feat: get_valuation_rate batch wise

This function is used to show valuation rate on frontend and also as
fallback in case values aren't available. Add "batch_no" param to get
batch specific valuation rates.

Co-Authored-By: Alan Tom <2.alan.tom@gmail.com>

erpnext/controllers/buying_controller.py

@@ -249,6 +249,7 @@ class BuyingController(StockController, Subcontracting):
 						"posting_time": self.get('posting_time'),
 						"qty": -1 * flt(d.get('stock_qty')),
 						"serial_no": d.get('serial_no'),
+						"batch_no": d.get("batch_no"),
 						"company": self.company,
 						"voucher_type": self.doctype,
 						"voucher_no": self.name,

erpnext/controllers/sales_and_purchase_return.py

@@ -420,6 +420,7 @@ def get_rate_for_return(voucher_type, voucher_no, item_code, return_against=None
 				"posting_time": sle.get('posting_time'),
 				"qty": sle.actual_qty,
 				"serial_no": sle.get('serial_no'),
+				"batch_no": sle.get("batch_no"),
 				"company": sle.company,
 				"voucher_type": sle.voucher_type,
 				"voucher_no": sle.voucher_no

erpnext/controllers/selling_controller.py

@@ -394,6 +394,7 @@ class SellingController(StockController):
 						"posting_time": self.get('posting_time') or nowtime(),
 						"qty": qty if cint(self.get("is_return")) else (-1 * qty),
 						"serial_no": d.get('serial_no'),
+						"batch_no": d.get("batch_no"),
 						"company": self.company,
 						"voucher_type": self.doctype,
 						"voucher_no": self.name,

erpnext/public/js/controllers/transaction.js

@@ -719,6 +719,7 @@ erpnext.TransactionController = class TransactionController extends erpnext.taxe
 			'posting_time': posting_time,
 			'qty': item.qty * item.conversion_factor,
 			'serial_no': item.serial_no,
+			'batch_no': item.batch_no,
 			'voucher_type': voucher_type,
 			'company': company,
 			'allow_zero_valuation_rate': item.allow_zero_valuation_rate

erpnext/stock/doctype/batch/test_batch.py

@@ -8,7 +8,11 @@ from frappe.utils import cint, flt
 from erpnext.accounts.doctype.purchase_invoice.test_purchase_invoice import make_purchase_invoice
 from erpnext.stock.doctype.batch.batch import UnableToSelectBatchError, get_batch_no, get_batch_qty
 from erpnext.stock.doctype.stock_entry.stock_entry_utils import make_stock_entry
+from erpnext.stock.doctype.stock_reconciliation.test_stock_reconciliation import (
+	create_stock_reconciliation,
+)
 from erpnext.stock.get_item_details import get_item_details
+from erpnext.stock.stock_ledger import get_valuation_rate
 from erpnext.tests.utils import ERPNextTestCase
 
 
@@ -345,6 +349,41 @@ class TestBatch(ERPNextTestCase):
 
 			self.assertEqual(sle.stock_queue, [])  # queues don't apply on batched items
 
+	def test_moving_batch_valuation_rates(self):
+		item_code = "_TestBatchWiseVal"
+		warehouse = "_Test Warehouse - _TC"
+		self.make_batch_item(item_code)
+
+		def assertValuation(expected):
+			actual = get_valuation_rate(item_code, warehouse, "voucher_type", "voucher_no", batch_no=batch_no)
+			self.assertAlmostEqual(actual, expected)
+
+		se = make_stock_entry(item_code=item_code, qty=100, rate=10, target=warehouse)
+		batch_no = se.items[0].batch_no
+		assertValuation(10)
+
+		# consumption should never affect current valuation rate
+		make_stock_entry(item_code=item_code, qty=20, source=warehouse)
+		assertValuation(10)
+
+		make_stock_entry(item_code=item_code, qty=30, source=warehouse)
+		assertValuation(10)
+
+		# 50 * 10 = 500 current value, add more item with higher valuation
+		make_stock_entry(item_code=item_code, qty=50, rate=20, target=warehouse, batch_no=batch_no)
+		assertValuation(15)
+
+		# consuming again shouldn't do anything
+		make_stock_entry(item_code=item_code, qty=20, source=warehouse)
+		assertValuation(15)
+
+		# reset rate with stock reconiliation
+		create_stock_reconciliation(item_code=item_code, warehouse=warehouse, qty=10, rate=25, batch_no=batch_no)
+		assertValuation(25)
+
+		make_stock_entry(item_code=item_code, qty=20, rate=20, target=warehouse, batch_no=batch_no)
+		assertValuation((20 * 20 + 10 * 25) / (10 + 20))
+
 
 def create_batch(item_code, rate, create_item_price_for_batch):
 	pi = make_purchase_invoice(company="_Test Company",

erpnext/stock/doctype/stock_entry/stock_entry.js

@@ -425,6 +425,7 @@ frappe.ui.form.on('Stock Entry', {
 			'posting_time'		: frm.doc.posting_time,
 			'warehouse'			: cstr(item.s_warehouse) || cstr(item.t_warehouse),
 			'serial_no'			: item.serial_no,
+			'batch_no'          : item.batch_no,
 			'company'			: frm.doc.company,
 			'qty'				: item.s_warehouse ? -1*flt(item.transfer_qty) : flt(item.transfer_qty),
 			'voucher_type'		: frm.doc.doctype,
@@ -457,6 +458,7 @@ frappe.ui.form.on('Stock Entry', {
 						'warehouse': cstr(child.s_warehouse) || cstr(child.t_warehouse),
 						'transfer_qty': child.transfer_qty,
 						'serial_no': child.serial_no,
+						'batch_no': child.batch_no,
 						'qty': child.s_warehouse ? -1* child.transfer_qty : child.transfer_qty,
 						'posting_date': frm.doc.posting_date,
 						'posting_time': frm.doc.posting_time,
@@ -680,6 +682,7 @@ frappe.ui.form.on('Stock Entry Detail', {
 				'warehouse'			: cstr(d.s_warehouse) || cstr(d.t_warehouse),
 				'transfer_qty'		: d.transfer_qty,
 				'serial_no'		: d.serial_no,
+				'batch_no'      : d.batch_no,
 				'bom_no'		: d.bom_no,
 				'expense_account'	: d.expense_account,
 				'cost_center'		: d.cost_center,

erpnext/stock/doctype/stock_entry/stock_entry.py

@@ -510,7 +510,7 @@ class StockEntry(StockController):
 				d.basic_rate = get_valuation_rate(d.item_code, d.t_warehouse,
 					self.doctype, self.name, d.allow_zero_valuation_rate,
 					currency=erpnext.get_company_currency(self.company), company=self.company,
-					raise_error_if_no_rate=raise_error_if_no_rate)
+					raise_error_if_no_rate=raise_error_if_no_rate, batch_no=d.batch_no)
 
 			d.basic_rate = flt(d.basic_rate, d.precision("basic_rate"))
 			if d.is_process_loss:
@@ -541,6 +541,7 @@ class StockEntry(StockController):
 			"posting_time": self.posting_time,
 			"qty": item.s_warehouse and -1*flt(item.transfer_qty) or flt(item.transfer_qty),
 			"serial_no": item.serial_no,
+			"batch_no": item.batch_no,
 			"voucher_type": self.doctype,
 			"voucher_no": self.name,
 			"company": self.company,

erpnext/stock/stock_ledger.py

@@ -634,7 +634,7 @@ class update_entries_after(object):
 			if not allow_zero_rate:
 				self.wh_data.valuation_rate = get_valuation_rate(sle.item_code, sle.warehouse,
 					sle.voucher_type, sle.voucher_no, self.allow_zero_rate,
-					currency=erpnext.get_company_currency(sle.company), company=sle.company)
+					currency=erpnext.get_company_currency(sle.company), company=sle.company, batch_no=sle.batch_no)
 
 	def get_incoming_value_for_serial_nos(self, sle, serial_nos):
 		# get rate from serial nos within same company
@@ -702,7 +702,7 @@ class update_entries_after(object):
 				if not allow_zero_valuation_rate:
 					self.wh_data.valuation_rate = get_valuation_rate(sle.item_code, sle.warehouse,
 						sle.voucher_type, sle.voucher_no, self.allow_zero_rate,
-						currency=erpnext.get_company_currency(sle.company), company=sle.company)
+						currency=erpnext.get_company_currency(sle.company), company=sle.company, batch_no=sle.batch_no)
 
 	def update_queue_values(self, sle):
 		incoming_rate = flt(sle.incoming_rate)
@@ -722,7 +722,7 @@ class update_entries_after(object):
 				if not allow_zero_valuation_rate:
 					return get_valuation_rate(sle.item_code, sle.warehouse,
 						sle.voucher_type, sle.voucher_no, self.allow_zero_rate,
-						currency=erpnext.get_company_currency(sle.company), company=sle.company)
+						currency=erpnext.get_company_currency(sle.company), company=sle.company, batch_no=sle.batch_no)
 				else:
 					return 0.0
 
@@ -950,21 +950,38 @@ def _get_batch_outgoing_rate(item_code, warehouse, batch_no, posting_date, posti
 
 
 def get_valuation_rate(item_code, warehouse, voucher_type, voucher_no,
-	allow_zero_rate=False, currency=None, company=None, raise_error_if_no_rate=True):
+	allow_zero_rate=False, currency=None, company=None, raise_error_if_no_rate=True, batch_no=None):
 
 	if not company:
 		company =  frappe.get_cached_value("Warehouse", warehouse, "company")
 
+	last_valuation_rate = None
+
+	# Get moving average rate of a specific batch number
+	if warehouse and batch_no and frappe.db.get_value("Batch", batch_no, "use_batchwise_valuation"):
+		last_valuation_rate = frappe.db.sql("""
+			select sum(stock_value_difference) / sum(actual_qty)
+			from `tabStock Ledger Entry`
+			where
+				item_code = %s
+				AND warehouse = %s
+				AND batch_no = %s
+				AND is_cancelled = 0
+				AND NOT (voucher_no = %s AND voucher_type = %s)
+			""",
+			(item_code, warehouse, batch_no, voucher_no, voucher_type))
+
 	# Get valuation rate from last sle for the same item and warehouse
-	last_valuation_rate = frappe.db.sql("""select valuation_rate
-		from `tabStock Ledger Entry` force index (item_warehouse)
-		where
-			item_code = %s
-			AND warehouse = %s
-			AND valuation_rate >= 0
-			AND is_cancelled = 0
-			AND NOT (voucher_no = %s AND voucher_type = %s)
-		order by posting_date desc, posting_time desc, name desc limit 1""", (item_code, warehouse, voucher_no, voucher_type))
+	if not last_valuation_rate or last_valuation_rate[0][0] is None:
+		last_valuation_rate = frappe.db.sql("""select valuation_rate
+			from `tabStock Ledger Entry` force index (item_warehouse)
+			where
+				item_code = %s
+				AND warehouse = %s
+				AND valuation_rate >= 0
+				AND is_cancelled = 0
+				AND NOT (voucher_no = %s AND voucher_type = %s)
+			order by posting_date desc, posting_time desc, name desc limit 1""", (item_code, warehouse, voucher_no, voucher_type))
 
 	if not last_valuation_rate:
 		# Get valuation rate from last sle for the item against any warehouse

erpnext/stock/utils.py

@@ -231,7 +231,7 @@ def get_incoming_rate(args, raise_error_if_no_rate=True):
 		in_rate = get_valuation_rate(args.get('item_code'), args.get('warehouse'),
 			args.get('voucher_type'), voucher_no, args.get('allow_zero_valuation'),
 			currency=erpnext.get_company_currency(args.get('company')), company=args.get('company'),
-			raise_error_if_no_rate=raise_error_if_no_rate)
+			raise_error_if_no_rate=raise_error_if_no_rate, batch_no=args.get("batch_no"))
 
 	return flt(in_rate)