I implemented the steps provided here to implement GST
I found a bug and am describing the process in a Purchase Order while it exists in Purchase Inv, Sales Invoice and Order as well
Based on these steps provided above the “Purchase Taxes and Charges Template” field populates automatically when the page loads.
When the user selects an Item, from its Item Master, all 3 taxes ie CGST, SGST and IGST are fetched and populates “Purchase Taxes and Charges” table.
Loading of this item taxes overwrites the taxes that were filled with “Purchase Taxes and Charges Template”
In order to correct this the “Purchase Taxes and Charges Template” have to be reselected in that field from that dropdown.
This behaviour is not desirable as a user will assume that the “Purchase Taxes and Charges Template” will have effect if it is filled although its effect is already overwritten.
It becomes even more undesirable when a PO is converted to a purchase invoice. Inspite of “Purchase Taxes and Charges Template” being carried over from the purchase order, the “Purchase Taxes and Charges” table does contain all three taxes fetching them from the Item Master.
A possible solution is the form should refresh the “Purchase Taxes and Charges” table based on content present in “Purchase Taxes and Charges Template” when it is saved.