public void OnDataChange_PerformsCopyOperation()
{
Assert.That(_copyOnWriteData.ToArray(), Is.EqualTo(new[] { _domainObject1, _domainObject2 }));
_copyOnWriteData.Add(_domainObject3);
Assert.That(_copyOnWriteData.ToArray(), Is.EqualTo(new[] { _domainObject1, _domainObject2, _domainObject3 }));
Assert.That(_copiedData.ToArray(), Is.EqualTo(new[] { _domainObject1, _domainObject2 }));
}
/// <summary>
/// Registers the given <paramref name="domainObject"/> as an original item of this collection. This means the item is added to the
/// <see cref="OriginalData"/> collection, and it is also added to this <see cref="ChangeCachingCollectionDataDecorator"/> collection. If the
/// <see cref="OriginalData"/> collection already contains the item, an exception is thrown. If this collection already contains the item, it is
/// only added to the <see cref="OriginalData"/>. This operation may invalidate the state cache.
/// </summary>
/// <param name="domainObject">The <see cref="DomainObject"/> to be registered.</param>
public void RegisterOriginalItem(DomainObject domainObject)
{
ArgumentUtility.CheckNotNull("domainObject", domainObject);
// Original collection must not contain this item
if (_originalData.ContainsObjectID(domainObject.ID))
{
var message = string.Format("The original collection already contains a domain object with ID '{0}'.", domainObject.ID);
throw new InvalidOperationException(message);
}
// Check if this collection does not contain the item
if (!_unobservedWrappedData.ContainsObjectID(domainObject.ID))
{
// Standard case: Neither collection contains the item; the item is added to both, and the state cache stays valid
// Add the item to the unobserved inner collection to avoid copy on write: if the contents hasn't been copied, we want to modify both
// collections at the same time!
// This way, if the original collection has not yet been copied, it will automatically contain the item and the state cache remains valid.
_unobservedWrappedData.Add(domainObject);
// If the original collection has already been copied, we must add the item manually. The state cache still remains valid because we always add
// the item at the end. If the collections were equal before, they remain equal now. If they were different before, they remain different.
if (_originalData.IsContentsCopied)
{
_originalData.Add(domainObject);
}
}
else
{
// Special case: The current collection already contains the item
// We must add the item to the original collection only and raise a potential state change notification
_originalData.Add(domainObject);
OnChangeStateUnclear();
}
Assertion.IsTrue(ContainsObjectID(domainObject.ID));
Assertion.IsTrue(_originalData.ContainsObjectID(domainObject.ID));
}