public void NotDeleteOutsideOfBoundaries(int count)
        {
            // Arrange
            var line = new InMemoryLineView();

            // Act, Assert
            Assert.Throws <ArgumentOutOfRangeException>(() => line.Delete(count));
        }
        public void Delete(string startValue, int startPos,
                           int deleteCount, string expextedValue, int expextedPos)
        {
            // Arrange
            var line = new InMemoryLineView();

            line.Type(startValue);
            line.MoveTo(startPos);

            // Act
            line.Delete(deleteCount);

            // Assert
            Assert.Equal(expextedValue, line.ToString());
            Assert.Equal(expextedPos, line.Position);
        }