refactor: merge taxes from delivery note to Sales Invoice

erpnext/controllers/accounts_controller.py

@@ -3521,6 +3521,37 @@ def check_if_child_table_updated(child_table_before_update, child_table_after_up
 	return False
 
 
+def merge_taxes(source_taxes, target_doc):
+	from erpnext.accounts.doctype.pos_invoice_merge_log.pos_invoice_merge_log import (
+		update_item_wise_tax_detail,
+	)
+
+	existing_taxes = target_doc.get("taxes") or []
+	idx = 1
+	for tax in source_taxes:
+		found = False
+		for t in existing_taxes:
+			if t.account_head == tax.account_head and t.cost_center == tax.cost_center:
+				t.tax_amount = flt(t.tax_amount) + flt(tax.tax_amount_after_discount_amount)
+				t.base_tax_amount = flt(t.base_tax_amount) + flt(tax.base_tax_amount_after_discount_amount)
+				update_item_wise_tax_detail(t, tax)
+				found = True
+
+		if not found:
+			tax.charge_type = "Actual"
+			tax.idx = idx
+			idx += 1
+			tax.included_in_print_rate = 0
+			tax.dont_recompute_tax = 1
+			tax.row_id = ""
+			tax.tax_amount = tax.tax_amount_after_discount_amount
+			tax.base_tax_amount = tax.base_tax_amount_after_discount_amount
+			tax.item_wise_tax_detail = tax.item_wise_tax_detail
+			existing_taxes.append(tax)
+
+	target_doc.set("taxes", existing_taxes)
+
+
 @erpnext.allow_regional
 def validate_regional(doc):
 	pass