c# - 单元测试未涵盖 LINQ `Any`

Question

我有这个方法:

/// <summary>
/// Moves piece to location, does not verify that this is a valid move
/// </summary>
/// <param name="dest"></param>
public virtual void Move(Coordinate dest)
{
    if (Board.IsPieceAtLocation(dest))
    {
        if (GetAllPossibleKills().Any(p => p.BoardLocation == dest))
        {
            Board.KillPieceAtLocation(dest);
        }
        else
        {
            throw new LocationOccupiedException("Board location already occupied and kill is not valid",this, Board.GetPieceAtLocation(dest));
        }
    }
    BoardLocation = dest;
}

它包含在两个单元测试中:

[Test]
public void LocationOccupiedTest()
{
    Board board = new Board();
    board.GenerateNewGamePieces();
    Assert.Throws<LocationOccupiedException>(()=>board.GetKing(false).Move(new Coordinate(0,0)));
}

[Test]
public void KillPieceTest()
{
    Board board = new Board();
    board.GenerateNewGamePieces();
    Piece knight = board.GetPieceAtLocation(new Coordinate(1, 0));
    knight.Move(new Coordinate(1,4));
    Assert.DoesNotThrow(()=>knight.Move(new Coordinate(0,6)));
}

根据覆盖率分析，除了: if (GetAllPossibleKills().Any(p => p.BoardLocation == dest))您可以在每行代码旁边看到覆盖状态:

我不明白在遍历 if 语句的两个分支的情况下怎么会这样。
我怎样才能得到这个？

Answer 1

我怀疑问题在于您没有测试 Any 的所有可能的执行路径。 .
您可能需要添加额外的测试用例，以确保在存在其他有效目标时(例如，感谢示例 @Persistence)覆盖(例如)非法移动。

要修复此特定示例，您需要添加一个测试用例，以便在有其他有效杀死目标时移动到不是有效杀死目标的占用空间。

[Test]
public void MoveToOccupiedWithOtherValidTargets()
{
    Board board = new Board();
    board.GenerateNewGamePieces();
    Piece king = board.GetKing(true);
    king.Move(new Coordinate(0,5));
    board.GetPieceAtLocation(new Coordinate(0,1)).Move(new Coordinate(0,4));
    Assert.Throws<LocationOccupiedException>(()=>king.Move(new Coordinate(0,4)));
}