WordPress at a glance
function is not described

WP_Customize_Manager::theme() public WP 3.4.0

Get the theme being customized.

{} It's a method of the class: WP_Customize_Manager{}

No Hooks.

Return

WP_Theme.

Usage

$WP_Customize_Manager = new WP_Customize_Manager();
$WP_Customize_Manager->theme();

Changelog

Since 3.4.0 Introduced.

Code of WP_Customize_Manager::theme() WP 5.7.2

<?php
public function theme() {
	if ( ! $this->theme ) {
		$this->theme = wp_get_theme();
	}
	return $this->theme;
}