Call to _admin_bar_bump_cb causes deprecation error in WordPress 6.4+

[tofumatt]

Bug Description

The call to _admin_bar_bump_cb at https://github.com/ampproject/amp-wp/blob/2c4df9e1dec74c798e11f06cd02e470f1f988705/includes/class-amp-theme-support.php#L1226C9-L1226C9 causes PHP Deprecation notices to appear when using the AMP plugin with WordPress 6.4+.

The entire notice is:

PHP Deprecated:  Function _admin_bar_bump_cb is deprecated since version 6.4.0! Use wp_enqueue_admin_bar_bump_styles instead. in /var/www/html/wp-includes/functions.php on line 6032

It seems using wp_enqueue_admin_bar_bump_styles instead will fix the issue, when the version of WordPress is equal-to/above 6.4.0.

Expected Behaviour

No deprecation errors appear in the WordPress debug log/elsewhere when using the AMP plugin with WordPress 6.4+.

Screenshots

PHP Version

7.4

Plugin Version

2.4.2

AMP plugin template mode

Standard

WordPress Version

6.4.0 (Nightly)

Site Health

No response

Gutenberg Version

No response

OS(s) Affected

No response

Browser(s) Affected

No response

Device(s) Affected

No response

Acceptance Criteria

No response

Implementation Brief

No response

QA Testing Instructions

No response

Demo

No response

Changelog Entry

No response

[westonruter]

Yes, this is result of https://core.trac.wordpress.org/ticket/58775

We'll need to fix by the time WordPress 6.4 is released.

As for the fix, the code in question is:

amp-wp/includes/class-amp-theme-support.php

Lines 1228 to 1241 in 2c4df9e

	remove_action( 'wp_head', $header_callback );
	if ( '__return_false' !== $header_callback ) {
	ob_start();
	$header_callback();
	$style = ob_get_clean();
	$data = trim( preg_replace( '#<style[^>]*>(.*)</style>#is', '$1', $style ) ); // See wp_add_inline_style().
	// Override AMP's position:relative on the body for the sake of the AMP viewer, which is not relevant an an Admin Bar context.
	if ( amp_is_dev_mode() ) {
	$data .= 'html:not(#_) > body { position:unset !important; }';
	}
	wp_add_inline_style( 'admin-bar', $data );
	}

I believe it can be rewritten as follows, or something like it:

if ( ! function_exists( 'wp_enqueue_admin_bar_header_styles' ) ) {
    remove_action( 'wp_head', $header_callback );
}
 if ( '__return_false' !== $header_callback ) { 
 	if ( ! function_exists( 'wp_enqueue_admin_bar_header_styles' ) ) {
 		ob_start(); 
 		$header_callback(); 
 		$style = ob_get_clean(); 
 		$data  = trim( preg_replace( '#<style[^>]*>(.*)</style>#is', '$1', $style ) ); // See wp_add_inline_style(). 
 	} else {
 		$data = '';
 	}
  
 	// Override AMP's position:relative on the body for the sake of the AMP viewer, which is not relevant an an Admin Bar context. 
 	if ( amp_is_dev_mode() ) { 
 		$data .= 'html:not(#_) > body { position:unset !important; }'; 
 	} 
  
 	wp_add_inline_style( 'admin-bar', $data ); 
 }

[westonruter]

cc @spacedmonkey

[pavanpatil1]

QA Passed ✅

Cross-verified the issue and the applied solution is functioning correctly. Now, the deprecation warning related to the _admin_bar_bump_cb is not visible.

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