Check if a custom post type supports archives

cpt_has_archive.php

<?php
/**
 * Check if post type supports an archive
 *
 * @param string $post_type post type name
 * @uses get_post_type
 * @global object $post
 * @returns boolean
 * @author Joshua David Nelson
 */
if( !function_exists( 'cpt_has_archive' ) ) {
	function cpt_has_archive( $post_type ) {
		if( !is_string( $post_type ) || !isset( $post_type ) )
			return false;
		
		// find custom post types with archvies
		$args = array(
			'has_archive'	=> true,
			'_builtin'	=> false,
		);
		$output = 'names';
		$archived_custom_post_types = get_post_types( $args, $output );
		
		// if there are no custom post types, then the current post can't be one
		if( empty( $archived_custom_post_types ) )
			return false;
		
		// check if post type is a supports archives
		if ( in_array( $post_type, $archived_custom_post_types ) ) {
		        return true;
		} else {
		        return false;
		}
		
		// if all else fails, return false
		return false;	
		
	}
}