public void IfTokenIsNotValidRefreshTokenShouldBeSuccessfully() { // Arrange var api = new WordsApi( new Configuration { ClientSecret = this.ClientSecret, ClientId = this.ClientId, ApiBaseUrl = "http://localhost:8081", AuthType = AuthType.OAuth2, DebugMode = true }); using (var stream = this.ToStream("content")) { var request = new ConvertDocumentRequest(stream, "txt"); api.ConvertDocument(request); Thread.Sleep(2000); stream.Flush(); stream.Position = 0; var traceListenerMock = new Mock <TraceListener>(); traceListenerMock.Setup(x => x.WriteLine(It.IsAny <string>())).Verifiable(); Trace.Listeners.Add(traceListenerMock.Object); try { // Act api.ConvertDocument(request); // Assert traceListenerMock.Verify(x => x.WriteLine(It.Is <string>(s => s.Contains("grant_type=refresh_token"))), Times.Once); traceListenerMock.Verify(x => x.WriteLine(It.IsAny <string>()), Times.AtLeast(2)); } finally { Trace.Listeners.Remove(traceListenerMock.Object); } } }