public async Task Should_call_creator_once_when_context_exists()
{
using (sut.StartContext())
{
var value1 = sut.GetOrCreate("Key", () => ++ called);
await Task.Delay(5);
var value2 = sut.GetOrCreate("Key", () => ++ called);
Assert.Equal(1, called);
Assert.Equal(1, value1);
Assert.Equal(1, value2);
}
}