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A WordPress-centric search engine for devs and theme authors

function get_stylesheet_directory() {
	global $wp_stylesheet_path;

	if ( null === $wp_stylesheet_path ) {
		$stylesheet     = get_stylesheet();
		$theme_root     = get_theme_root( $stylesheet );
		$stylesheet_dir = "$theme_root/$stylesheet";

		/**
		 * Filters the stylesheet directory path for the active theme.
		 *
		 * @since 1.5.0
		 *
		 * @param string $stylesheet_dir Absolute path to the active theme.
		 * @param string $stylesheet     Directory name of the active theme.
		 * @param string $theme_root     Absolute path to themes directory.
		 */
		$stylesheet_dir = apply_filters( 'stylesheet_directory', $stylesheet_dir, $stylesheet, $theme_root );

		// If there are filter callbacks, force the logic to execute on every call.
		if ( has_filter( 'stylesheet' ) || has_filter( 'theme_root' ) || has_filter( 'stylesheet_directory' ) ) {
			return $stylesheet_dir;
		}

		$wp_stylesheet_path = $stylesheet_dir;
	}

	return $wp_stylesheet_path;
}