internal static AssignmentChanges Compute(AssignmentData oldAssignment, AssignmentData newAssignment)
{
Debug.Assert(oldAssignment != newAssignment);
Debug.Assert(oldAssignment.Id == newAssignment.Id);
var result = new List <FieldChange <AssignmentField> >();
foreach (var field in oldAssignment.SetFields)
{
var oldValue = oldAssignment.GetValue(field);
if (!newAssignment.HasValue(field))
{
result.Add(new FieldChange <AssignmentField>(field, oldValue, field.DefaultValue));
}
else
{
var newValue = newAssignment.GetValue(field);
if (!Equals(oldValue, newValue))
{
result.Add(new FieldChange <AssignmentField>(field, oldValue, newValue));
}
}
}
foreach (var field in newAssignment.SetFields)
{
var newValue = newAssignment.GetValue(field);
if (!oldAssignment.HasValue(field))
{
result.Add(new FieldChange <AssignmentField>(field, field.DefaultValue, newValue));
}
}
return(new AssignmentChanges(oldAssignment.Id, result.ToImmutableArray()));
}
public object GetValue(AssignmentField field)
{
return(_data.GetValue(field));
}