public void DiscoveredDevice_IsExpired_ImmediatelyReportsTrueIfCacheLifetimeIsZero()
        {
            var discoveredDevice = new DiscoveredSsdpDevice();
            discoveredDevice.AsAt = DateTimeOffset.Now;
            discoveredDevice.CacheLifetime = TimeSpan.Zero;

            Assert.IsTrue(discoveredDevice.IsExpired());
        }
        public void DiscoveredDevice_IsExpired_ReportsTrueAfterCacheLifetimeExpires()
        {
            var discoveredDevice = new DiscoveredSsdpDevice();
            discoveredDevice.AsAt = DateTimeOffset.Now;
            discoveredDevice.CacheLifetime = TimeSpan.FromMilliseconds(100);
            System.Threading.Thread.Sleep(500);

            Assert.IsTrue(discoveredDevice.IsExpired());
        }
        public void DiscoveredDevice_IsExpired_DoesNotImmediatelyReportTrue()
        {
            var discoveredDevice = new DiscoveredSsdpDevice();
            discoveredDevice.AsAt = DateTimeOffset.Now;
            discoveredDevice.CacheLifetime = TimeSpan.FromSeconds(1);

            Assert.IsFalse(discoveredDevice.IsExpired());
        }