单元测试数据存储在PHP

Question

我使用的是PHPUnit的，但很难使其创造良好的嘲弄和存根作为数据存储的对象。

示例：

class urlDisplayer {
    private $storage;
    public function __construct(IUrlStorage $storage) { $this->storage = $storage; }
    public function displayUrl($name) {}
    public function displayLatestUrls($count) {}
}

interface IUrlStorage {
    public function addUrl($name, $url);
    public function getUrl($name);
}

class MysqlUrlStorage implements IUrlStorage {
    // saves and retrieves from database
}

class NonPersistentStorage implements IUrlStorage {
    // just stores for this request
}

例如，如何有PHPUnit的存根上有不同的名称$两次调用返回一个以上的可能值？

编辑：试验例：

public function testUrlDisplayerDisplaysLatestUrls {
    // get mock storage and have it return latest x urls so I can test whether
    // UrlDisplayer really shows the latest x
}

在本试验模拟应的文档中但是返回多个URL，我只如何返回一个值。

Answer 1

您的问题不是很清楚 - 但我以为你是问如何使用PHPUnit的mock对象在不同情况下返回不同的值

？

PHPUnit的模拟类允许您指定自定义功能（即：一个回调函数/法） - 这是它能做什么几乎是无限的。

在下面的例子中，我创建一个模拟IUrlStorage类，将每个被调用时返回下一个URL在其存储。

public function setUp()
{
    parent::setUp();
    $this->fixture = new UrlDisplayer(); //change this to however you create your object

    //Create a list of expected URLs for testing across all test cases
    $this->expectedUrls = array(
          'key1' => 'http://www.example.com/url1/'
        , 'key2' => 'http://www.example.net/url2/'
        , 'key3' => 'http://www.example.com/url3/'
    );
}

public function testUrlDisplayerDisplaysLatestUrls {
    //Init        
    $mockStorage = $this->getMock('IUrlStorage');
    $mockStorage->expects($this->any())
        ->method('getUrl')
        ->will( $this->returnCallback(array($this, 'mockgetUrl')) );

    reset($this->expectedUrls); //reset array before testing

    //Actual Tests
    $this->assertGreaterThan(0, count($this->expectedUrls));
    foreach ( $this->expectedUrls as $key => $expected ) {
        $actual = $this->fixture->displayUrl($key);
        $this->assertEquals($expected, $actual);
    }
}

public function mockGetUrl($name)
{
    $value = current($this->expectedUrls);
    next($this->expectedUrls);

    //Return null instead of false when end of array is reached
    return ($value === false) ? null : $value;
}

---

可选地，有时更容易简单地创建嘲笑了必要的功能性的真实类。这是具有良好定义和小接口特别容易。

在该特定情况下，我建议使用以下类，而不是：

class MockStorage implements IUrlStorage
{
    protected $urls = array();

    public function addUrl($name, $url)
    {
        $this->urls[$name] = $url;
    }

    public function getUrl($name)
    {
        if ( isset($this->urls[$name]) ) {
            return $this->urls[$name];
        }
        return null;
    }
}
?>

然后，在单元测试类只需要简单的夹具象下面这样：

public function setUp() {
   $mockStorage = new MockStorage();

   //Add as many expected URLs you want to test for
   $mockStorage->addUrl('name1', 'http://example.com');
   //etc...

   $this->fixture = new UrlDisplayer($mockStorage);
}