public void IsPushStackTrue()
        {
            var testStack = new LinkListStack <int>();

            var condition = testStack.Push(1);

            Assert.True(condition);
        }
        public void IsPeekEqualToLastValuePush(int data)
        {
            var testStack = new LinkListStack <int>();

            testStack.Push(data);
            testStack.Push(data);
            testStack.Push(data);
            testStack.Push(data);


            Assert.Equal(data, testStack.Peek());
        }