Update updated_at when Todo state changes

app/models/todo.rb

@@ -110,7 +110,7 @@ class Todo < ApplicationRecord
       base = where.not(state: new_state).except(:order)
       ids = base.pluck(:id)
 
-      base.update_all(state: new_state)
+      base.update_all(state: new_state, updated_at: Time.now)
 
       ids
     end

spec/models/todo_spec.rb

@@ -389,5 +389,17 @@ describe Todo do
 
       expect(described_class.update_state(:pending)).to be_empty
     end
+
+    it 'updates updated_at' do
+      create(:todo, :pending)
+
+      Timecop.freeze(1.day.from_now) do
+        expected_update_date = Time.now.utc
+
+        ids = described_class.update_state(:done)
+
+        expect(Todo.where(id: ids).map(&:updated_at)).to all(be_like_time(expected_update_date))
+      end
+    end
   end
 end