fix: compare updated item quantities in stock UOM (#58603)

erpnext/accounts/services/child_item_update.py

@@ -32,8 +32,7 @@ class ChildItemUpdater:
 		self.child_docname = child_docname
 		self.parent = frappe.get_doc(parent_doctype, parent_doctype_name)
 		self.allow_zero_qty = get_allow_zero_qty(parent_doctype)
-		self._ordered_items: dict | None = None
-		self._purchased_items: dict | None = None
+		self._transacted_stock_qty: dict | None = None
 
 	def update(self, trans_items: str | list) -> None:
 		"""Process item additions, edits, and deletions from trans_items JSON."""
@@ -48,11 +47,15 @@ class ChildItemUpdater:
 		self._check_permissions("write")
 
 		if self.parent_doctype == "Quotation":
-			self._ordered_items = get_ordered_items(self.parent.name)
-			items_added_or_removed |= validate_and_delete_children(self.parent, data, self._ordered_items)
+			self._transacted_stock_qty = get_ordered_items(self.parent.name)
+			items_added_or_removed |= validate_and_delete_children(
+				self.parent, data, self._transacted_stock_qty
+			)
 		elif self.parent_doctype == "Supplier Quotation":
-			self._purchased_items = get_purchased_items(self.parent.name)
-			items_added_or_removed |= validate_and_delete_children(self.parent, data, self._purchased_items)
+			self._transacted_stock_qty = get_purchased_items(self.parent.name)
+			items_added_or_removed |= validate_and_delete_children(
+				self.parent, data, self._transacted_stock_qty
+			)
 		else:
 			items_added_or_removed |= validate_and_delete_children(self.parent, data)
 
@@ -71,6 +74,7 @@ class ChildItemUpdater:
 			else:
 				self._check_permissions("write")
 				child_item = frappe.get_doc(self.parent_doctype + " Item", d.get("docname"))
+				d["conversion_factor"] = self._get_new_conversion_factor(child_item, d)
 
 				change_state = get_child_item_change_state(self.parent_doctype, child_item, d)
 				rate_unchanged = change_state.rate_unchanged
@@ -251,6 +255,22 @@ class ChildItemUpdater:
 			item_row,
 		)
 
+	def _get_new_conversion_factor(self, child_item, new_data: dict) -> float:
+		current_factor = flt(child_item.get("conversion_factor")) or 1
+		uom = new_data.get("uom") or child_item.get("uom")
+
+		if uom == child_item.get("stock_uom"):
+			return 1
+
+		requested_factor = flt(new_data.get("conversion_factor"))
+		if requested_factor:
+			return requested_factor
+
+		if uom == child_item.get("uom"):
+			return current_factor
+
+		return flt(get_conversion_factor(child_item.item_code, uom).get("conversion_factor")) or 1
+
 	def _validate_quantity_and_rate(self, child_item, new_data: dict, rate_unchanged: bool | None) -> None:
 		if not flt(new_data.get("qty")) and not self.allow_zero_qty:
 			frappe.throw(
@@ -264,24 +284,24 @@ class ChildItemUpdater:
 			"Sales Order": ("delivered_qty", _("Cannot set quantity less than delivered quantity.")),
 			"Purchase Order": ("received_qty", _("Cannot set quantity less than received quantity.")),
 		}
+		old_conversion_factor = flt(child_item.get("conversion_factor")) or 1
+		new_conversion_factor = flt(new_data.get("conversion_factor")) or old_conversion_factor
+		new_stock_qty = flt(new_data.get("qty")) * new_conversion_factor
 
 		if self.parent_doctype in qty_limits:
 			qty_field, error_message = qty_limits[self.parent_doctype]
-			if flt(new_data.get("qty")) < flt(child_item.get(qty_field)):
+			old_stock_qty = flt(child_item.get(qty_field)) * old_conversion_factor
+			if new_stock_qty < old_stock_qty:
 				frappe.throw(
 					_("Row #{0}:").format(new_data.get("idx")) + error_message,
 					title=_("Invalid Qty"),
 				)
 
-		if self.parent_doctype not in ("Quotation", "Supplier Quotation"):
+		if not self._transacted_stock_qty:
 			return
 
-		items_map = self._ordered_items if self.parent_doctype == "Quotation" else self._purchased_items
-		if not items_map:
-			return
-
-		qty_to_check = items_map.get(child_item.name)
-		if not qty_to_check:
+		old_stock_qty = self._transacted_stock_qty.get(child_item.name)
+		if not old_stock_qty:
 			return
 
 		if not rate_unchanged:
@@ -291,7 +311,7 @@ class ChildItemUpdater:
 				).format(frappe.bold(new_data.get("item_code")))
 			)
 
-		if flt(new_data.get("qty")) < qty_to_check:
+		if new_stock_qty < old_stock_qty:
 			frappe.throw(_("Cannot reduce quantity than ordered or purchased quantity"))
 
 	def _validate_fg_item_for_subcontracting(self, new_data: dict, is_new: bool) -> None:
@@ -581,22 +601,18 @@ def update_child_item_rate_and_discount(
 
 
 def update_child_item_uom_and_weight(child_item, new_data) -> None:
-	conv_fac_precision = child_item.precision("conversion_factor") or 2
-
 	if new_data.get("conversion_factor"):
 		if child_item.stock_uom == child_item.uom:
 			child_item.conversion_factor = 1
 		else:
-			child_item.conversion_factor = flt(new_data.get("conversion_factor"), conv_fac_precision)
+			child_item.conversion_factor = flt(new_data.get("conversion_factor"))
 
 	if new_data.get("uom"):
 		child_item.uom = new_data.get("uom")
 		conversion_factor = flt(
 			get_conversion_factor(child_item.item_code, child_item.uom).get("conversion_factor")
 		)
-		child_item.conversion_factor = (
-			flt(new_data.get("conversion_factor"), conv_fac_precision) or conversion_factor
-		)
+		child_item.conversion_factor = flt(new_data.get("conversion_factor")) or conversion_factor
 
 	if child_item.get("weight_per_unit"):
 		child_item.total_weight = flt(

erpnext/buying/doctype/purchase_order/test_purchase_order.py

@@ -333,6 +333,38 @@ class TestPurchaseOrder(ERPNextTestSuite):
 		self.assertEqual(po.get("items")[0].amount, 1400)
 		self.assertEqual(get_ordered_qty(), existing_ordered_qty + 3)
 
+	def test_update_child_qty_with_conversion_factor_after_receipt(self):
+		item = make_item(uoms=[{"uom": "Box", "conversion_factor": 5}])
+		purchase_order = create_purchase_order(item_code=item.item_code, qty=6, do_not_save=True)
+		purchase_order.items[0].uom = "Box"
+		purchase_order.items[0].conversion_factor = 5
+		purchase_order.save()
+		purchase_order.submit()
+		create_pr_against_po(purchase_order.name, 2)
+
+		row = purchase_order.items[0]
+		trans_items = json.dumps(
+			[
+				{
+					"item_code": row.item_code,
+					"rate": row.rate,
+					"qty": 4,
+					"uom": row.uom,
+					"conversion_factor": 2,
+					"docname": row.name,
+				}
+			]
+		)
+
+		self.assertRaisesRegex(
+			frappe.ValidationError,
+			"Cannot set quantity less than received quantity",
+			update_child_qty_rate,
+			"Purchase Order",
+			trans_items,
+			purchase_order.name,
+		)
+
 	def test_update_child_adding_new_item(self):
 		po = create_purchase_order(do_not_save=1)
 		po.items[0].qty = 4

erpnext/buying/doctype/supplier_quotation/supplier_quotation.py

@@ -262,7 +262,7 @@ def get_purchased_items(supplier_quotation: str):
 		frappe.get_all(
 			"Purchase Order Item",
 			filters={"supplier_quotation": supplier_quotation, "docstatus": 1},
-			fields=["supplier_quotation_item", {"SUM": "qty"}],
+			fields=["supplier_quotation_item", {"SUM": "stock_qty"}],
 			group_by="supplier_quotation_item",
 			as_list=1,
 		)

erpnext/buying/doctype/supplier_quotation/test_supplier_quotation.py

@@ -127,6 +127,52 @@ class TestPurchaseOrder(ERPNextTestSuite):
 			frappe.ValidationError, update_child_qty_rate, "Supplier Quotation", trans_item, sq.name
 		)
 
+	def test_update_child_qty_with_conversion_factor_after_purchase(self):
+		from erpnext.stock.doctype.item.test_item import make_item
+
+		item = make_item(uoms=[{"uom": "Box", "conversion_factor": 5}])
+		supplier_quotation = frappe.copy_doc(self.globalTestRecords["Supplier Quotation"][0])
+		supplier_quotation.items[0].item_code = item.item_code
+		supplier_quotation.items[0].qty = 6
+		supplier_quotation.items[0].uom = "Box"
+		supplier_quotation.items[0].conversion_factor = 5
+		supplier_quotation.insert()
+		supplier_quotation.submit()
+
+		purchase_order = make_purchase_order(supplier_quotation.name)
+		purchase_order.schedule_date = add_days(today(), 1)
+		purchase_order.items[0].qty = 2
+		purchase_order.save()
+		purchase_order.submit()
+
+		def update_qty(qty):
+			row = supplier_quotation.items[0]
+			trans_items = json.dumps(
+				[
+					{
+						"item_code": row.item_code,
+						"rate": row.rate,
+						"qty": qty,
+						"uom": row.uom,
+						"conversion_factor": 2,
+						"docname": row.name,
+					}
+				]
+			)
+			update_child_qty_rate("Supplier Quotation", trans_items, supplier_quotation.name)
+
+		update_qty(5)
+		supplier_quotation.reload()
+		self.assertEqual(supplier_quotation.items[0].conversion_factor, 2)
+		self.assertEqual(supplier_quotation.items[0].stock_qty, 10)
+
+		self.assertRaisesRegex(
+			frappe.ValidationError,
+			"Cannot reduce quantity than ordered or purchased quantity",
+			update_qty,
+			4,
+		)
+
 	def test_update_supplier_quotation_child_remove_item(self):
 		sq = frappe.copy_doc(self.globalTestRecords["Supplier Quotation"][0])
 		sq.submit()

erpnext/selling/doctype/quotation/test_quotation.py

@@ -156,6 +156,46 @@ class TestQuotation(ERPNextTestSuite):
 		qo.reload()
 		self.assertEqual(len(qo.get("items")), 1)
 
+	def test_update_child_qty_with_uom_conversion_factor(self):
+		from erpnext.stock.doctype.item.test_item import make_item
+
+		item = make_item(uoms=[{"uom": "Box", "conversion_factor": 5}])
+		quotation = make_quotation(item_code=item.item_code, qty=6, uom="Box", do_not_submit=1)
+		quotation.submit()
+
+		sales_order = make_sales_order(quotation.name)
+		sales_order.delivery_date = nowdate()
+		sales_order.items[0].qty = 2
+		sales_order.save()
+		sales_order.submit()
+
+		quotation.reload()
+		self.assertEqual(quotation.items[0].ordered_qty, 10)
+
+		def update_qty(qty, conversion_factor=None):
+			item = quotation.items[0]
+			trans_items = json.dumps(
+				[
+					{
+						"item_code": item.item_code,
+						"description": item.description,
+						"rate": item.rate,
+						"qty": qty,
+						"uom": item.uom,
+						"conversion_factor": conversion_factor or item.conversion_factor,
+						"docname": item.name,
+					}
+				]
+			)
+			update_child_qty_rate("Quotation", trans_items, quotation.name)
+
+		update_qty(5, conversion_factor=2)
+		quotation.reload()
+		self.assertEqual(quotation.items[0].conversion_factor, 2)
+		self.assertEqual(quotation.items[0].stock_qty, 10)
+
+		self.assertRaises(frappe.ValidationError, update_qty, 4)
+
 	def test_quotation_qty(self):
 		qo = make_quotation(qty=0, do_not_save=True)
 		with self.assertRaises(InvalidQtyError):

erpnext/selling/doctype/sales_order/test_sales_order.py

@@ -978,6 +978,46 @@ class TestSalesOrder(ERPNextTestSuite):
 		)
 		self.assertRaises(frappe.ValidationError, update_child_qty_rate, "Sales Order", trans_item, so.name)
 
+	def test_update_child_qty_with_conversion_factor_after_delivery(self):
+		item = make_item(uoms=[{"uom": "Box", "conversion_factor": 5}])
+		sales_order = make_sales_order(item_code=item.item_code, qty=6, uom="Box")
+		create_dn_against_so(sales_order.name, 2)
+
+		row = sales_order.items[0]
+		trans_items = json.dumps(
+			[
+				{
+					"item_code": row.item_code,
+					"rate": row.rate,
+					"qty": 4,
+					"uom": row.uom,
+					"conversion_factor": 2,
+					"docname": row.name,
+				}
+			]
+		)
+
+		self.assertRaisesRegex(
+			frappe.ValidationError,
+			"Cannot set quantity less than delivered quantity",
+			update_child_qty_rate,
+			"Sales Order",
+			trans_items,
+			sales_order.name,
+		)
+
+	def test_update_child_preserves_conversion_factor_precision(self):
+		from erpnext.accounts.services.child_item_update import update_child_item_uom_and_weight
+
+		item = make_item(properties={"stock_uom": "Kg"}, uoms=[{"uom": "Box", "conversion_factor": 2}])
+		sales_order = make_sales_order(item_code=item.item_code, qty=6, uom="Box")
+		conversion_factor = 1.123456789123
+		row = sales_order.items[0]
+
+		update_child_item_uom_and_weight(row, {"conversion_factor": conversion_factor})
+
+		self.assertEqual(row.conversion_factor, conversion_factor)
+
 	def test_update_child_with_precision(self):
 		from frappe.custom.doctype.property_setter.property_setter import make_property_setter
 		from frappe.model.meta import get_field_precision