今天讓我們回顧一下前一天的 Mocking 初體驗吧！
Mocking 初體驗回顧
- app/Repositories/UserRepository.php
<?php
namespace App\Repositories;
use App\Models\User;
class UserRepository{
protected $model;
public function __construct(User $model) {
$this->model = $model;
} public function getUserById($userId) {
return $this->model::find($userId);
}}
- app/Repositories/PostRepository.php
<?php
namespace App\Repositories;
class PostRepository{
protected $model;
}
- app/Services/UserService.php
<?php
namespace App\Services;
use App\Repositories\PostRepository;
use App\Repositories\UserRepository;
class UserService{
private $userRepository;
private $postRepository;
public function __construct( PostRepository $postRepository, UserRepository $userRepository ) {
$this->postRepository = $postRepository;
$this->userRepository = $userRepository;
} public function getUserData(int $userId) {
$user = $this->userRepository->getUserById($userId);
if (empty($user)) {
return [];
} $user->posts = $this->postRepository->getPostsByUserId($userId);
return $user;
}}
- tests/Feature/UserServiceTest.php
<?php
namespace Tests\Feature;
use App\Models\User;
use App\Repositories\PostRepository;
use App\Repositories\UserRepository;
use App\Services\UserService;
use Tests\TestCase;
class UserServiceTest extends TestCase{
public function testGetUserDataWhenUserNotFound() {
$this->mock(UserRepository::class, function ($mock) {
$mock->shouldReceive('getUserById')
->with(1)
->once()
->andReturn(null);
}); $service = app(UserService::class);
$user = $service->getUserData(1);
$this->assertEmpty($user);
} public function testGetUserData() {
$user = User::factory()->make();
$this->mock(UserRepository::class, function ($mock) use ($user) {
$mock->shouldReceive('getUserById')
->with(1)
->once()
->andReturn($user);
}); $this->mock(PostRepository::class, function ($mock) {
$mock->shouldReceive('getPostsByUserId')
->with(1)
->once()
->andReturn([]);
}); $service = app(UserService::class);
$user = $service->getUserData(1);
$this->assertNotEmpty($user);
$this->assertNotNull($user->posts);
}}
在前一天的 Mocking 初體驗中，我們有用到4個重要的 Mocking 函數，以下就針對它們做個簡單介紹吧！
Mocking 函數說明
shouldReceive()：當我們預期指定類別的某個函數，會在測試過程被呼叫，且希望 Mock 此函數的行為時，我們就會用到shouldReceive()來補捉這個呼叫行為，並且接著 Mock 該函數後續的行為。with()：此函數通常會接在shouldReceive()之後，用以補捉符合某種輸入參數組合的函數呼叫，並接著 Mock 該函數後續的行為。once()：此函數通常會接在with()之後，用以補捉只呼叫一次的函數呼叫，並接著 Mock 該函數後續的行為。andReturn()：此函數通常會接在with()或once之後，用以 Mock 函數的回應值。
測試案例導覽
- testGetUserDataWhenUserNotFound()
$this->mock(UserRepository::class, function ($mock) {在此案例中，我們 Mock 了
$mock->shouldReceive('getUserById')
->with(1)
->once() ->andReturn(null);});$service = app(UserService::class);
$user = $service->getUserData(1);
$this->assertEmpty($user);
UserRepository 這個類別，並且補捉 getUserById() 的 1次性函數呼叫，且此呼叫附帶的函數呼叫參數是 1，接著我們 Mock 它的回應為 null。- testGetUserData()
$user = User::factory()->make();
$this->mock(UserRepository::class, function ($mock) use ($user) {
$mock->shouldReceive('getUserById')
->with(1)
->once() ->andReturn($user);
});$this->mock(PostRepository::class, function ($mock) {
$mock->shouldReceive('getPostsByUserId')
->with(1)
->once() ->andReturn([]);});$service = app(UserService::class);
$user = $service->getUserData(1);
$this->assertNotEmpty($user);
$this->assertNotNull($user->posts);
在此案例中，我們同樣 Mock 了 UserRepository 這個類別，並且補捉 getUserById() 的 1次性函數呼叫，且此呼叫附帶的函數呼叫參數是 1，接著我們 Mock 它的回應為前面所建立的測試資料 $user。同時我們還 Mock 了 PostRepository 這個類別，並且補捉 getPostsByUserId() 的 1次性函數呼叫，且此呼叫附帶的函數呼叫參數是 1，接著我們 Mock 它的回應為空陣列 []。
以上就是今天的回顧，希望有讓大家更了解 Mocking 的實際作法。
另外值得一題的是，這4個函數也算是一種 Assertion 函數，因此在跑完測試後，顯示的測試 Assertion 數，是有包含這幾個函數被執行的次數的。
下一篇繼續來探討 Mocking。
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