test for the polyfill for the .endsWith method

by Alexander Zonov

JavaScript

function endsWith(str, postfix) {
	return str.endsWith(postfix);
}

// usefull to get functionality of the endsWith within IE 11
function polyfill(str, postfix) {
	return str.slice(str.length - postfix.length) === postfix;
}

var valid = ['stringPostfix', 'Postfix'];
var invalid = ['stringPostfix', 'Prefix'];

document.documentElement.append(
	'valid input: ' + 
	(endsWith(valid[0], valid[1]) === polyfill(valid[0], valid[1])) + 
	' ||| '
);

document.documentElement.append(
	'invalid input: ' + 
	(endsWith(invalid[0], invalid[1]) === polyfill(invalid[0], invalid[1]))
);