Inspect the response in Laravel PHPUnit tests

The Problem

Sometimes, when running integration tests using Laravel and PHPUnit, it’s useful to inspect the response when you can’t figure out why the test is failing. In Laravel 5 and later versions, testing has been highly improved with an API that allows nice and fluent interaction with your application.

Inspect the Response Object

In Laravel, each Test extends the default abstract TestCase class defined in Illuminate\Foundation\Testing. This class uses the CrawlerTrait to provide iteraction with the application, therefore it contains the $response property, which is an instance of \Illuminate\Http\Response and contains the last response returned by the application.

For this reason we can use the getContent() method on the response object to check what the application actually returned. In the following example we are first creating a new user in the database, then we use the chainable API to interact with the application. Finally we use the dd function to dump the variable and stop the execution of the script:

<?php

/** @test */
public function user_can_successfully_login()
{
    $user = factory(App\User::class)->create([ 'password' => 'password' ]);

    $this->visit('/login')
        ->type($user->email, 'email')
        ->type('password', 'password')
        ->press('submit')
        ->seePageIs('/');

    dd($this->response->getContent());
}

If you look carefully, the CrawlerTrait offers a nice shortcut to achieve the same result, so instead of dd($this->response->getContent()) you can simply use $this->dump().

For the curious out there, here is its implementation:

<?php

public function dump()
{
    $content = $this->response->getContent();

    $json = json_decode($content);

    if (json_last_error() === JSON_ERROR_NONE) {
        $content = $json;
    }

    dd($content);
}

Update (10 November 2018)

The dump() function has been removed from the TestCase class since Laravel 5.4, but you can use the one provided by the TestResponse class. (See Api Reference)

Inspect the Session Object

On the other hand, if you want to inspect the Session object after a response, for example if you are looking for validation errors, you can use the following instruction:

<?php

dd($this->app['session.store']);