Stock management - Multistore PS 1.7.5.1

[Bill Dalton]

In Multistore Set "Share available quantities to sell" =>YES

Go to Catalog > Stocks
In All Shops context you receive notification,
"You can't manage your stock in this shop context: select a shop instead of a group of shops."

All stores are now set to share inventory, the ONLY way to manage inventory should be In the context of "All Shops" because it no longer make sense to edit inventory by store context, inventory is now stored in database without shop assignment.

But it gets worse,

In combination bulk edits it will not allow to add inventory in “All Shops” context, again the only way to add inventory is to choose a store. If you try to add inventory with combination bulk edits it will throw error.

This seems related to
[BOOM-5372] Can't create combinations on the second shop if multistore #9664
#9664 (comment)

Additionnal information
PrestaShop version: 1.5.7.1

 

Additional info.

As mentioned trying to add or update stock quantity with All Shops” context ends with error.

Switching to single shop context allows stock addition without error flag, however very nasty error is entered into Table: ps_stock_available

Here is image showing clean/empty table before using combination bulk edit in single store context:

 

Here is image about to add 100 to sample product "1",

 

Update is reported as successful, however see final image of Table: ps_stock_available

1. All stock is assigned to id_shop_qroup > 1
   All stock is set to be shared so it should not be assigned to a shop group.

2. Nasty bug, see field id_stock_available > 308
   No value assigned to id_product_attribute
   COMPLETELY WRONG quantity "800" where did that come from?

3.