No reconcilation of USD invoice with currency difference between invoice and payment date [account_invoice_cash_discount]

[Thorsten Vocks (OpenBig.org)]

Use Case:

To be able to follow the use case:

* We need a bank journal with "USD" as currency.
* We change currency rate between "invoice date" and "payment date" (with bank statement)
* We create a situation (use case) where we have following USD currency rate (in comparition to EUR):

1. 01/01/2010 = 1.3785
2. 09/01/2010 = 1.2500

Invoice date is 08/30/2010 with currency exchange rate of 1.3785. Payment date is today (09/15/2010) with currency rate
of 1.2500.

* We enter a supplier invoice with currency "USD".
* Total amount of invoice (no taxes or anything else in this use case) = 1000 USD => 725.42 EUR (in dependency of invoice date)
* On the day of payment which is today (09/15/2010) rate would be in the second line of rates above (1.2500). We have to pay in USD 1000, which is 1000 USD / current Euro course 1.25 = 800 EUR.

In case of currency rate goes down we have a currency loss situation because we have to pay more (800.00 - 725.42 = 74.58) in EUR for supplier invoice
on payment date in comparation to currency conversion on invoice date. We need account move on the currency (expense) account to reflect this
loss situation.

The statement line and the detail looks like the atached screenshot, which is not right result.

[Thorsten Vocks (OpenBig.org) (openbig.org)]

Next step is confirmation with no change of proposal for reconcilation. The account move which is wrong is visible
in attached screenshot.

[Thorsten Vocks (OpenBig.org) (openbig.org)]

The attachment shows the wrong posted account move. In fact we also can see only a partial reconcilation with a difference of
exchange rate difference between invoice and payment date.

[Thorsten Vocks (OpenBig.org) (openbig.org)]

The problem is also good described in this bug report: 639807

The only difference in my use case. I didn`t click on "Import Invoice", which seems to be only for customer invoices.
Instead i entered the invoice by hand in the first line of payment lines.

[Thomas Dreiling (thomas-dreiling)]

Concerning Thorsten's last comment, I have to object. I tried in a standard OpenERP installation and I could import supplier invoices without any problems. The amount correctly showed -1000 USD/ -800 EUR. We will not accept having to enter supplier invoices manually in the statement.
Additionally, the lines for the exchange rate correction must not have the invoice amount in their foreign currency field. The fields
must be filled but always with a value of 0.00!