namespace R3.Tests.OperatorTests; public class ContainsTest { [Fact] public async Task Positive() { var range = Observable.Range(1, 10); var task = range.ContainsAsync(5); (await task).Should().BeTrue(); } [Fact] public async Task Negative() { var range = Observable.Range(1, 10); var task = range.ContainsAsync(0); (await task).Should().BeFalse(); } }