### 测试模型实体
> module/Album/test/Model/AlbumTest.php
```php
<?php
namespace AlbumTest\Model;
use Album\Model\Album;
use PHPUnit\Framework\TestCase;
class AlbumTest extends TestCase
{
public function testInitialAlbumValuesAreNull()
{
$album = new Album();
$this->assertNull($album->artist, '"artist" should be null by default');
$this->assertNull($album->id, '"id" should be null by default');
$this->assertNull($album->title, '"title" should be null by default');
}
public function testExchangeArraySetsPropertiesCorrectly()
{
$album = new Album();
$data = [
'artist' => 'some artist',
'id' => 123,
'title' => 'some title'
];
$album->exchangeArray($data);
$this->assertSame(
$data['artist'],
$album->artist,
'"artist" was not set correctly'
);
$this->assertSame(
$data['id'],
$album->id,
'"id" was not set correctly'
);
$this->assertSame(
$data['title'],
$album->title,
'"title" was not set correctly'
);
}
public function testExchangeArraySetsPropertiesToNullIfKeysAreNotPresent()
{
$album = new Album();
$album->exchangeArray([
'artist' => 'some artist',
'id' => 123,
'title' => 'some title',
]);
$album->exchangeArray([]);
$this->assertNull($album->artist, '"artist" should default to null');
$this->assertNull($album->id, '"id" should default to null');
$this->assertNull($album->title, '"title" should default to null');
}
public function testGetArrayCopyReturnsAnArrayWithPropertyValues()
{
$album = new Album();
$data = [
'artist' => 'some artist',
'id' => 123,
'title' => 'some title'
];
$album->exchangeArray($data);
$copyArray = $album->getArrayCopy();
$this->assertSame($data['artist'], $copyArray['artist'], '"artist" was not set correctly');
$this->assertSame($data['id'], $copyArray['id'], '"id" was not set correctly');
$this->assertSame($data['title'], $copyArray['title'], '"title" was not set correctly');
}
public function testInputFiltersAreSetCorrectly()
{
$album = new Album();
$inputFilter = $album->getInputFilter();
$this->assertSame(3, $inputFilter->count());
$this->assertTrue($inputFilter->has('artist'));
$this->assertTrue($inputFilter->has('id'));
$this->assertTrue($inputFilter->has('title'));
}
}
```
