Writing your own test doubles

Adam Wathan posted another excellent article on testing on his blog. This time he talks about creating test doubles. Adam demonstrates that creating your own fake can result in a much more readable test than using mocks or spies.

You'll learn to create an InMemoryMailer like this:

public function test_new_users_are_sent_a_welcome_email()
{
    $mailer = new InMemoryMailer;
    Mail::swap($mailer);

    $this->post('register', [
        'name' => 'John Doe',
        'email' => 'john@example.com',
        'password' => 'secret',
    ]);

    $this->assertTrue($mailer->hasMessageFor('john@example.com'));
    $this->assertTrue($mailer->hasMessageWithSubject('Welcome to my app!'));
}

That seems like a pretty readable test to me. Read (or view) the whole tutorial here: http://adamwathan.me/2016/01/25/writing-your-own-test-doubles/

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