using BenchmarkDotNet.Attributes;
using BenchmarkDotNet.Running;

BenchmarkSwitcher.FromAssembly(typeof(Tests).Assembly).Run(args);

[MemoryDiagnoser(false)]
public class Tests
{
    private IEnumerable<int> _whereSelect;
    private IEnumerable<int> _arrayReverse;
    private IEnumerable<int> _concatComplicated;

    [GlobalSetup]
    public void Setup()
    {
        _whereSelect = Enumerable.Range(0, 1000).Where(i => i % 2 == 0).Select(i => i * 2);
        _arrayReverse = Enumerable.Range(0, 1000).ToArray().Reverse();
        _concatComplicated = _whereSelect.Concat(_arrayReverse).Concat(_whereSelect).Concat(_arrayReverse);
    }

    [Benchmark] public int WhereSelect_First() => _whereSelect.First();
    [Benchmark] public int WhereSelect_Last() => _whereSelect.Last();

    [Benchmark] public int ArrayReverse_First() => _arrayReverse.First();
    [Benchmark] public int ArrayReverse_Last() => _arrayReverse.Last();

    [Benchmark] public int ConcatComplicated_First() => _concatComplicated.First();
    [Benchmark] public int ConcatComplicated_Last() => _concatComplicated.Last();
}