JoinTest.php

<?php

declare(strict_types=1);

namespace BenCondaTest\Collection\Modifier;

use BenConda\Collection\Collection;
use PHPUnit\Framework\TestCase;

/**
 * @covers \BenConda\Collection\Modifier\Join
 */
final class JoinTest extends TestCase
{
    /** @var Collection<int, Item> */
    private Collection $itemCollection;
    /** @var Collection<int, Person> */
    private Collection $personCollection;
    /** @var Collection<int, Cart> */
    private Collection $cartCollection;

    protected function setUp(): void
    {
        $this->itemCollection = Collection::from([
            new Item(0, 'Banana'),
            new Item(1, 'Peach'),
            new Item(2, 'Peanuts'),
        ]);
        $this->personCollection = Collection::from([
            new Person(0, 'Person 1'),
            new Person(1, 'Person 2'),
            new Person(2, 'Person 3'),
        ]);
        $this->cartCollection = Collection::from([
            new Cart(personId: 0, itemId: 0),
            new Cart(personId: 0, itemId: 2),
            new Cart(personId: 0, itemId: 1),
            new Cart(personId: 1, itemId: 1),
        ]);
    }

    public function testMapWithModifier(): void
    {
        $personsWithCartItems = $this->personCollection
            ->join(
                $this->cartCollection,
                on: fn (Person $person, Cart $cart): bool => $person->id === $cart->personId,
                select: fn (Person $person, Collection $cart): PersonWithCartItems => new PersonWithCartItems(
                    $person,
                    $cart->join(
                        $this->itemCollection,
                        on: fn (Cart $cart, Item $item): bool => $cart->itemId === $item->id,
                        select: fn (Cart $cart, Collection $item) => $item->first()
                    )
                ),
            );

        foreach ($personsWithCartItems as $item) {
            self::assertInstanceOf(PersonWithCartItems::class, $item);
            self::assertInstanceOf(Collection::class, $item->cartItems);
            foreach ($item->cartItems as $cartItem) {
                self::assertInstanceOf(Item::class, $cartItem);
            }
        }
    }
}

class Item
{
    public function __construct(
        public readonly int $id,
        public readonly string $name
    ) {
    }
}

class Person
{
    public function __construct(
        public readonly int $id,
        public readonly string $name
    ) {
    }
}

class Cart
{
    public function __construct(
        public readonly int $personId,
        public readonly int $itemId
    ) {
    }
}

class PersonWithCartItems
{
    /**
     * @param List<?Item> $cartItems
     */
    public function __construct(
        public readonly Person $person,
        public readonly iterable $cartItems
    ) {
    }
}