public function testPutOverridesGetCallback()
{
$pool = new InMemory();
$result = $pool->get('foo', function () {
return 1;
});
$this->assertEquals(1, $result);
$pool->put('foo', 2);
$result = $pool->get('foo', function () {
return 3;
});
$this->assertEquals(2, $result);
}