Fix reorder does not introduce new holes

taiga/projects/services/bulk_update_order.py

@@ -42,6 +42,11 @@ def apply_order_updates(base_orders: dict, new_orders: dict, *, remove_equal_ori
     invalid_keys = new_orders.keys() - base_orders.keys()
     [new_orders.pop(id, None) for id in invalid_keys]
 
+    # Remove the elements from new_orders contained in base_orders
+    if remove_equal_original:
+        common_keys = base_orders.keys() & new_orders.keys()
+        [new_orders.pop(id, None) for id in common_keys if new_orders[id] == base_orders[id]]
+
     # We will apply the multiple order changes by the new position order
     sorted_new_orders = [(k, v) for k, v in new_orders.items()]
     sorted_new_orders = sorted(sorted_new_orders, key=lambda e: e[1])
@@ -69,11 +74,6 @@ def apply_order_updates(base_orders: dict, new_orders: dict, *, remove_equal_ori
     removing_keys = [id for id in base_orders if id not in updated_order_ids]
     [base_orders.pop(id, None) for id in removing_keys]
 
-    # Remove elements that are equal to the original
-    if remove_equal_original:
-        common_keys = original_orders.keys() & base_orders.keys()
-        [base_orders.pop(id, None) for id in common_keys if base_orders[id] == original_orders[id]]
-
 
 def update_projects_order_in_bulk(bulk_data: list, field: str, user):
     """

tests/unit/test_order_updates.py

@@ -197,3 +197,18 @@ def test_apply_order_not_include_noop():
     }
     apply_order_updates(orders, new_orders, remove_equal_original=True)
     assert orders == {}
+
+
+def test_apply_order_does_no_generate_holes():
+    orders = {
+        "a": 0,
+        "b": 2,
+        "c": 1,
+        "z": 99,
+    }
+    new_orders = {
+        "c": 1,
+        "z": 99,
+    }
+    apply_order_updates(orders, new_orders, remove_equal_original=True)
+    assert orders == {}