php7 psr-4作曲家自动加载

Question

我正在尝试使用自动加载psr4创建一个新项目。当我运行测试时，我得到错误。找不到这门课。我该如何解决？

编辑：我添加了phpunit.xml。我使用的是phpunit 6.5。

错误：Class＆＃39; FizzBu​​zz \ FizzBu​​zz＆＃39;找不到

/Sites/fizzbuzz/tests/FizzBu​​zzTest.php:15

composer.json

{
"require": {
},
"autoload": {
    "psr-4": {
        "FizzBuzz\\": "src/"
    }
}
}

FizzBu​​zzTest.php

<?php

use FizzBuzz\FizzBuzz;

class FizzBuzzTest extends PHPUnit_Framework_TestCase
{

    public function test_example(){
        $parser = new FizzBuzz();
        $this->assertEquals(0, $parser->parse());
    }
}

FizzBu​​zz.php

<?php

namespace FizzBuzz;

class FizzBuzz
{
    public function parse(){
        return 0;
    }
}

phpunit.xml

<?xml version="1.0" encoding="UTF-8"?>
<phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:noNamespaceSchemaLocation="phpunit.xsd"
     bootstrap="tests/bootstrap.php"
     verbose="true">
<testsuites>
    <testsuite name="small">
        <directory suffix="Test.php">tests/Framework</directory>
        <directory suffix="Test.php">tests/Runner</directory>
        <directory suffix="Test.php">tests/Util</directory>
    </testsuite>

    <testsuite name="large">
        <directory suffix=".phpt">tests/TextUI</directory>
        <directory suffix=".phpt">tests/Regression</directory>
    </testsuite>
</testsuites>

<filter>
    <whitelist processUncoveredFilesFromWhitelist="true">
        <directory suffix=".php">src</directory>
        <exclude>
            <file>src/Framework/Assert/Functions.php</file>
            <file>src/Util/PHP/eval-stdin.php</file>
        </exclude>
    </whitelist>
</filter>

<php>
    <const name="PHPUNIT_TESTSUITE" value="true"/>
</php>