namespace R3.Tests.OperatorTests; public class IsEmptyTest { [Fact] public async Task Positive() { var range = Observable.Empty(); var task = range.IsEmptyAsync(); (await task).Should().BeTrue(); } [Fact] public async Task Negative() { var range = Observable.Return(0); var task = range.IsEmptyAsync(); (await task).Should().BeFalse(); } }