public void DrawStatusBar_HappyPath_FillsLineAtBottom()
{
CharInfo[] actualBuffer = new CharInfo[4];
// Arrange
var screenBufferMock = new Mock <IScreenBuffer>();
screenBufferMock.SetupGet(sb => sb.Width).Returns(2);
screenBufferMock.SetupGet(sb => sb.Height).Returns(2);
screenBufferMock.Setup(sb => sb.Render(It.IsAny <Action <CharInfo[]> >()))
.Callback <Action <CharInfo[]> >(a => a(actualBuffer));
// Act
var screenController = new ScreenController(screenBufferMock.Object);
screenController.DrawStatusBar();
// Assert
const int attribute = 1 << 4 | 15;
actualBuffer[2].AsciiChar.Should().Be('\0');
actualBuffer[2].Attributes.Should().Be(attribute);
actualBuffer[3].AsciiChar.Should().Be('\0');
actualBuffer[3].Attributes.Should().Be(attribute);
}