.update(...) with no update argument sets last_pk

Author: simonw

sqlite_utils/db.py

@@ -783,6 +783,8 @@ def update(self, pk_values, updates=None, alter=False):
             pk_values = [pk_values]
         # Sanity check that the record exists (raises error if not):
         self.get(pk_values)
+        if not updates:
+            return self
         args = []
         sets = []
         wheres = []

tests/test_update.py

@@ -64,3 +64,20 @@ def test_update_alter(fresh_db):
             "int_col": -10,
         }
     ] == list(table.rows)
+
+
+def test_update_with_no_values_sets_last_pk(fresh_db):
+    table = fresh_db.table("dogs", pk="id")
+    table.insert_all([{
+        "id": 1,
+        "name": "Cleo",
+    }, {
+        "id": 2,
+        "name": "Pancakes"
+    }])
+    table.update(1)
+    assert 1 == table.last_pk
+    table.update(2)
+    assert 2 == table.last_pk
+    with pytest.raises(NotFoundError):
+        table.update(3)