Solve merge conflict: hard stop in redirection and deferred stop in 404.

Author: ilonatommy

src/Components/Endpoints/src/Rendering/EndpointHtmlRenderer.EventDispatch.cs

@@ -93,7 +93,11 @@ private async Task SetNotFoundResponseAsync(string baseUri)
             _httpContext.Response.StatusCode = StatusCodes.Status404NotFound;
             _httpContext.Response.ContentType = null;
         }
-        SignalRendererToFinishRendering();
+
+        // When the application triggers a NotFound event, we continue rendering the current batch.
+        // However, after completing this batch, we do not want to process any further UI updates,
+        // as we are going to return a 404 status and discard the UI updates generated so far.
+        SignalRendererToFinishRenderingAfterCurrentBatch();
     }
 
     private async Task OnNavigateTo(string uri)

src/Components/Endpoints/src/Rendering/EndpointHtmlRenderer.cs

@@ -183,12 +183,28 @@ protected override void AddPendingTask(ComponentState? componentState, Task task
         base.AddPendingTask(componentState, task);
     }
 
-    protected override void SignalRendererToFinishRendering()
+    private void SignalRendererToFinishRenderingAfterCurrentBatch()
     {
+        // sets a deferred stop on the renderer, which will have an effect after the current batch is completed
         _rendererIsStopped = true;
+    }
+
+    protected override void SignalRendererToFinishRendering()
+    {
+        SignalRendererToFinishRenderingAfterCurrentBatch();
+        // sets a hard stop on the renderer, which will have an effect immediately
         base.SignalRendererToFinishRendering();
     }
 
+    protected override void ProcessPendingRender()
+    {
+        if (_rendererIsStopped)
+        {
+            return;
+        }
+        base.ProcessPendingRender();
+    }
+
     // For tests only
     internal Task? NonStreamingPendingTasksCompletion;
 

src/Components/test/E2ETest/ServerRenderingTests/NoInteractivityTest.cs

@@ -106,4 +106,17 @@ public void CanRenderNotFoundPageNoStreaming(bool useCustomNotFoundPage)
             Assert.Contains("There's nothing here", bodyText);
         }
     }
+
+    [Theory]
+    [InlineData(true)]
+    [InlineData(false)]
+    public void CanRenderNotFoundPageWithStreaming(bool useCustomNotFoundPage)
+    {
+        // when streaming started, we always render page under "not-found" path
+        string query = useCustomNotFoundPage ? "?useCustomNotFoundPage=true" : "";
+        Navigate($"{ServerPathBase}/streaming-set-not-found{query}");
+
+        string expectedTitle = "Default Not Found Page";
+        Browser.Equal(expectedTitle, () => Browser.Title);
+    }
 }

src/Components/test/E2ETest/ServerRenderingTests/StatusCodePagesTest.cs

@@ -22,21 +22,18 @@ public class StatusCodePagesTest(BrowserFixture browserFixture, BasicTestAppServ
 {
 
     [Theory]
-    [InlineData(false, true)]
-    [InlineData(true, false)]
     [InlineData(false, false)]
-    public void StatusCodePagesWithReExecution(bool setNotFound, bool streaming)
+    [InlineData(true, false)]
+    [InlineData(true, true)]
+    public void StatusCodePagesWithReExecution(bool streaming, bool responseStarted)
     {
         string streamingPath = streaming ? "streaming-" : "";
-        Navigate($"{ServerPathBase}/reexecution/{streamingPath}set-not-found?shouldSet={setNotFound}");
+        Navigate($"{ServerPathBase}/reexecution/{streamingPath}set-not-found?responseStarted={responseStarted}");
 
         // streaming when response started does not re-execute
-        string expectedTitle = streaming
+        string expectedTitle = responseStarted
             ? "Default Not Found Page"
-            : setNotFound
-                ? "Re-executed page"
-                : "Original page";
+            : "Re-executed page";
         Browser.Equal(expectedTitle, () => Browser.Title);
     }
-
 }

src/Components/test/testassets/Components.TestServer/RazorComponents/Pages/PageThatSetsNotFound.razor

@@ -10,11 +10,12 @@
 @code{
     [Parameter]
     [SupplyParameterFromQuery(Name = "shouldSet")]
-    public bool ShouldSet { get; set; } = true;
+    public bool? ShouldSet { get; set; }
 
     protected override void OnInitialized()
     {
-        if (ShouldSet)
+        bool shouldSet = ShouldSet ?? true;
+        if (shouldSet)
         {
             NavigationManager.NotFound();
         }

src/Components/test/testassets/Components.TestServer/RazorComponents/Pages/StreamingRendering/StreamingSetNotFound.razor

@@ -1,12 +1,30 @@
+@page "/reexecution/streaming-set-not-found"
 @page "/streaming-set-not-found"
 @attribute [StreamRendering]
 @inject NavigationManager NavigationManager
 
-@code{
+@code {
+    [Parameter]
+    [SupplyParameterFromQuery(Name = "shouldSet")]
+    public bool? ShouldSet { get; set; }
+
+    [Parameter]
+    [SupplyParameterFromQuery(Name = "responseStarted")]
+    public bool? ResponseStarted { get; set; }
+
     protected override async Task OnInitializedAsync()
     {
-        // Simulate some delay before triggering NotFound to start streaming response
-        await Task.Yield();
-        NavigationManager.NotFound();
+        bool shouldSet = ShouldSet ?? true;
+        bool responseStarted = ResponseStarted ?? true;
+        if (responseStarted)
+        {
+            // Simulate some delay before triggering NotFound to start streaming response
+            await Task.Yield();
+        }
+
+        if (shouldSet)
+        {
+            NavigationManager.NotFound();
+        }
     }
-}
+}