public void SimpleTest()
{
using var def = new LifetimeDefinition();
var lifetime = def.Lifetime;
var prop = new WriteOnceProperty <int>();
Assert.Throws <InvalidOperationException>(() => { var _ = prop.Value; });
var v1 = 0;
prop.Advise(lifetime, value => v1 = value);
Assert.AreEqual(0, v1);
Assert.IsFalse(prop.Maybe.HasValue);
Assert.IsTrue(prop.SetIfEmpty(1));
Assert.AreEqual(1, v1);
Assert.AreEqual(1, prop.Value);
Assert.IsFalse(prop.SetIfEmpty(2));
Assert.AreEqual(1, v1);
Assert.AreEqual(1, prop.Value);
Assert.Throws <InvalidOperationException>(() => prop.Value = 2);
Assert.AreEqual(1, v1);
Assert.AreEqual(1, prop.Value);
var v3 = 0;
prop.Advise(lifetime, value => v3 = value);
Assert.AreEqual(1, v1);
Assert.AreEqual(1, v3);
Assert.AreEqual(1, prop.Value);
Assert.AreEqual(1, v1);
Assert.AreEqual(1, v3);
Assert.AreEqual(1, prop.Value);
prop.fireInternal(3);
Assert.AreEqual(1, v1);
Assert.AreEqual(1, v3);
Assert.AreEqual(1, prop.Value);
}
public void ConcurrentWriteAndAdviseTest()
{
const int threadsCount = 10;
for (int i = 0; i < 200; i++)
{
using var def = new LifetimeDefinition();
var lifetime = def.Lifetime;
var prop = new WriteOnceProperty <int>();
var value1 = new AtomicValue();
var count = 0;
var tasks = Enumerable.Range(0, threadsCount).Select(j => Task.Factory.StartNew(() =>
{
Interlocked.Increment(ref count);
SpinWait.SpinUntil(() => Memory.VolatileRead(ref count) == threadsCount); // sync threads
if (!prop.SetIfEmpty(j))
{
return;
}
if (!value1.SetIfDefault(j))
{
Assert.Fail("Value must be written once");
}
}, lifetime)).ToArray();
var values = Enumerable.Range(0, i).Select(j =>
{
var localValue = new AtomicValue();
prop.Advise(lifetime, v =>
{
if (!localValue.SetIfDefault(v))
{
Assert.Fail("Handled must not be called twice");
}
});
return(localValue);
}).ToArray();
Assert.IsTrue(Task.WaitAll(tasks, TimeSpan.FromMinutes(1)), "Task.WaitAll(tasks, TimeSpan.FromMinutes(1))");
value1.AssertNonDefault();
if (values.Length != 0)
{
var value = values.Select(x => x.Value).Distinct().Single();
Assert.AreEqual(value, value1.Value);
}
Assert.AreEqual(value1.Value, prop.Value);
prop.fireInternal(10000);
}
}