[GNC] Evil Lots Behavior

[David T.]

Hello, 

In the course of catching up with my accounting, I've been working extensively with mutual fund holdings, and their buys and sells. I have found a disturbing bug in the way that the lots feature handles existing gains. 

Specifically, the software recalculates ALL gains in a lot the moment you select that lot. A user does not have to try and change anything in the lot; the mere act of selecting the lot causes every gain entry to be recalculated. The recalculation silently takes place without notice to the user, and it recalculates gains entries that have already been reconciled. Sometimes, the value on the reconciled gain transaction will be changed; at other times, new gains entries get created. I haven't figured out why a new entry is created sometimes, and the existing entry gets changed at others. 

This is highly problematic. It means that users cannot rely on lot-managed accounts having accurate gains information, and its silent action means that the user will not know why their accounts were accurate at one point, but not later on. 

To see this in action, create a mutual fund account, add a purchase of 100 shares. Sell 25 shares at a different price, and then use the lots features to assign the purchase and then the sale to a lot. Gnucash will automatically create the gain transaction. Now, change the gain value in the transaction to something else. Reconcile the account, including the gains entry. Now, return to the lot window and select the lot. The gains will be recalculated-- even though the gain is already reconciled. 

If others confirm my observations, I'll file a bug. 

David T.