Test PHP `DateTime(date())` vs `if(can call DateTime->setTimestamp) DateTime->setTimestamp() else DateTime(date())`

test_datetime.php

<?php

/*
 * Test how calling `DateTime(date())` compares to checking for `DateTime::createFromFormat()`
 * or `DateTime->setTimestamp()` and using `date()` as fallback only.
 *
 * Output should show something like:
 *
 * 	Using date() without any check: 4.3791408538818s
 * 	Using DateTime::createFromFormat(): 5.6960089206696s
 * 	Using DateTime->setTimestamp(): 3.3501291275024s
 *
 */

	$string = time();

	// Benchmark code without function check
	$start = microtime(true);
	for ($i = 100000; $i > 0; $i--) {
		if (is_numeric($string)) {
			$date = new DateTime(date(DateTime::ISO8601, $string));
		}
	}
	$end = microtime(true) - $start;
	echo "Using date() without any check: {$end}s\n";

	// Benchmark code that checks if method exists
	$start = microtime(true);
	for ($i = 100000; $i > 0; $i--) {
		if(is_numeric($string)) {
			if (method_exists('DateTime', 'createFromFormat')) {
				$date = DateTime::createFromFormat('U', $string);
			}
			else {
				$date = new DateTime(date(DateTime::ISO8601, $string));
			}
		}
	}
	$end = microtime(true) - $start;
	echo "Using DateTime::createFromFormat(): {$end}s\n";

	// Benchmark code that checks if method exists
	$start = microtime(true);
	for ($i = 100000; $i > 0; $i--) {
		if(is_numeric($string)) {
			if (method_exists('DateTime', 'setTimestamp')) {
				$date = new DateTime();
				$date->setTimestamp($string);
			}
			else {
				$date = new DateTime(date(DateTime::ISO8601, $string));
			}
		}
	}
	$end = microtime(true) - $start;
	echo "Using DateTime->setTimestamp(): {$end}s\n";