public void pop() {
    Preconditions.checkState(!stack.isEmpty(), "Error in file properties stack pop, popping at 0");
    stack.remove(stack.size() - 1);
    updateProperties();
  }
@Test
  public void testPop_nothingToPop() {
    FilePropertiesStack testStack = new FilePropertiesStack();

    try {
      testStack.pop();
      Assert.fail();
    } catch (IllegalStateException ise) {
      Assert.assertEquals("Error in file properties stack pop, popping at 0", ise.getMessage());
    }
  }