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function is not described

validate_theme_requirements() WP 5.5.0

Validates the theme requirements for WordPress version and PHP version.

Uses the information from Requires at least and Requires PHP headers defined in the theme's style.css file.

If the headers are not present in the theme's stylesheet file, readme.txt is also checked as a fallback.

No Hooks.

Return

true|WP_Error. True if requirements are met, WP_Error on failure.

Usage

validate_theme_requirements( $stylesheet );
$stylesheet(string) (required)
Directory name for the theme.

Changelog

Since 5.5.0 Introduced.

Code of validate_theme_requirements() WP 5.7.2

<?php
function validate_theme_requirements( $stylesheet ) {
	$theme = wp_get_theme( $stylesheet );

	$requirements = array(
		'requires'     => ! empty( $theme->get( 'RequiresWP' ) ) ? $theme->get( 'RequiresWP' ) : '',
		'requires_php' => ! empty( $theme->get( 'RequiresPHP' ) ) ? $theme->get( 'RequiresPHP' ) : '',
	);

	$readme_file = $theme->theme_root . '/' . $stylesheet . '/readme.txt';

	if ( file_exists( $readme_file ) ) {
		$readme_headers = get_file_data(
			$readme_file,
			array(
				'requires'     => 'Requires at least',
				'requires_php' => 'Requires PHP',
			),
			'theme'
		);

		$requirements = array_merge( $readme_headers, $requirements );
	}

	$compatible_wp  = is_wp_version_compatible( $requirements['requires'] );
	$compatible_php = is_php_version_compatible( $requirements['requires_php'] );

	if ( ! $compatible_wp && ! $compatible_php ) {
		return new WP_Error(
			'theme_wp_php_incompatible',
			sprintf(
				/* translators: %s: Theme name. */
				_x( '<strong>Error:</strong> Current WordPress and PHP versions do not meet minimum requirements for %s.', 'theme' ),
				$theme->display( 'Name' )
			)
		);
	} elseif ( ! $compatible_php ) {
		return new WP_Error(
			'theme_php_incompatible',
			sprintf(
				/* translators: %s: Theme name. */
				_x( '<strong>Error:</strong> Current PHP version does not meet minimum requirements for %s.', 'theme' ),
				$theme->display( 'Name' )
			)
		);
	} elseif ( ! $compatible_wp ) {
		return new WP_Error(
			'theme_wp_incompatible',
			sprintf(
				/* translators: %s: Theme name. */
				_x( '<strong>Error:</strong> Current WordPress version does not meet minimum requirements for %s.', 'theme' ),
				$theme->display( 'Name' )
			)
		);
	}

	return true;
}