<?php

function autoloader($dir){

    spl_autoload_register(function($name) use ($dir){

        $name = str_replace('\\',DIRECTORY_SEPARATOR,$name);

        require $dir.DIRECTORY_SEPARATOR.$name.'.php';

    });

}

define('ROOT',__DIR__);

autoloader(ROOT);

<?php

class Money

{

    private $amount;

    public function __construct($amount)

    {

        $this->amount = $amount;

    }

    public function getAmount()

    {

        return $this->amount;

    }

    public function negate()

    {

        return new Money(-1*$this->amount);

    }

}

<?php

use PHPUnit\Framework\TestCase;

class MoneyTest extends TestCase

{

    public function testCanBeNegated()

    {

        $a = new Money(1);

        $b = $a->negate();

        $this->assertEquals(-1, $b->getAmount());

    }

}

AssertTrue/AssertFalse    断言是否为真值还是假

AssertEquals　　　　　　　　判断输出是否和预期的相等

AssertGreaterThan         断言结果是否大于某个值，同样的也有LessThan(小于),GreaterThanOrEqual(大于等于)，

LessThanOrEqual           (小于等于).

AssertContains            判断输入是否包含指定的值

AssertType                判断是否属于指定类型

AssertNull                判断是否为空值

AssertFileExists          判断文件是否存在

AssertRegExp              根据正则表达式判断