<?php
/**
* Back compat functionality
*
* Prevents the theme from running on WordPress versions prior to 5.3,
* since this theme is not meant to be backward compatible beyond that and
* relies on many newer functions and markup changes introduced in 5.3.
*
* @package WordPress
* @subpackage Twenty_Twenty_One
* @since Twenty Twenty-One 1.0
*/
/**
* Display upgrade notice on theme switch.
*
* @since Twenty Twenty-One 1.0
*
* @return void
*/
function twenty_twenty_one_switch_theme() {
add_action( 'admin_notices', 'twenty_twenty_one_upgrade_notice' );
}
add_action( 'after_switch_theme', 'twenty_twenty_one_switch_theme' );
/**
* Adds a message for unsuccessful theme switch.
*
* Prints an update nag after an unsuccessful attempt to switch to
* the theme on WordPress versions prior to 5.3.
*
* @since Twenty Twenty-One 1.0
*
* @global string $wp_version WordPress version.
*
* @return void
*/
function twenty_twenty_one_upgrade_notice() {
echo '<div class="error"><p>';
printf(
/* translators: %s: WordPress Version. */
esc_html__( 'This theme requires WordPress 5.3 or newer. You are running version %s. Please upgrade.', 'twentytwentyone' ),
esc_html( $GLOBALS['wp_version'] )
);
echo '</p></div>';
}
/**
* Prevents the Customizer from being loaded on WordPress versions prior to 5.3.
*
* @since Twenty Twenty-One 1.0
*
* @global string $wp_version WordPress version.
*
* @return void
*/
function twenty_twenty_one_customize() {
wp_die(
sprintf(
/* translators: %s: WordPress Version. */
esc_html__( 'This theme requires WordPress 5.3 or newer. You are running version %s. Please upgrade.', 'twentytwentyone' ),
esc_html( $GLOBALS['wp_version'] )
),
'',
array(
'back_link' => true,
)
);
}
add_action( 'load-customize.php', 'twenty_twenty_one_customize' );
/**
* Prevents the Theme Preview from being loaded on WordPress versions prior to 5.3.
*
* @since Twenty Twenty-One 1.0
*
* @global string $wp_version WordPress version.
*
* @return void
*/
function twenty_twenty_one_preview() {
if ( isset( $_GET['preview'] ) ) { // phpcs:ignore WordPress.Security.NonceVerification
wp_die(
sprintf(
/* translators: %s: WordPress Version. */
esc_html__( 'This theme requires WordPress 5.3 or newer. You are running version %s. Please upgrade.', 'twentytwentyone' ),
esc_html( $GLOBALS['wp_version'] )
)
);
}
}
add_action( 'template_redirect', 'twenty_twenty_one_preview' );