[Fixes #2157] Added additional functional tests for TempData

src/Microsoft.AspNet.Mvc.Core/SessionStateTempDataProvider.cs

@@ -43,6 +43,12 @@ namespace Microsoft.AspNet.Mvc
                 // If we got it from Session, remove it so that no other request gets it
                 session.Remove(TempDataSessionStateKey);
             }
+            else
+            {
+                // Since we call Save() after the response has been sent, we need to initialize an empty session
+                // so that it is established before the headers are sent.
+                session[TempDataSessionStateKey] = new byte[] { };
+            }
 
             return tempDataDictionary;
         }

test/Microsoft.AspNet.Mvc.Core.Test/SessionStateTempDataProviderTest.cs

@@ -90,6 +90,7 @@ namespace Microsoft.AspNet.Mvc
             if (sessionEnabled)
             {
                 httpContext.Setup(h => h.GetFeature<ISessionFeature>()).Returns(Mock.Of<ISessionFeature>());
+                httpContext.Setup(h => h.Session[It.IsAny<string>()]);
             }
             return httpContext.Object;
         }

test/Microsoft.AspNet.Mvc.FunctionalTests/TempDataTest.cs

@@ -18,6 +18,39 @@ namespace Microsoft.AspNet.Mvc.FunctionalTests
         private readonly Action<IApplicationBuilder> _app = new TempDataWebSite.Startup().Configure;
         private readonly Action<IServiceCollection> _configureServices = new TempDataWebSite.Startup().ConfigureServices;
 
+        [Fact]
+        public async Task TempData_PersistsJustForNextRequest()
+        {
+            // Arrange
+            var server = TestHelper.CreateServer(_app, SiteName, _configureServices);
+            var client = server.CreateClient();
+            var nameValueCollection = new List<KeyValuePair<string, string>>
+            {
+                new KeyValuePair<string, string>("value", "Foo"),
+            };
+            var content = new FormUrlEncodedContent(nameValueCollection);
+
+            // Act 1
+            var response = await client.PostAsync("/Home/SetTempData", content);
+
+            // Assert 1
+            Assert.Equal(HttpStatusCode.OK, response.StatusCode);
+
+            // Act 2
+            response = await client.SendAsync(GetRequest("Home/GetTempData", response));
+
+            // Assert 2
+            Assert.Equal(HttpStatusCode.OK, response.StatusCode);
+            var body = await response.Content.ReadAsStringAsync();
+            Assert.Equal("Foo", body);
+
+            // Act 3
+            response = await client.SendAsync(GetRequest("Home/GetTempData", response));
+
+            // Assert 3
+            Assert.Equal(HttpStatusCode.NoContent, response.StatusCode);
+        }
+
         [Fact]
         public async Task ViewRendersTempData()
         {
@@ -38,5 +71,85 @@ namespace Microsoft.AspNet.Mvc.FunctionalTests
             var body = await response.Content.ReadAsStringAsync();
             Assert.Equal("Foo", body);
         }
+
+        [Fact]
+        public async Task Redirect_RetainsTempData_EvenIfAccessed()
+        {
+            // Arrange
+            var server = TestHelper.CreateServer(_app, SiteName, _configureServices);
+            var client = server.CreateClient();
+            var nameValueCollection = new List<KeyValuePair<string, string>>
+            {
+                new KeyValuePair<string, string>("value", "Foo"),
+            };
+            var content = new FormUrlEncodedContent(nameValueCollection);
+
+            // Act 1
+            var response = await client.PostAsync("/Home/SetTempData", content);
+
+            // Assert 1
+            Assert.Equal(HttpStatusCode.OK, response.StatusCode);
+
+            // Act 2
+            var redirectResponse = await client.SendAsync(GetRequest("/Home/GetTempDataAndRedirect", response));
+
+            // Assert 2
+            Assert.Equal(HttpStatusCode.Redirect, redirectResponse.StatusCode);
+
+            // Act 3
+            response = await client.SendAsync(GetRequest(redirectResponse.Headers.Location.ToString(), response));
+
+            // Assert 3
+            Assert.Equal(HttpStatusCode.OK, response.StatusCode);
+            var body = await response.Content.ReadAsStringAsync();
+            Assert.Equal("Foo", body);
+        }
+
+        [Fact]
+        public async Task Peek_RetainsTempData()
+        {
+            // Arrange
+            var server = TestHelper.CreateServer(_app, SiteName, _configureServices);
+            var client = server.CreateClient();
+            var nameValueCollection = new List<KeyValuePair<string, string>>
+            {
+                new KeyValuePair<string, string>("value", "Foo"),
+            };
+            var content = new FormUrlEncodedContent(nameValueCollection);
+
+            // Act 1
+            var response = await client.PostAsync("/Home/SetTempData", content);
+
+            // Assert 1
+            Assert.Equal(HttpStatusCode.OK, response.StatusCode);
+
+            // Act 2
+            var peekResponse = await client.SendAsync(GetRequest("/Home/PeekTempData", response));
+
+            // Assert 2
+            Assert.Equal(HttpStatusCode.OK, peekResponse.StatusCode);
+            var body = await peekResponse.Content.ReadAsStringAsync();
+            Assert.Equal("Foo", body);
+
+            // Act 3
+            var getResponse = await client.SendAsync(GetRequest("/Home/GetTempData", response));
+
+            // Assert 3
+            Assert.Equal(HttpStatusCode.OK, getResponse.StatusCode);
+            body = await getResponse.Content.ReadAsStringAsync();
+            Assert.Equal("Foo", body);
+        }
+
+        private HttpRequestMessage GetRequest(string path, HttpResponseMessage response)
+        {
+            var request = new HttpRequestMessage(HttpMethod.Get, path);
+            IEnumerable<string> values;
+            if (response.Headers.TryGetValues("Set-Cookie", out values))
+            {
+                request.Headers.Add("Cookie", values);
+            }
+
+            return request;
+        }
     }
 }

test/WebSites/TempDataWebSite/Controllers/HomeController.cs

@@ -17,5 +17,29 @@ namespace TempDataWebSite.Controllers
             TempData["key"] = value;
             return View();
         }
+
+        public IActionResult SetTempData(string value)
+        {
+            TempData["key"] = value;
+            return Content(value);
+        }
+
+        public IActionResult GetTempDataAndRedirect()
+        {
+            var value = TempData["key"];
+            return RedirectToAction("GetTempData");
+        }
+
+        public string GetTempData()
+        {
+            var value = TempData["key"];
+            return value?.ToString();
+        }
+
+        public IActionResult PeekTempData()
+        {
+            var peekValue = TempData.Peek("key");
+            return Content(peekValue.ToString());
+        }
     }
 }