Merge pull request #35061 from ruthra-kumar/refactor_pe_dont_book_gain_loss_for_sales_purchase_orders

refactor: don't book exchange gain/loss for sales/purchase orders

erpnext/accounts/doctype/payment_entry/payment_entry.py

@@ -654,6 +654,28 @@ class PaymentEntry(AccountsController):
 				self.precision("base_received_amount"),
 			)
 
+	def calculate_base_allocated_amount_for_reference(self, d) -> float:
+		base_allocated_amount = 0
+		if d.reference_doctype in frappe.get_hooks("advance_payment_doctypes"):
+			# When referencing Sales/Purchase Order, use the source/target exchange rate depending on payment type.
+			# This is so there are no Exchange Gain/Loss generated for such doctypes
+
+			exchange_rate = 1
+			if self.payment_type == "Receive":
+				exchange_rate = self.source_exchange_rate
+			elif self.payment_type == "Pay":
+				exchange_rate = self.target_exchange_rate
+
+			base_allocated_amount += flt(
+				flt(d.allocated_amount) * flt(exchange_rate), self.precision("base_paid_amount")
+			)
+		else:
+			base_allocated_amount += flt(
+				flt(d.allocated_amount) * flt(d.exchange_rate), self.precision("base_paid_amount")
+			)
+
+		return base_allocated_amount
+
 	def set_total_allocated_amount(self):
 		if self.payment_type == "Internal Transfer":
 			return
@@ -662,9 +684,7 @@ class PaymentEntry(AccountsController):
 		for d in self.get("references"):
 			if d.allocated_amount:
 				total_allocated_amount += flt(d.allocated_amount)
-				base_total_allocated_amount += flt(
-					flt(d.allocated_amount) * flt(d.exchange_rate), self.precision("base_paid_amount")
-				)
+				base_total_allocated_amount += self.calculate_base_allocated_amount_for_reference(d)
 
 		self.total_allocated_amount = abs(total_allocated_amount)
 		self.base_total_allocated_amount = abs(base_total_allocated_amount)
@@ -881,9 +901,7 @@ class PaymentEntry(AccountsController):
 					}
 				)
 
-				allocated_amount_in_company_currency = flt(
-					flt(d.allocated_amount) * flt(d.exchange_rate), self.precision("paid_amount")
-				)
+				allocated_amount_in_company_currency = self.calculate_base_allocated_amount_for_reference(d)
 
 				gle.update(
 					{

erpnext/accounts/doctype/payment_entry/test_payment_entry.py

@@ -51,6 +51,38 @@ class TestPaymentEntry(FrappeTestCase):
 		so_advance_paid = frappe.db.get_value("Sales Order", so.name, "advance_paid")
 		self.assertEqual(so_advance_paid, 0)
 
+	def test_payment_against_sales_order_usd_to_inr(self):
+		so = make_sales_order(
+			customer="_Test Customer USD", currency="USD", qty=1, rate=100, do_not_submit=True
+		)
+		so.conversion_rate = 50
+		so.submit()
+		pe = get_payment_entry("Sales Order", so.name)
+		pe.source_exchange_rate = 55
+		pe.received_amount = 5500
+		pe.insert()
+		pe.submit()
+
+		# there should be no difference amount
+		pe.reload()
+		self.assertEqual(pe.difference_amount, 0)
+		self.assertEqual(pe.deductions, [])
+
+		expected_gle = dict(
+			(d[0], d)
+			for d in [["_Test Receivable USD - _TC", 0, 5500, so.name], ["Cash - _TC", 5500.0, 0, None]]
+		)
+
+		self.validate_gl_entries(pe.name, expected_gle)
+
+		so_advance_paid = frappe.db.get_value("Sales Order", so.name, "advance_paid")
+		self.assertEqual(so_advance_paid, 100)
+
+		pe.cancel()
+
+		so_advance_paid = frappe.db.get_value("Sales Order", so.name, "advance_paid")
+		self.assertEqual(so_advance_paid, 0)
+
 	def test_payment_entry_for_blocked_supplier_invoice(self):
 		supplier = frappe.get_doc("Supplier", "_Test Supplier")
 		supplier.on_hold = 1