public void SwapLinesWithPrev_SingleBlock()
{
Init();
lines.SetText("line0\nline1\nline2\nline3");
LineIterator iterator = lines.GetLineRange(0, lines.LinesCount);
iterator.MoveNext();
iterator.MoveNext();
Assert.AreEqual("line1\n", iterator.current.Text);
iterator.SwapCurrent(true);
AssertText("line1\nline0\nline2\nline3");
iterator.MoveNext();
Assert.AreEqual("line2\n", iterator.current.Text);
iterator.SwapCurrent(true);
AssertText("line1\nline2\nline0\nline3");
}