fix(stock): treat a 0% BOM cost allocation as no cost (#57736)

* fix(stock): treat a 0% BOM cost allocation as no cost

A BOM splits its raw material cost between the finished good and its
secondary items, and validate_total_cost_allocation holds the two to
100%. An allocation of 0% therefore means the finished good takes
everything and the secondary item carries no cost.

The code read it as no allocation at all. A cost_allocation_per of 0 is
falsy, so the branch was skipped, the row kept a rate of zero, and the
fallback below handed it the item's own valuation rate. Producing 1000 of
raw material into a finished good at 100% and scrap at 0% booked 1000 to
the finished good and another 100 to the scrap.

Apply the BOM's share whatever it is, and mark the rate as derived so the
valuation fallback leaves a deliberate zero alone. rate_derived_from_consumption
becomes has_derived_rate, since it now guards more than the consumption case.

* test(stock): cover a secondary item allocated 0% of the cost

The finished good takes the full 1000 and the scrap row is worth nothing.

(cherry picked from commit 7d901ed92c)

# Conflicts:
#	erpnext/stock/doctype/stock_entry/stock_entry.py
#	erpnext/stock/doctype/stock_entry/test_stock_entry.py

erpnext/stock/doctype/stock_entry/stock_entry.py

@@ -1548,6 +1548,76 @@ class StockEntry(StockController, SubcontractingInwardController):
 			)
 		return self._consumption_entries
 
+<<<<<<< HEAD
+=======
+	def _set_incoming_item_rate(
+		self,
+		d,
+		outgoing_items_cost,
+		raise_error_if_no_rate,
+		zero_valuation_items,
+		bom_cost_allocation_per=None,
+		has_consumption_basis=False,
+	):
+		has_derived_rate = False
+
+		if d.allow_zero_valuation_rate and d.basic_rate and self.purpose != "Receive from Customer":
+			d.basic_rate = 0.0
+			zero_valuation_items.append(d.item_code)
+		elif d.is_finished_item:
+			if self.purpose == "Manufacture":
+				d.basic_rate = self.get_basic_rate_for_manufactured_item(
+					d.transfer_qty, outgoing_items_cost, has_consumption_basis
+				)
+				has_derived_rate = has_consumption_basis
+			elif self.purpose == "Repack":
+				d.basic_rate = self.get_basic_rate_for_repacked_items(d.transfer_qty, outgoing_items_cost)
+				# Repack rate comes from consumed source-warehouse rows, not consumption entries
+				has_derived_rate = any(item.s_warehouse for item in self.get("items"))
+
+			if self.bom_no:
+				d.basic_rate *= bom_cost_allocation_per / 100
+		elif d.secondary_item_type and d.bom_secondary_item:
+			cost_allocation_per = flt(
+				frappe.get_value("BOM Secondary Item", d.bom_secondary_item, "cost_allocation_per")
+			)
+			if flt(d.transfer_qty):
+				d.basic_rate = (outgoing_items_cost * (cost_allocation_per / 100)) / d.transfer_qty
+				has_derived_rate = True
+
+		# A rate of zero that was derived rather than left unset is a real cost. Falling back to
+		# the item's valuation here would value free inputs, or an unallocated row, as output.
+		if not d.basic_rate and not d.allow_zero_valuation_rate and not has_derived_rate:
+			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,
+				batch_no=d.batch_no,
+				serial_and_batch_bundle=d.serial_and_batch_bundle,
+			)
+
+		# do not round off basic rate to avoid precision loss
+		d.basic_rate = flt(d.basic_rate)
+		d.basic_amount = flt(flt(d.transfer_qty) * flt(d.basic_rate), d.precision("basic_amount"))
+
+	def _notify_zero_valuation_rate(self, items):
+		if len(items) > 1:
+			message = _(
+				"Items rate has been updated to zero as Allow Zero Valuation Rate is checked for the following items: {0}"
+			).format(", ".join(frappe.bold(item) for item in items))
+		else:
+			message = _(
+				"Item rate has been updated to zero as Allow Zero Valuation Rate is checked for item {0}"
+			).format(frappe.bold(items[0]))
+
+		frappe.msgprint(message, alert=True)
+
+>>>>>>> 7d901ed92c (fix(stock): treat a 0% BOM cost allocation as no cost (#57736))
 	def set_rate_for_outgoing_items(self, reset_outgoing_rate=True, raise_error_if_no_rate=True):
 		outgoing_items_cost = 0.0
 		for d in self.get("items"):

erpnext/stock/doctype/stock_entry/test_stock_entry.py

@@ -2737,6 +2737,197 @@ class TestStockEntry(ERPNextTestSuite):
 		self.assertEqual(fg_sle.incoming_rate, 0)
 		self.assertEqual(fg_sle.stock_value_difference, 0)
 
+<<<<<<< HEAD
+=======
+	def test_secondary_item_type_does_not_waive_inspection_outside_manufacturing(self):
+		"""A stray secondary item type must not let a QI-required item through a receipt."""
+		item = make_item(
+			properties={
+				"is_stock_item": 1,
+				"valuation_rate": 50,
+				"inspection_required_before_purchase": 1,
+			}
+		).name
+
+		def receipt(secondary_item_type):
+			se = frappe.new_doc("Stock Entry")
+			se.purpose = se.stock_entry_type = "Material Receipt"
+			se.company = "_Test Company"
+			se.inspection_required = 1
+			se.append(
+				"items",
+				{
+					"item_code": item,
+					"t_warehouse": "_Test Warehouse - _TC",
+					"qty": 10,
+					"conversion_factor": 1,
+					"secondary_item_type": secondary_item_type,
+				},
+			)
+			return se
+
+		self.assertRaises(QualityInspectionRequiredError, receipt("").submit)
+		self.assertRaises(QualityInspectionRequiredError, receipt("Scrap").submit)
+
+	def test_manufacture_balances_secondary_item_added_without_a_bom(self):
+		"""A secondary item with no BOM link is costed out of the finished good, as legacy scrap was."""
+		rm_item = make_item(properties={"is_stock_item": 1}).name
+		fg_item = make_item(properties={"is_stock_item": 1}).name
+		scrap_item = make_item(properties={"is_stock_item": 1, "valuation_rate": 20}).name
+		warehouse = "_Test Warehouse - _TC"
+
+		make_stock_entry(item_code=rm_item, target=warehouse, qty=10, basic_rate=100)
+
+		se = frappe.new_doc("Stock Entry")
+		se.purpose = se.stock_entry_type = "Manufacture"
+		se.company = "_Test Company"
+		se.append(
+			"items", {"item_code": rm_item, "s_warehouse": warehouse, "qty": 10, "conversion_factor": 1}
+		)
+		se.append(
+			"items",
+			{
+				"item_code": fg_item,
+				"t_warehouse": warehouse,
+				"qty": 10,
+				"is_finished_item": 1,
+				"conversion_factor": 1,
+			},
+		)
+		se.append(
+			"items",
+			{
+				"item_code": scrap_item,
+				"t_warehouse": warehouse,
+				"qty": 5,
+				"secondary_item_type": "Scrap",
+				"conversion_factor": 1,
+			},
+		)
+		se.save()
+
+		scrap_row = se.items[2]
+		self.assertEqual(flt(scrap_row.basic_rate), 20.0)
+		self.assertEqual(flt(scrap_row.basic_amount), 100.0)
+
+		fg_row = se.items[1]
+		self.assertEqual(flt(fg_row.basic_rate), 90.0)
+		self.assertEqual(flt(fg_row.basic_amount), 900.0)
+
+		self.assertEqual(flt(se.total_incoming_value), 1000.0)
+		self.assertEqual(flt(se.total_outgoing_value), 1000.0)
+		self.assertEqual(flt(se.value_difference), 0.0)
+
+	def test_repack_allocates_cost_to_secondary_item(self):
+		"""A Repack secondary item takes its own BOM share, not the finished good's."""
+		rm_item = make_item(properties={"is_stock_item": 1, "valuation_rate": 100}).name
+		fg_item = make_item(properties={"is_stock_item": 1}).name
+		scrap_item = make_item(properties={"is_stock_item": 1, "valuation_rate": 20}).name
+		warehouse = "_Test Warehouse - _TC"
+
+		bom = frappe.get_doc(
+			{
+				"doctype": "BOM",
+				"item": fg_item,
+				"currency": "INR",
+				"quantity": 10,
+				"company": "_Test Company",
+			}
+		)
+		bom.append("items", {"item_code": rm_item, "qty": 10})
+		bom.append(
+			"secondary_items",
+			{
+				"secondary_item_type": "Scrap",
+				"item_code": scrap_item,
+				"item_name": scrap_item,
+				"qty": 5,
+				"cost_allocation_per": 25,
+				"process_loss_per": 0,
+			},
+		)
+		bom.insert()
+		bom.submit()
+		self.assertEqual(flt(bom.cost_allocation_per), 75.0)
+
+		make_stock_entry(item_code=rm_item, target=warehouse, qty=100, basic_rate=100)
+
+		se = frappe.new_doc("Stock Entry")
+		se.purpose = se.stock_entry_type = "Repack"
+		se.company = "_Test Company"
+		se.from_bom = 1
+		se.bom_no = bom.name
+		se.fg_completed_qty = 10
+		se.from_warehouse = warehouse
+		se.to_warehouse = warehouse
+		se.get_items()
+		se.save()
+
+		fg_row = next(d for d in se.items if d.is_finished_item)
+		scrap_row = next(d for d in se.items if d.secondary_item_type)
+
+		self.assertFalse(scrap_row.is_finished_item)
+		self.assertEqual(flt(scrap_row.basic_amount), 250.0)
+		self.assertEqual(flt(fg_row.basic_amount), 750.0)
+
+		self.assertEqual(flt(se.total_incoming_value), 1000.0)
+		self.assertEqual(flt(se.total_outgoing_value), 1000.0)
+		self.assertEqual(flt(se.value_difference), 0.0)
+
+	def test_secondary_item_with_zero_cost_allocation_carries_no_value(self):
+		"""A BOM that allocates 0% to a secondary item gives the finished good everything."""
+		from erpnext.manufacturing.doctype.work_order.test_work_order import make_wo_order_test_record
+		from erpnext.manufacturing.doctype.work_order.work_order import (
+			make_stock_entry as make_stock_entry_from_wo,
+		)
+
+		rm_item = make_item(properties={"is_stock_item": 1, "valuation_rate": 100}).name
+		fg_item = make_item(properties={"is_stock_item": 1}).name
+		scrap_item = make_item(properties={"is_stock_item": 1, "valuation_rate": 20}).name
+		warehouse = "_Test Warehouse - _TC"
+
+		bom = frappe.get_doc(
+			{
+				"doctype": "BOM",
+				"item": fg_item,
+				"currency": "INR",
+				"quantity": 10,
+				"company": "_Test Company",
+			}
+		)
+		bom.append("items", {"item_code": rm_item, "qty": 10})
+		bom.append(
+			"secondary_items",
+			{
+				"secondary_item_type": "Scrap",
+				"item_code": scrap_item,
+				"item_name": scrap_item,
+				"qty": 5,
+				"cost_allocation_per": 0,
+				"process_loss_per": 0,
+			},
+		)
+		bom.insert()
+		bom.submit()
+		self.assertEqual(flt(bom.cost_allocation_per), 100.0)
+
+		make_stock_entry(item_code=rm_item, target=warehouse, qty=100, basic_rate=100)
+		wo = make_wo_order_test_record(
+			production_item=fg_item, bom_no=bom.name, qty=10, skip_transfer=1, source_warehouse=warehouse
+		)
+
+		se = frappe.get_doc(make_stock_entry_from_wo(wo.name, "Manufacture", 10))
+		se.save()
+
+		scrap_row = next(d for d in se.items if d.secondary_item_type)
+		fg_row = next(d for d in se.items if d.is_finished_item)
+
+		self.assertEqual(flt(scrap_row.basic_rate), 0.0)
+		self.assertEqual(flt(scrap_row.basic_amount), 0.0)
+		self.assertEqual(flt(fg_row.basic_amount), 1000.0)
+		self.assertEqual(flt(se.value_difference), 0.0)
+
+>>>>>>> 7d901ed92c (fix(stock): treat a 0% BOM cost allocation as no cost (#57736))
 	def _make_wo_for_free_raw_material(self, rm_item, fg_item, bom_no):
 		from erpnext.manufacturing.doctype.work_order.test_work_order import make_wo_order_test_record
 		from erpnext.manufacturing.doctype.work_order.work_order import (