
+	 * @param string $group Optional. Where the cache contents are grouped. Default empty.
+	 * @return bool[] Array of return values, grouped by key. Each value is either
+	 *                true on success, or false if the contents were not deleted.
+	 */
+	function wp_cache_delete_multiple( array $keys, $group = '' ) {
+		$values = array();
+
+		foreach ( $keys as $key ) {
+			$values[ $key ] = wp_cache_delete( $key, $group );
+		}
+
+		return $values;
+	}
+endif;
+
+if ( ! function_exists( 'wp_cache_flush_runtime' ) ) :
+	/**
+	 * Removes all cache items from the in-memory runtime cache.
+	 *
+	 * Compat function to mimic wp_cache_flush_runtime().
+	 *
+	 * @ignore
+	 * @since 6.0.0
+	 *
+	 * @see wp_cache_flush_runtime()
+	 *
+	 * @return bool True on success, false on failure.
+	 */
+	function wp_cache_flush_runtime() {
+		return wp_using_ext_object_cache() ? false : wp_cache_flush();
+	}
+endif;