text: # -*- coding: utf-8 -*-
  
  from src.Stack import Stack
  
  
  def test_empty_stack():
      s = Stack()
      assert s.size() == 0
      assert len(s) == 0
  
  
  def test_nonempty_stack():
      s = Stack()
      s.push(1)
      s.push(2)
  
      assert len(s) == 2
      assert s.pop() == 2
  
      assert len(s) == 1
      assert s.pop() == 1
  
      assert len(s) == 0
      assert s.pop() == None
  