fix: Added PO test and conversion factor fix

- Don't change conversion factor if stock uom and uom is the same
- Added PO test
- Added Accounts User basic role in PO
- Minor fixes, wrong variables

erpnext/buying/doctype/purchase_order/purchase_order.json

@@ -1068,7 +1068,7 @@
  "idx": 105,
  "is_submittable": 1,
  "links": [],
- "modified": "2020-04-24 12:13:14.186280",
+ "modified": "2020-06-12 14:08:11.777120",
  "modified_by": "Administrator",
  "module": "Buying",
  "name": "Purchase Order",
@@ -1112,6 +1112,12 @@
    "read": 1,
    "role": "Purchase Manager",
    "write": 1
+  },
+  {
+   "email": 1,
+   "print": 1,
+   "read": 1,
+   "role": "Accounts User"
   }
  ],
  "search_fields": "status, transaction_date, supplier,grand_total",

erpnext/buying/doctype/purchase_order/test_purchase_order.py

@@ -118,7 +118,7 @@ class TestPurchaseOrder(unittest.TestCase):
 		self.assertEqual(po.get("items")[0].amount, 1400)
 		self.assertEqual(get_ordered_qty(), existing_ordered_qty + 3)
 
-	
+
 	def test_add_new_item_in_update_child_qty_rate(self):
 		po = create_purchase_order(do_not_save=1)
 		po.items[0].qty = 4
@@ -144,7 +144,7 @@ class TestPurchaseOrder(unittest.TestCase):
 		self.assertEquals(len(po.get('items')), 2)
 		self.assertEqual(po.status, 'To Receive and Bill')
 
-	
+
 	def test_remove_item_in_update_child_qty_rate(self):
 		po = create_purchase_order(do_not_save=1)
 		po.items[0].qty = 4
@@ -185,6 +185,22 @@ class TestPurchaseOrder(unittest.TestCase):
 		self.assertEquals(len(po.get('items')), 1)
 		self.assertEqual(po.status, 'To Receive and Bill')
 
+	def test_update_child_qty_rate_perm(self):
+		po = create_purchase_order(item_code= "_Test Item", qty=4)
+
+		user = 'test@example.com'
+		test_user = frappe.get_doc('User', user)
+		test_user.add_roles("Accounts User")
+		frappe.set_user(user)
+
+		# update qty
+		trans_item = json.dumps([{'item_code' : '_Test Item', 'rate' : 200, 'qty' : 7, 'docname': po.items[0].name}])
+		self.assertRaises(frappe.ValidationError, update_child_qty_rate,'Purchase Order', trans_item, po.name)
+
+		# add new item
+		trans_item = json.dumps([{'item_code' : '_Test Item', 'rate' : 100, 'qty' : 2}])
+		self.assertRaises(frappe.ValidationError, update_child_qty_rate,'Purchase Order', trans_item, po.name)
+
 	def test_update_qty(self):
 		po = create_purchase_order()
 
@@ -689,7 +705,7 @@ class TestPurchaseOrder(unittest.TestCase):
 		po.save()
 		self.assertEqual(po.schedule_date, add_days(nowdate(), 2))
 
-	
+
 	def test_po_optional_blanket_order(self):
 		"""
 			Expected result: Blanket order Ordered Quantity should only be affected on Purchase Order with against_blanket_order = 1.

erpnext/controllers/accounts_controller.py

@@ -1137,7 +1137,7 @@ def set_sales_order_defaults(parent_doctype, parent_doctype_name, child_docname,
 	child_item.item_name = item.item_name
 	child_item.description = item.description
 	child_item.delivery_date = trans_item.get('delivery_date') or p_doc.delivery_date
-	child_item.conversion_factor = flt(d.get('conversion_factor')) or get_conversion_factor(item.item_code, item.stock_uom).get("conversion_factor") or 1.0
+	child_item.conversion_factor = flt(trans_item.get('conversion_factor')) or get_conversion_factor(item.item_code, item.stock_uom).get("conversion_factor") or 1.0
 	child_item.uom = item.stock_uom
 	child_item.warehouse = get_item_warehouse(item, p_doc, overwrite_warehouse=True)
 	if not child_item.warehouse:
@@ -1157,7 +1157,7 @@ def set_purchase_order_defaults(parent_doctype, parent_doctype_name, child_docna
 	child_item.item_name = item.item_name
 	child_item.description = item.description
 	child_item.schedule_date = trans_item.get('schedule_date') or p_doc.schedule_date
-	child_item.conversion_factor = flt(d.get('conversion_factor')) or get_conversion_factor(item.item_code, item.stock_uom).get("conversion_factor") or 1.0
+	child_item.conversion_factor = flt(trans_item.get('conversion_factor')) or get_conversion_factor(item.item_code, item.stock_uom).get("conversion_factor") or 1.0
 	child_item.uom = item.stock_uom
 	child_item.base_rate = 1 # Initiallize value will update in parent validation
 	child_item.base_amount = 1 # Initiallize value will update in parent validation
@@ -1237,7 +1237,7 @@ def update_child_qty_rate(parent_doctype, trans_items, parent_doctype_name, chil
 				prev_date, new_date = child_item.get("schedule_date") == d.get("schedule_date")
 
 			rate_unchanged = prev_rate == new_rate
-			qty_unchanged = prev_qty == prev_qty
+			qty_unchanged = prev_qty == new_qty
 			conversion_factor_unchanged = prev_con_fac == new_con_fac
 			date_unchanged = prev_date == new_date if prev_date and new_date else False # in case of delivery note etc
 			if rate_unchanged and qty_unchanged and conversion_factor_unchanged and date_unchanged:
@@ -1253,13 +1253,16 @@ def update_child_qty_rate(parent_doctype, trans_items, parent_doctype_name, chil
 						 .format(child_item.idx, child_item.item_code))
 		else:
 			child_item.rate = flt(d.get("rate"))
-		
+
 		if d.get("conversion_factor"):
-			child_item.conversion_factor = flt(d.get('conversion_factor'))
+			if child_item.stock_uom == child_item.uom:
+				child_item.conversion_factor = 1
+			else:
+				child_item.conversion_factor = flt(d.get('conversion_factor'))
 
 		if d.get("delivery_date") and parent_doctype == 'Sales Order':
 			child_item.delivery_date = d.get('delivery_date')
-		
+
 		if d.get("schedule_date") and parent_doctype == 'Purchase Order':
 			child_item.schedule_date = d.get('schedule_date')