public async Task ChangeCurrentCulture_SameCultureThanSelected_DoNothing() { // Arrange var currentCulture = new CultureInfo("en"); var otherCulture = new CultureInfo("es"); _settingProvider.GetAvailableCultures().Returns(new List <CultureInfo> { currentCulture, otherCulture }); _settingProvider.GetCurrentCulture().Returns(currentCulture); await sut.Load(); var selectedLanguage = sut.AvailableLanguages.FirstOrDefault(x => x.Culture == currentCulture); // Act sut.ChangeCurrentCulture(selectedLanguage); // Assert _settingProvider.DidNotReceiveWithAnyArgs().SetCurrentCulture(null); _messageDialog.DidNotReceiveWithAnyArgs().Show(default(string), default(string)); }