Test hierarchy with Contexts/Scopes

[thiagovictorino]

I was looking into Pest and its documentation, then I miss a very nice feature.

Summary

Create a feature where it is possible to create contexts inside tests and inside other contexts to apply the idea of test hierarchy, like scoping in Jest and Context in RSpec to run scoped setUp and tearDowns

Example

Let's think about the scenario:

• A system where We have a bank account
• The bank has a default Interest rate
• Every time you create a new account, this interest rate is copied to the account.
• I want to test if the account interest rate keeps even after the bank default interest rate changes and do many tests with this new rate.

class Bank {
   protected int $defaultInterestRate = 1;

   public function setDefaultInterestRate(int $rate) {
     $this->defaultInterestRate = $rate
   }
   
   public function getDefaultInterestRate(): int {
     return $this->defaultInterestRate
   }
}

class Account {
  protected $interestRate;

   function __construct(Bank $bank) {
    $this->interestRate = $bank-> getDefaultInterestRate()
  }
  
  public function getInterestRate(): int {
     return $this->interestRate
  }
}

My suggestion is the test be something like

beforeAll(function () {
    $bank = new Bank;
    $account = new Account($bank);
});

it('should have that same interest rate', function () {
   $this->assertEquals($bank->getDefaultInterestRate(), $account->getInterestRate());
});

// do more tests

context('with the bank interest rate changed', function(){
    beforeAll(function () {
        $bank->setDefaultInterestRate(2)
    });

  it('should have the same old rate', function () {
    $this->assertEquals(1, $account->getInterestRate());
  });
  //do more tests with the bank with a new default interest value
})

I know that I am not using the same architecture as Pest. I am just trying to show my idea.

Why I think it is good to have

Well, when we have a significant setups functions, it can be a problem because sometimes you don't need to run all the functions inside beforeAll or beforeEach, but only when some tests run.

I saw one discussion posted that didn't point out the idea so profoundly.