public void TestReactΔ()
{
var f = new MapFunction<int, int>(x => x + 1);
var numbers = new[] {10, 7, 12, 13, 6};
var value = f[numbers];
Assert.That(f.React(value, numbers.ToList().ToLog(Δ1.Empty)).Δ, Is.EqualTo(Δ1.Empty));
Assert.That(f.React(value, numbers.ToList().Mutate(Expressions.Numbers(4).ToIns(), (key, i) => 26)).Δ, Is.EqualTo(Expressions.Numbers(4).ToIns()));
Assert.That(f.React(value, numbers.ToList().Mutate(Expressions.Numbers(4).ToIns(), (key, i) => 13)).Δ, Is.EqualTo(Expressions.Numbers(4).ToIns()));
Assert.That(f.React(value, numbers.ToList().Mutate(Expressions.Numbers(5).ToIns(), (key, i) => 26)).Δ, Is.EqualTo(Expressions.Numbers(5).ToIns()));
Assert.That(f.React(value, numbers.ToList().Mutate(Expressions.Numbers(5).ToIns(), (key, i) => 7)).Δ, Is.EqualTo(Expressions.Numbers(5).ToIns()));
Assert.That(f.React(value, numbers.ToList().Mutate(Expressions.Numbers(1).ToDel(), (key, i) => 26)).Δ, Is.EqualTo(Expressions.Numbers(1).ToDel()));
Assert.That(f.React(value, numbers.ToList().Mutate(Expressions.Numbers(3).ToDel(), (key, i) => 26)).Δ, Is.EqualTo(Expressions.Numbers(3).ToDel()));
}
