[FIXED] Unit Test Laravel's FormRequest

Issue

I am trying to unit test various custom FormRequest inputs. I found solutions that:

1. Suggest using the $this->call(…) method and assert the response with the expected value (link to answer). This is overkill, because it creates a direct dependency on Routing and Controllers.

2. Taylor’s test, from the Laravel Framework found in tests/Foundation/FoundationFormRequestTest.php. There is a lot of mocking and overhead done there.

I am looking for a solution where I can unit test individual field inputs against the rules (independent of other fields in the same request).

Sample FormRequest:

public function rules()
{
    return [
        'first_name' => 'required|between:2,50|alpha',
        'last_name'  => 'required|between:2,50|alpha',
        'email'      => 'required|email|unique:users,email',
        'username'   => 'required|between:6,50|alpha_num|unique:users,username',
        'password'   => 'required|between:8,50|alpha_num|confirmed',
    ];
}

Desired Test:

public function testFirstNameField()
{
   // assertFalse, required
   // ...

   // assertTrue, required
   // ...

   // assertFalse, between
   // ...
}

public function testLastNameField()
{
    // ...
}

How can I unit test (assert) each validation rule of every field in isolation and individually?

Solution

I found a good solution on Laracast and added some customization to the mix.

The Code

/**
 * Test first_name validation rules
 * 
 * @return void
 */
public function test_valid_first_name()
{
    $this->assertTrue($this->validateField('first_name', 'jon'));
    $this->assertTrue($this->validateField('first_name', 'jo'));
    $this->assertFalse($this->validateField('first_name', 'j'));
    $this->assertFalse($this->validateField('first_name', ''));
    $this->assertFalse($this->validateField('first_name', '1'));
    $this->assertFalse($this->validateField('first_name', 'jon1'));
}

/**
 * Check a field and value against validation rule
 * 
 * @param string $field
 * @param mixed $value
 * @return bool
 */
protected function validateField(string $field, $value): bool
{
    return $this->validator->make(
        [$field => $value],
        [$field => $this->rules[$field]]
    )->passes();
}

/**
 * Set up operations
 * 
 * @return void
 */
public function setUp(): void
{
    parent::setUp();

    $this->rules     = (new UserStoreRequest())->rules();
    $this->validator = $this->app['validator'];
}

Update

There is an e2e approach to the same problem. You can POST the data to be checked to the route in question and then see if the response contains session errors.

$response = $this->json('POST', 
    '/route_in_question', 
    ['first_name' => 'S']
);
$response->assertSessionHasErrors(['first_name']);

Answered By - Dov Benyomin Sohacheski