public void TestBasicLazyCache()
{
// Setting a cell and a cache depending on that cell
var cell = new Cell <int>(2);
var count = 0;
var cache = new LazyCache <int>(() =>
{
count++;
return(cell.Value * 2);
});
Assert.IsFalse(cache.IsCached);
Assert.IsFalse(cache.IsSet);
Assert.AreEqual(0, count);
Assert.AreEqual(0, cache.BeaconCount);
// Reading the value for the first time loads the cache
var value = cache.Value;
Assert.AreEqual(4, value);
Assert.IsTrue(cache.IsCached);
Assert.IsFalse(cache.IsSet);
Assert.AreEqual(1, count);
Assert.AreEqual(1, cache.BeaconCount);
// Reading the value again doesn't trigger a recalculation
value = cache.Value;
Assert.AreEqual(4, value);
Assert.IsTrue(cache.IsCached);
Assert.IsFalse(cache.IsSet);
Assert.AreEqual(1, count);
Assert.AreEqual(1, cache.BeaconCount);
// If we change the cell, the cache reverts back to the initial state
cell.Value = 3;
Assert.IsFalse(cache.IsCached);
Assert.IsFalse(cache.IsSet);
Assert.AreEqual(1, count);
Assert.AreEqual(0, cache.BeaconCount);
// Reading the value again causes the callback to be rerun
value = cache.Value;
Assert.IsTrue(cache.IsCached);
Assert.AreEqual(2, count);
Assert.AreEqual(6, value);
Assert.AreEqual(1, cache.BeaconCount);
// Setting the cache cuts all dependencies
cache.Value = 28;
Assert.IsTrue(cache.IsCached);
Assert.IsTrue(cache.IsSet);
Assert.AreEqual(28, cache.Value);
Assert.AreEqual(0, cache.BeaconCount);
// This time, no dependencies on cell
cell.Value++;
Assert.AreEqual(28, cache.Value);
// If we clear the cache, we revert back to the original state
cache.Clear();
Assert.IsFalse(cache.IsCached);
Assert.IsFalse(cache.IsSet);
Assert.AreEqual(0, cache.BeaconCount);
// Now we re-read the value again
value = cache.Value;
Assert.IsTrue(cache.IsCached);
Assert.AreEqual(3, count);
Assert.AreEqual(8, value);
Assert.AreEqual(1, cache.BeaconCount);
}
public void TestCascadingLazyCache()
{
// We set one cell and two caches in cascade
var cell = new Cell <int>(2);
var cache1 = new LazyCache <int>(() => cell.Value + 1);
var cache2 = new LazyCache <int>(() => cache1.Value * 2);
Assert.IsFalse(cache1.IsCached);
Assert.AreEqual(0, cache1.BeaconCount);
Assert.IsFalse(cache2.IsCached);
Assert.AreEqual(0, cache2.BeaconCount);
// Getting the value of cache number 2
var value = cache2.Value;
Assert.IsTrue(cache1.IsCached);
Assert.AreEqual(1, cache1.BeaconCount);
Assert.IsTrue(cache2.IsCached);
Assert.AreEqual(1, cache2.BeaconCount);
// Checking that setting the base cell invalidate all caches
cell.Value = 3;
Assert.IsFalse(cache1.IsCached);
Assert.AreEqual(0, cache1.BeaconCount);
Assert.IsFalse(cache2.IsCached);
Assert.AreEqual(0, cache2.BeaconCount);
// Querying the value of cache1
value = cache1.Value;
Assert.IsTrue(cache1.IsCached);
Assert.AreEqual(1, cache1.BeaconCount);
Assert.AreEqual(4, value);
Assert.IsFalse(cache2.IsCached);
Assert.AreEqual(0, cache2.BeaconCount);
// Get the value of cache2 now
value = cache2.Value;
Assert.IsTrue(cache1.IsCached);
Assert.AreEqual(1, cache1.BeaconCount);
Assert.IsTrue(cache2.IsCached);
Assert.AreEqual(1, cache2.BeaconCount);
Assert.AreEqual(8, value);
// Set cache1 to an arbitrary value. This should invalidate the cache2
cache1.Value = 34;
Assert.IsTrue(cache1.IsCached);
Assert.IsFalse(cache2.IsCached);
Assert.AreEqual(0, cache1.BeaconCount);
Assert.AreEqual(0, cache2.BeaconCount);
// Get the value of cache2
value = cache2.Value;
Assert.IsTrue(cache1.IsCached);
Assert.IsTrue(cache2.IsCached);
Assert.AreEqual(0, cache1.BeaconCount);
Assert.AreEqual(1, cache2.BeaconCount);
Assert.AreEqual(68, value);
// Setting the cell to a different value should have no impact
cell.Value++;
Assert.IsTrue(cache1.IsCached);
Assert.IsTrue(cache2.IsCached);
Assert.AreEqual(0, cache1.BeaconCount);
Assert.AreEqual(1, cache2.BeaconCount);
Assert.AreEqual(68, cache2.Value);
// Clearing the cache1 should invalidate cache2
cache1.Clear();
Assert.IsFalse(cache1.IsCached);
Assert.AreEqual(0, cache1.BeaconCount);
Assert.IsFalse(cache2.IsCached);
Assert.AreEqual(0, cache2.BeaconCount);
// The value of cache2 should be different now
value = cache2.Value;
Assert.IsTrue(cache1.IsCached);
Assert.IsTrue(cache2.IsCached);
Assert.AreEqual(1, cache1.BeaconCount);
Assert.AreEqual(1, cache2.BeaconCount);
Assert.AreEqual(10, value);
}