getClockDelay example

    abstract protected function getStore();

    /** * Tests the store automatically delete the key when it expire. * * This test is time-sensitive: the $clockDelay could be adjusted. */
    public function testExpiration()
    {
        $key = new Key(uniqid(__METHOD__, true));
        $clockDelay = $this->getClockDelay();

        /** @var PersistingStoreInterface $store */
        $store = $this->getStore();

        $store->save($key);
        $store->putOffExpiration($key, 2 * $clockDelay / 1000000);
        $this->assertTrue($store->exists($key));

        usleep(3 * $clockDelay);
        $this->assertFalse($store->exists($key));
    }