KATA: Test your FizzBuzz

• Exercise Summary

Setup your computer

• Download PHP
• Download Composer

Initialize the project

git clone
cd kata-phpunit
composer install
php src/main.php

Do the KATA

Following this exercise summary:

0. clone the repository

1. setup PHPUnit

2. code & test the FizzBuzz inside the FizzBuzz class (src/FizzBuzz.php)

3. create your first mock

execute fizzbuzz inside transformFromDatabase() on an integers list provided by Database::getNumbers(). but.. you cannot change Database::getNumbers(), so mock it!

Add followings files:

• src/DatabaseInterface.php

<?php

namespace App;

interface DatabaseInterface
{
    /**
     * return a list of numbers
     *
     * @return array
     */
    public function getNumbers(): array;
}

• src/Database.php

<?php

namespace App;

class Database implements DatabaseInterface
{
    public function getNumbers(): array
    {
        throw new \Exception("DO NOT IMPLEMENT", 501);
    }
}

Edit followings files:

• src/FizzBuzz.php

class FizzBuzz
{
    public function __construct(protected Database $database) {}

    public function transformFromDatabase(): array
    {
        $numbers = $this->database->getNumbers();

        throw new \Exception('Execute the FizzBuzz on your array of numbers');
    }

• src/main.php

<?php
require './vendor/autoload.php';

use App\Database;
use App\FizzBuzz;

$fizzBuzz = new FizzBuzz();
$fizzBuzz = new FizzBuzz(new Database());

try {
    $lines = $fizzBuzz->countTo100();
    foreach ($lines as $line) {
        echo $line . PHP_EOL;
    }
} catch (Exception $e) {
    echo $e->getMessage();
}

try {
    $lines = $fizzBuzz->transformFromDatabase();
} catch (Exception $e) {
    if (501 === $e->getCode()) {
        echo 'Database::getNumbers() not implemented';
    }
}

4. bonus: do a mock of a database interface that should return a list of Numbers, based on DatabaseInterface

5. bonus: install & use infection

You are stuck in a step ? Checkout stepX branch to get help