public void InsertTest()
{
var array = new NodeArray <IExpression>();
array.Add(new LiteralExpression("original-1"));
array.Add(new LiteralExpression("original-2"));
array.Insert(1, new LiteralExpression("insert-1"));
array.Insert(0, new LiteralExpression("insert-0"));
Assert.Equal(4, array.Length);
Assert.Equal("insert-0", array[0].Cast <LiteralExpression>().Text);
Assert.Equal("original-1", array[1].Cast <LiteralExpression>().Text);
Assert.Equal("insert-1", array[2].Cast <LiteralExpression>().Text);
Assert.Equal("original-2", array[3].Cast <LiteralExpression>().Text);
}