sometimes missing purchase candidates aren't created

[metas-ts]

Is this a bug or feature request?

Bug

What is the current behavior?

Which are the steps to reproduce?

What is the expected or desired behavior?

[metas-dh]

Results of IT1
tested in mf15

1. Set 2 products A & B with a current vendor, have a discount schema for this vendor
2. Create a sales order, and have orderlines for the 2 products
3. Select all orderlines, and open overlay for creating purchase candidates:

• set a qty to order in purchase for 1 product A (partial qty!)
• don't set a qty for the other product B
  => OK

4. Check purchase candidates: candidate created for product A, none for B: OK
5. Go back to sales order, and create a purchase candidate for product B (partial qty!)
6. Check purchase candidates: additional candidate for product B: OK
7. Go back once to sales order, more and change the qty for the purchase candidate of e.g. product A, in the overlay
8. Check purchase candidates again: purchase candidates for both products, with qties as set / updated: OK
9. Complete the sales order, and check purchase candidates / purchase orders:

• purchase candidates marked as ordered: OK
• purchase order created with orderlines for both products: OK
• qties are as set / updated in the overlay: OK