fix: negative valuation rate in PR return (backport #37424) (backport #37462) (#37463)

fix: negative valuation rate in PR return (backport #37424) (#37462)

* fix: negative valuation rate in PR return (#37424)

* fix: negative valuation rate in PR return

* test: add test case for PR return

(cherry picked from commit 26ad688584)

# Conflicts:
#	erpnext/stock/doctype/purchase_receipt/test_purchase_receipt.py

* chore: `conflicts`

---------

Co-authored-by: s-aga-r <sagarsharma.s312@gmail.com>
(cherry picked from commit 66ad823417)

Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

erpnext/controllers/buying_controller.py

@@ -14,7 +14,8 @@ from erpnext.controllers.sales_and_purchase_return import get_rate_for_return
 from erpnext.controllers.stock_controller import StockController
 from erpnext.controllers.subcontracting import Subcontracting
 from erpnext.stock.get_item_details import get_conversion_factor
-from erpnext.stock.utils import get_incoming_rate
+from erpnext.stock.stock_ledger import get_previous_sle
+from erpnext.stock.utils import get_incoming_rate, get_valuation_method
 
 
 class QtyMismatchError(ValidationError):
@@ -504,9 +505,20 @@ class BuyingController(StockController, Subcontracting):
 					)
 
 					if self.is_return:
-						outgoing_rate = get_rate_for_return(
-							self.doctype, self.name, d.item_code, self.return_against, item_row=d
-						)
+						if get_valuation_method(d.item_code) == "Moving Average":
+							previous_sle = get_previous_sle(
+								{
+									"item_code": d.item_code,
+									"warehouse": d.warehouse,
+									"posting_date": self.posting_date,
+									"posting_time": self.posting_time,
+								}
+							)
+							outgoing_rate = flt(previous_sle.get("valuation_rate"))
+						else:
+							outgoing_rate = get_rate_for_return(
+								self.doctype, self.name, d.item_code, self.return_against, item_row=d
+							)
 
 						sle.update({"outgoing_rate": outgoing_rate, "recalculate_rate": 1})
 						if d.from_warehouse:

erpnext/stock/doctype/purchase_receipt/test_purchase_receipt.py

@@ -1996,6 +1996,60 @@ class TestPurchaseReceipt(FrappeTestCase):
 		ste7.reload()
 		self.assertEqual(ste7.items[0].valuation_rate, valuation_rate)
 
+	def test_valuation_rate_in_return_purchase_receipt_for_moving_average(self):
+		from erpnext.stock.doctype.stock_entry.test_stock_entry import make_stock_entry
+		from erpnext.stock.stock_ledger import get_previous_sle
+
+		# Step - 1: Create an Item (Valuation Method = Moving Average)
+		item_code = make_item(properties={"is_stock_item": 1, "valuation_method": "Moving Average"}).name
+
+		# Step - 2: Create a Purchase Receipt (Qty = 10, Rate = 100)
+		pr = make_purchase_receipt(qty=10, rate=100, item_code=item_code)
+
+		# Step - 3: Create a Material Receipt Stock Entry (Qty = 100, Basic Rate = 10)
+		warehouse = "_Test Warehouse - _TC"
+		make_stock_entry(
+			purpose="Material Receipt",
+			item_code=item_code,
+			to_warehouse=warehouse,
+			qty=100,
+			rate=10,
+		)
+
+		# Step - 4: Create a Material Issue Stock Entry (Qty = 100, Basic Rate = 18.18 [Auto Fetched])
+		make_stock_entry(
+			purpose="Material Issue", item_code=item_code, from_warehouse=warehouse, qty=100
+		)
+
+		# Step - 5: Create a Return Purchase Return (Qty = -8, Rate = 100 [Auto fetched])
+		return_pr = make_purchase_receipt(
+			is_return=1,
+			return_against=pr.name,
+			item_code=item_code,
+			qty=-8,
+		)
+
+		sle = frappe.db.get_value(
+			"Stock Ledger Entry",
+			{"voucher_no": return_pr.name, "voucher_detail_no": return_pr.items[0].name},
+			["posting_date", "posting_time", "outgoing_rate", "valuation_rate"],
+			as_dict=1,
+		)
+		previous_sle_valuation_rate = get_previous_sle(
+			{
+				"item_code": item_code,
+				"warehouse": warehouse,
+				"posting_date": sle.posting_date,
+				"posting_time": sle.posting_time,
+			}
+		).get("valuation_rate")
+
+		# Test - 1: Valuation Rate should be equal to Outgoing Rate
+		self.assertEqual(flt(sle.outgoing_rate, 2), flt(sle.valuation_rate, 2))
+
+		# Test - 2: Valuation Rate should be equal to Previous SLE Valuation Rate
+		self.assertEqual(flt(sle.valuation_rate, 2), flt(previous_sle_valuation_rate, 2))
+
 
 def prepare_data_for_internal_transfer():
 	from erpnext.accounts.doctype.sales_invoice.test_sales_invoice import create_internal_supplier

erpnext/stock/stock_ledger.py

@@ -658,14 +658,16 @@ class update_entries_after(object):
 					get_rate_for_return,  # don't move this import to top
 				)
 
-				rate = get_rate_for_return(
-					sle.voucher_type,
-					sle.voucher_no,
-					sle.item_code,
-					voucher_detail_no=sle.voucher_detail_no,
-					sle=sle,
-				)
-
+				if self.valuation_method == "Moving Average":
+					rate = self.data[self.args.warehouse].previous_sle.valuation_rate
+				else:
+					rate = get_rate_for_return(
+						sle.voucher_type,
+						sle.voucher_no,
+						sle.item_code,
+						voucher_detail_no=sle.voucher_detail_no,
+						sle=sle,
+					)
 			elif (
 				sle.voucher_type in ["Purchase Receipt", "Purchase Invoice"]
 				and sle.voucher_detail_no