PSR-6 Pool::resolveItem() Testing Example

psr-6-testing-example.php

<?php

class MyClass
{
    private $pool;
    public function __construct(CacheItemPoolInterface $pool) { $this->pool = $pool; }

    public function getDataA($param)
    {
        return $this->pool->resolveItem(
            'item-key',
            function () use ($param) { return resultOfComputation($param); },
            function ($item)         { $item->expiresAfter(300);           }
        )->get();
    }

    public function getDataB($param)
    {
        $item = $this->pool->getItem('item-key');

        if (!$item->isHit()) {
            $item->set(resultOfComputation($param));
            $item->expiresAfter(300);
            $this->pool->save($item);
        }

        return $item->get();
    }
}

class MyClassTest extends PHPUnit_Framework_TestCase
{
    public function testGetDataA()
    {
        $param = 'jim';
        $expectedResult = 'bob';

        $item = $this->getMock('...');
        $item->expects($this->once())->method('expiresAfter')->with(300);
        $item->expects($this->once())->method('get')->willReturn('foobar');

        $pool = $this->getMock('...');
        $pool
            ->expects($this->once())
            ->method('resolveItem')
            ->returnCallback(function($key, $valueCallback, $metaCallback) use ($item, $expectedResult) {
                $this->assertEquals('item-key', $key);
                $this->assertEquals($expectedResult, call_user_func($valueCallback));
                call_user_func($metaCallback, $item);
                return $item;
            });

        $object = new MyClass($pool);
        $this->assertEquals('foobar', $object->getDataA($param));
    }

    public function testGetDataB()
    {
        $param = 'jim';
        $expectedResult = 'bob';

        $hitItem = $this->getMock('...');
        $hitItem->expects($this->once())->method('isHit')->willReturn(true);
        $hitItem->expects($this->once())->method('get')->willReturn('foobarhit');

        $hitPool = $this->getMock('...');
        $hitPool->expects($this->once())->method('getItem')->with('item-key')->willReturn($hitItem);

        $hitObject = new MyClass($hitPool);
        $this->assertEquals('foobarhit', $hitObject->getDataB($param));

        $missItem = $this->getMock('...');
        $missItem->expects($this->once())->method('isHit')->willReturn(false);
        $missItem->expects($this->once())->method('set')->with($expectedResult);
        $missItem->expects($this->once())->method('expiresAfter')->with(300);
        $missItem->expects($this->once())->method('get')->willReturn('foobarmiss');

        $missPool = $this->getMock('...');
        $missPool->expects($this->once())->method('getItem')->with('item-key')->willReturn($missItem);
        $missPool->expects($this->once())->method('save')->with($missItem);

        $missObject = new MyClass($missPool);
        $this->assertEquals('foobarmiss', $missObject->getDataB($param));
    }
}