Util.Dif issue?

Automan72

I wrote the following program and it seems to me that the method Util.Dif() doesn't work properly with the array.
Is this the case?

void Main()
{
var rna1 = GenerateRandomBytes(32);
var rna2 = RandomNumberGenerator.GetBytes(32);

new { Row = string.Join(", ", rna1) }.Dump();
new { Row = string.Join(", ", rna2) }.Dump();

Util.HorizontalRun(true, rna1, rna2).Dump();
Util.Dif(rna1, rna2).Dump();

}

public static byte[] GenerateRandomBytes(int length)
{
using var rng = RandomNumberGenerator.Create();
var randomBytes = new byte[length];
rng.GetBytes(randomBytes);
return randomBytes;
}

i2van

If rows are completely different works as expected:

void Main()
{
    // TODO: Set both to the 1 to get strange result.
    const int firstRowIndex  = 1;
    const int secondRowIndex = 2;

    var rna1 = GenerateRandomBytes(32, firstRowIndex);
    var rna2 = GenerateRandomBytes(32, secondRowIndex);

    Util.Pivot(rna1).Dump();
    Util.Pivot(rna2).Dump();

    Util.Dif(rna1, rna2).Dump();
}

public static int[] GenerateRandomBytes(int length, int row)
{
    using var rng = System.Security.Cryptography.RandomNumberGenerator.Create();
    var randomBytes = new byte[length];
    rng.GetBytes(randomBytes);

    return randomBytes.Select(i => row*1000+i).ToArray();
}

i2van

1039 exists in both. Why it compares like that?

JoeAlbahari

Good point - it shouldn't attempt an element-by-element comparison if the lists are too dissimilar. This has now been fixed in 8.8.1.