<?php
/**
 *   This scripts is used to compare the speed
 * between in_array and switch.
 *
 * Author:    Angus.Fenying
 * Date:      2015-06-17
 * Blog:      http://fenying.blog.163.com
 */
class Test {

	public function main(array $args) {
		set_time_limit(0);

		/* 空白对照，只进行计数计时。*/

		$time_blank = [];
		for ($i = 0; $i < 10; ++$i)
			$time_blank[] = $this->test_blank($i);
		$time_blank = array_sum($time_blank) / count($time_blank);

		/* 测试当 in_array 命中时的速度 */

		$time_in_array_hit = [];
		for ($i = 0; $i < 10; ++$i)
			$time_in_array_hit[] = $this->test_in_array($i);
		$time_in_array_hit = array_sum($time_in_array_hit) / count($time_in_array_hit);

		/* 测试当 in_array 未命中时的速度 */

		$time_in_array_miss = [];
		for ($i = 5; $i < 10; ++$i)
			$time_in_array_miss[] = $this->test_in_array($i);
		$time_in_array_miss = array_sum($time_in_array_miss) / count($time_in_array_miss);

		/* 测试当 switch 命中时的速度 */

		$time_switch_hit = [];
		for ($i = 0; $i < 10; ++$i)
			$time_switch_hit[] = $this->test_switch($i);
		$time_switch_hit = array_sum($time_switch_hit) / count($time_switch_hit);

		/* 测试当 switch 未命中时的速度 */

		$time_switch_miss = [];
		for ($i = 5; $i < 10; ++$i)
			$time_switch_miss[] = $this->test_switch($i);
		$time_switch_miss = array_sum($time_switch_miss) / count($time_switch_miss);

		echo '<p>Blank: ', $time_blank, '</p>';
		echo '<p>in_array[hit]: ', $time_in_array_hit, '</p>';
		echo '<p>in_array[miss]: ', $time_in_array_miss, '</p>';
		echo '<p>switch[hit]: ', $time_switch_hit, '</p>';
		echo '<p>switch[miss]: ', $time_switch_miss, '</p>';
	}

	protected function test_blank($g) {
		$t0 = microtime(true);
		for ($k = 0; $k < 1000000;++$k);
		return microtime(true) - $t0;
	}

	protected function test_in_array($g) {
		$t0 = microtime(true);
		for ($k = 0; $k < 1000000;++$k)
			if (in_array($k, [0,1,2,3,4]));
			else;

		return microtime(true) - $t0;
	}

	protected function test_switch($g) {
		$t0 = microtime(true);
		for ($k = 0; $k < 1000000;++$k)
			switch ($g) {
			case 0:
			case 1:
			case 2:
			case 3:
			case 4:
				break;
			default:
			}

		return microtime(true) - $t0;
	}
}