From f5aa4c90bcf8cccc433a0b2b37f4b77a0e4b518e Mon Sep 17 00:00:00 2001
From: hellofromTonya <hellofromTonya@git.wordpress.org>
Date: Tue, 18 Jun 2024 14:46:10 +0000
Subject: [PATCH] Code Modernization: Fix non-nullable deprecation in
 get_available_post_mime_types().

Fixes a PHP 8.1 and above "null to non-nullable" deprecation notice in `get_available_post_mime_types()`:

{{{
Deprecated: preg_match(): Passing null to parameter #2 ($subject) of type string is deprecated in ./wp-includes/post.php on line 3395
}}}

[https://developer.wordpress.org/reference/functions/get_available_post_mime_types/#return This function is documented] to:
* Return `An array of MIME types.`
* as an array of `string`s, i.e. `string[]`.

A `null` or empty element within the returned array is not a valid MIME type. If a `null` exists in the returned array, it is the root cause of PHP throwing the deprecation notice.

This commit removes the `null` and empty elements from the returned array of MIME types. It also adds a unit test.

Follow-up to [56623], [56452].

Props nosilver4u, jrf, ironprogrammer, antpb, antonvlasenko, rajinsharwar, hellofromTonya.
Fixes #59195.
Built from https://develop.svn.wordpress.org/trunk@58437


git-svn-id: http://core.svn.wordpress.org/trunk@57886 1a063a9b-81f0-0310-95a4-ce76da25c4cd
---
 wp-includes/post.php    | 5 +++--
 wp-includes/version.php | 2 +-
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/wp-includes/post.php b/wp-includes/post.php
index 2f7cba613f..993056ff2c 100644
--- a/wp-includes/post.php
+++ b/wp-includes/post.php
@@ -8094,10 +8094,11 @@ function get_available_post_mime_types( $type = 'attachment' ) {
 	$mime_types = apply_filters( 'pre_get_available_post_mime_types', null, $type );
 
 	if ( ! is_array( $mime_types ) ) {
-		$mime_types = $wpdb->get_col( $wpdb->prepare( "SELECT DISTINCT post_mime_type FROM $wpdb->posts WHERE post_type = %s", $type ) );
+		$mime_types = $wpdb->get_col( $wpdb->prepare( "SELECT DISTINCT post_mime_type FROM $wpdb->posts WHERE post_type = %s AND post_mime_type != ''", $type ) );
 	}
 
-	return $mime_types;
+	// Remove nulls from returned $mime_types.
+	return array_values( array_filter( $mime_types ) );
 }
 
 /**
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 45917072ae..cbf661fdf0 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '6.6-beta2-58436';
+$wp_version = '6.6-beta2-58437';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.