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    [TestMethod]
    public void TestGraphDoesNotHaveSelfLinksOrDuplicateEdges()
    {
        var items = SmallVectors().Take(100)
            .Select((v, i) => (Id: (ulong)i, Vector: v))
            .ToArray();

        var graph = new SmallWorld<(ulong Id, float[] Vector), float>(
            distance: (a, b) => CosineDistance.NonOptimized(a.Vector, b.Vector),
            generator: new DeterministicGenerator(),
            parameters: new()
        );
        graph.AddItems(items);

        var underlyingGraph = (Graph<(ulong Id, float[] Vector), float>)graph.GetType()
            .GetField("Graph", BindingFlags.Instance | BindingFlags.NonPublic)
            .GetValue(graph);

        List<(int From, int To, int Layer, string Type)> badEdges = new();
        for (var i = 0; i < underlyingGraph.GraphCore.Nodes.Count; ++i)
        {
            var node = underlyingGraph.GraphCore.Nodes[i];
            for (var l = 0; l <= node.MaxLayer; ++l)
            {
                var connections = node[l];
                foreach (var group in connections.GroupBy(c => c))
                {
                    if (group.Key == i) { badEdges.Add((i, group.Key, l, "self-link")); }
                    if (group.Count() > 1) { badEdges.Add((i, group.Key, l, "duplicate")); }
                }
            }
        }

private IEnumerable<float[]> SmallVectors()
    {
        Random random = new(Seed: 1234);
        while (true)
        {
            var vector = new float[10];
            for (var j = 0; j < vector.Length; ++j)
            {
                vector[j] = random.NextSingle();
            }
            yield return vector;
        }
    }

    internal sealed class DeterministicGenerator : IProvideRandomValues
    {
        private readonly Random _random = new(Seed: 12345);

        public bool IsThreadSafe => false;

        public int Next(int minValue, int maxValue) => this._random.Next(minValue, maxValue);

        public float NextFloat() => this._random.NextSingle();

        public void NextFloats(Span<float> buffer)
        {
            for (var i = 0; i < buffer.Length; ++i)
            {
                buffer[i] = this.NextFloat();
            }
        }
    }