From 35fb05f30de9580a0a94976c7bf95e82a731c2d7 Mon Sep 17 00:00:00 2001
From: Sergey Biryukov <sergeybiryukov.ru@gmail.com>
Date: Fri, 30 Sep 2022 00:40:11 +0000
Subject: [PATCH] Code Modernization: Fix null to non-nullable deprecation in
 `WP_Theme_JSON::get_property_value()`.

This commit aims to fix errors caused by incorrect usage of the `strncmp()` function inside the `WP_Theme_JSON::get_property_value()` method on PHP 8.1 and above.

Some history of the affected code:
* [50973] introduced the `WP_Theme_JSON::get_property_value()` method.
* [54162] removed the `$default` parameter from the `_wp_array_get()` call in the method.

With the latter change, the default value that is returned if the path does not exist within the array, or if `$array` or `$path` are not arrays, became `null` instead of an empty string. Since `null` would then be unintentionally passed to the `strncmp()` function further in the code, this caused ~35 errors in the test suite along the lines of:
{{{
1) Tests_Blocks_Editor::test_get_block_editor_settings_theme_json_settings
strncmp(): Passing null to parameter #1 ($string1) of type string is deprecated

/var/www/src/wp-includes/class-wp-theme-json.php:1754
/var/www/src/wp-includes/class-wp-theme-json.php:1641
/var/www/src/wp-includes/class-wp-theme-json.php:2066
/var/www/src/wp-includes/class-wp-theme-json.php:1002
/var/www/src/wp-includes/class-wp-theme-json.php:898
/var/www/src/wp-includes/global-styles-and-settings.php:140
/var/www/src/wp-includes/block-editor.php:421
/var/www/tests/phpunit/tests/blocks/editor.php:388
/var/www/vendor/bin/phpunit:123
}}}

This commit includes:
* Restoring the `$default` value for `_wp_array_get()` call.
* Adding an early return if the value is an empty string or `null`.
* Adding a dedicated unit test to ensure that the method returns a string for invalid paths or `null` values.

Follow-up to [50973], [54162].

Props antonvlasenko, jrf, imadarshakshat, SergeyBiryukov.
Fixes #56620.
Built from https://develop.svn.wordpress.org/trunk@54362


git-svn-id: http://core.svn.wordpress.org/trunk@53921 1a063a9b-81f0-0310-95a4-ce76da25c4cd
---
 wp-includes/class-wp-theme-json.php | 7 ++++++-
 wp-includes/version.php             | 2 +-
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/wp-includes/class-wp-theme-json.php b/wp-includes/class-wp-theme-json.php
index 749ee90c0c..4f5627a790 100644
--- a/wp-includes/class-wp-theme-json.php
+++ b/wp-includes/class-wp-theme-json.php
@@ -1709,7 +1709,12 @@ class WP_Theme_JSON {
 	 * @return string|array Style property value.
 	 */
 	protected static function get_property_value( $styles, $path, $theme_json = null ) {
-		$value = _wp_array_get( $styles, $path );
+		$value = _wp_array_get( $styles, $path, '' );
+
+		if ( '' === $value || null === $value ) {
+			// No need to process the value further.
+			return '';
+		}
 
 		/*
 		 * This converts references to a path to the value at that path
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 69b0de7a79..d25e0081bc 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '6.1-beta2-54361';
+$wp_version = '6.1-beta2-54362';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.