Fixed error when a Purchase order is voided

[yamelsenih]

Step by Step

• Create a Purchase Order
• Create a Receipt from Purchase Order
• Void the PO

What is wrong?

When the PO is voided, the MM Receipt is completed and exist a deadlock

The PR just add a validation for PO when is void for verify if exist a
receipt.

See the message:

Note: when a PO is based on Warehouse Order the receipt are
automatically reversed

Please merge it with squash

[marcalwestf]

hi @yamelsenih Yamel,

The code seems OK. It makes sure that a Purchase Order cannot be voided if there has been already a material receipt.
The quantities delivered (reserved also?) can be left in an improper state if allowing the voiding.

My problem is that I could not reproduce the error:

Trial I

• create and complete a Purchase Order
• create and complete a Material Receipt based on the Purchase Order
• Void the Order -> no error produced
  
  

Trial II

• create and complete a Purchase Order
• create Material Receipt based on the Purchase Order, leave it in the drafted mode
• Void the Order -> no error produced
  
  

Perhaps I am missing something?
I mean, even without reproducing the error this PR is worth being accepted, but nevertheless, it would be interesting to know why there is a table lock on your development environment but non on mine.