Returning attributes through GetAttributeValue in certain error scenarios

[13ajay]

For the C_GetAttributeValue function, the standard states the following:

Note that the error codes CKR_ATTRIBUTE_SENSITIVE, CKR_ATTRIBUTE_TYPE_INVALID, and CKR_BUFFER_TOO_SMALL do not denote true errors for C_GetAttributeValue. If a call to C_GetAttributeValue returns any of these three values, then the call MUST nonetheless have processed every attribute in the template supplied to C_GetAttributeValue. Each attribute in the template whose value can be returned by the call to C_GetAttributeValue will be returned by the call to C_GetAttributeValue.

But based on my reading of the implementation of the wrapper function in this package, regardless of the type of error that is thrown by the C function, if there is one thrown, then the first value returned by GetAttributeValue will be nil. Is my understanding here correct? If so, is that expected? If this package aims to be an implementation of the PKCS#11 API, I think it would be best if it stuck to the standard here.