From 559e6cecf49505ecc3a21fbff647fdc5c3f892a3 Mon Sep 17 00:00:00 2001
From: Jonny Harris <spacedmonkey@git.wordpress.org>
Date: Tue, 13 Jun 2023 09:51:11 +0000
Subject: [PATCH] Script Loader: Add a check to see in style is registered in
 wp_maybe_inline_styles.

Add a check in `wp_maybe_inline_styles` to check that style is registered before processing items in queue. It is possible that developers may have called `wp_deregister_style`, unregistering style but the style still be in the queue to be processed. Without this check, typing to access the `src` property would result in a notice error.

Follow on from [55888].

Props spacedmonkey, flixos90, dd32, kebbet.
See #58394.

git-svn-id: https://develop.svn.wordpress.org/trunk@55909 602fd350-edb4-49c9-b593-d223f7449a82
---
 src/wp-includes/script-loader.php           |  5 ++++-
 tests/phpunit/tests/dependencies/styles.php | 20 ++++++++++++++++++++
 2 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/src/wp-includes/script-loader.php b/src/wp-includes/script-loader.php
index 9cd877a50f..76155ac226 100644
--- a/src/wp-includes/script-loader.php
+++ b/src/wp-includes/script-loader.php
@@ -2872,8 +2872,11 @@ function wp_maybe_inline_styles() {
 
 	// Build an array of styles that have a path defined.
 	foreach ( $wp_styles->queue as $handle ) {
+		if ( ! isset( $wp_styles->registered[ $handle ] ) ) {
+			continue;
+		}
 		$src  = $wp_styles->registered[ $handle ]->src;
-		$path = wp_styles()->get_data( $handle, 'path' );
+		$path = $wp_styles->get_data( $handle, 'path' );
 		if ( $path && $src ) {
 			$size = wp_filesize( $path );
 			if ( ! $size ) {
diff --git a/tests/phpunit/tests/dependencies/styles.php b/tests/phpunit/tests/dependencies/styles.php
index 798b75a252..4b1e46f21d 100644
--- a/tests/phpunit/tests/dependencies/styles.php
+++ b/tests/phpunit/tests/dependencies/styles.php
@@ -537,6 +537,26 @@ CSS;
 		$this->assertSameSets( $GLOBALS['wp_styles']->registered['test-handle']->extra['after'], array( $css ), 'Source of style should set to after property' );
 	}
 
+	/**
+	 * @ticket 58394
+	 *
+	 * @covers ::wp_maybe_inline_styles
+	 */
+	public function test_wp_maybe_inline_styles_dequeue_styles() {
+		$filter = new MockAction();
+		add_filter( 'pre_wp_filesize', array( $filter, 'filter' ) );
+		wp_register_style( 'test-handle', '/' . WPINC . '/css/classic-themes.css' );
+		wp_style_add_data( 'test-handle', 'path', ABSPATH . WPINC . '/css/classic-themes.css' );
+
+		wp_enqueue_style( 'test-handle' );
+
+		wp_deregister_style( 'test-handle' );
+
+		wp_maybe_inline_styles();
+
+		$this->assertSame( 0, $filter->get_call_count() );
+	}
+
 	/**
 	 * wp_filesize should be only be called once, as on the second run of wp_maybe_inline_styles,
 	 * src will be set to false and filesize will not be requested.