fix: purchase invoice return GLe

voucher_wise_stock_value contains tuples and the condition was looking
for string, so it's never triggered.

Caused by https://github.com/frappe/erpnext/pull/24200

erpnext/accounts/doctype/purchase_invoice/purchase_invoice.py

@@ -1127,7 +1127,7 @@ class PurchaseInvoice(BuyingController):
 		# Stock ledger value is not matching with the warehouse amount
 		if (
 			self.update_stock
-			and voucher_wise_stock_value.get(item.name)
+			and voucher_wise_stock_value.get((item.name, item.warehouse))
 			and warehouse_debit_amount
 			!= flt(voucher_wise_stock_value.get((item.name, item.warehouse)), net_amt_precision)
 		):

erpnext/accounts/doctype/purchase_invoice/test_purchase_invoice.py

@@ -27,12 +27,13 @@ from erpnext.stock.doctype.purchase_receipt.test_purchase_receipt import (
 	make_purchase_receipt,
 )
 from erpnext.stock.doctype.stock_entry.test_stock_entry import get_qty_after_transaction
+from erpnext.stock.tests.test_utils import StockTestMixin
 
 test_dependencies = ["Item", "Cost Center", "Payment Term", "Payment Terms Template"]
 test_ignore = ["Serial No"]
 
 
-class TestPurchaseInvoice(unittest.TestCase):
+class TestPurchaseInvoice(unittest.TestCase, StockTestMixin):
 	@classmethod
 	def setUpClass(self):
 		unlink_payment_on_cancel_of_invoice()
@@ -693,6 +694,80 @@ class TestPurchaseInvoice(unittest.TestCase):
 			self.assertEqual(expected_values[gle.account][0], gle.debit)
 			self.assertEqual(expected_values[gle.account][1], gle.credit)
 
+	def test_standalone_return_using_pi(self):
+		from erpnext.stock.doctype.stock_entry.test_stock_entry import make_stock_entry
+
+		item = self.make_item().name
+		company = "_Test Company with perpetual inventory"
+		warehouse = "Stores - TCP1"
+
+		make_stock_entry(item_code=item, target=warehouse, qty=50, rate=120)
+
+		return_pi = make_purchase_invoice(
+			is_return=1,
+			item=item,
+			qty=-10,
+			update_stock=1,
+			rate=100,
+			company=company,
+			warehouse=warehouse,
+			cost_center="Main - TCP1",
+		)
+
+		# assert that stock consumption is with actual rate
+		self.assertGLEs(
+			return_pi,
+			[{"credit": 1200, "debit": 0}],
+			gle_filters={"account": "Stock In Hand - TCP1"},
+		)
+
+		# assert loss booked in COGS
+		self.assertGLEs(
+			return_pi,
+			[{"credit": 0, "debit": 200}],
+			gle_filters={"account": "Cost of Goods Sold - TCP1"},
+		)
+
+	def test_return_with_lcv(self):
+		from erpnext.controllers.sales_and_purchase_return import make_return_doc
+		from erpnext.stock.doctype.landed_cost_voucher.test_landed_cost_voucher import (
+			create_landed_cost_voucher,
+		)
+
+		item = self.make_item().name
+		company = "_Test Company with perpetual inventory"
+		warehouse = "Stores - TCP1"
+		cost_center = "Main - TCP1"
+
+		pi = make_purchase_invoice(
+			item=item,
+			company=company,
+			warehouse=warehouse,
+			cost_center=cost_center,
+			update_stock=1,
+			qty=10,
+			rate=100,
+		)
+
+		# Create landed cost voucher - will increase valuation of received item by 10
+		create_landed_cost_voucher("Purchase Invoice", pi.name, pi.company, charges=100)
+		return_pi = make_return_doc(pi.doctype, pi.name)
+		return_pi.save().submit()
+
+		# assert that stock consumption is with actual in rate
+		self.assertGLEs(
+			return_pi,
+			[{"credit": 1100, "debit": 0}],
+			gle_filters={"account": "Stock In Hand - TCP1"},
+		)
+
+		# assert loss booked in COGS
+		self.assertGLEs(
+			return_pi,
+			[{"credit": 0, "debit": 100}],
+			gle_filters={"account": "Cost of Goods Sold - TCP1"},
+		)
+
 	def test_multi_currency_gle(self):
 		pi = make_purchase_invoice(
 			supplier="_Test Supplier USD",

erpnext/controllers/sales_and_purchase_return.py

@@ -316,7 +316,7 @@ def get_returned_qty_map_for_row(return_against, party, row_name, doctype):
 	return data[0]
 
 
-def make_return_doc(doctype, source_name, target_doc=None):
+def make_return_doc(doctype: str, source_name: str, target_doc=None):
 	from frappe.model.mapper import get_mapped_doc
 
 	from erpnext.stock.doctype.serial_no.serial_no import get_serial_nos

erpnext/stock/tests/test_utils.py

@@ -38,6 +38,23 @@ class StockTestMixin:
 
 				self.assertEqual(v, act_value, msg=f"{k} doesn't match \n{exp_sle}\n{act_sle}")
 
+	def assertGLEs(self, doc, expected_gles, gle_filters=None, order_by=None):
+		filters = {"voucher_no": doc.name, "voucher_type": doc.doctype, "is_cancelled": 0}
+
+		if gle_filters:
+			filters.update(gle_filters)
+		actual_gles = frappe.get_all(
+			"GL Entry",
+			fields=["*"],
+			filters=filters,
+			order_by=order_by or "posting_date, creation",
+		)
+
+		for exp_gle, act_gle in zip(expected_gles, actual_gles):
+			for k, exp_value in exp_gle.items():
+				act_value = act_gle[k]
+				self.assertEqual(exp_value, act_value, msg=f"{k} doesn't match \n{exp_gle}\n{act_gle}")
+
 
 class TestStockUtilities(FrappeTestCase, StockTestMixin):
 	def test_barcode_scanning(self):