Hide test gateway if a user is not an admin

hide-testmode-conditionally.php

<?php

add_filter( 'option_custom_gateway_options', 'js_gateway_options' );

function js_gateway_options( $gateways ) {
	
	if ( in_array( 'wpsc_merchant_testmode', $gateways ) && ! current_user_can( 'manage_options' ) ) {
		unset( $gateways[ array_search( 'wpsc_merchant_testmode', $gateways ) ] );
	}

	return $gateways;

}