internal Base Deserialize(ClassMapping mapping, Base existing = null)
{
var mappingToUse = mapping;
if (mappingToUse == null)
{
if (_current.InstanceType is null)
{
throw Error.Format("Underlying data source was not able to provide the actual instance type of the resource.");
}
mappingToUse = (ClassMapping)_inspector.Provide(_current.InstanceType);
if (mappingToUse == null)
{
RaiseFormatError($"Asked to deserialize unknown type '{_current.InstanceType}'", _current.Location);
}
}
if (existing == null)
{
var fac = new DefaultModelFactory();
existing = (Base)fac.Create(mappingToUse.NativeType);
}
else
{
if (mappingToUse.NativeType != existing.GetType())
{
throw Error.Argument(nameof(existing), "Existing instance is of type {0}, but data indicates resource is a {1}".FormatWith(existing.GetType().Name, mappingToUse.NativeType.Name));
}
}
// The older code for read() assumes the primitive value member is represented as a separate child element named "value",
// while the newer ITypedElement represents this as a special Value property. We simulate the old behaviour here, by
// explicitly adding the value property as a child and making it act like a typed node.
var members = _current.Value != null ?
new[] { new ValuePropertyTypedElement(_current) }.Union(_current.Children()) : _current.Children();
read(mappingToUse, members, existing);
return(existing);
}
