Add re-exec tests for SSR + move NotFound sources into one directory.

Author: ilonatommy

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

@@ -87,6 +87,34 @@ public void CanRenderNotFoundPageAfterStreamingStarted()
         Browser.Equal("Default Not Found Page", () => Browser.Title);
     }
 
+    [Fact]
+    public void ProgrammaticNavigationToNotExistingPathReExecutesTo404()
+    {
+        Navigate($"{ServerPathBase}/reexecution/redirection-not-found?navigate-programmatically=true");
+        Assert404ReExecuted();
+    }
+
+    [Fact]
+    public void LinkNavigationToNotExistingPathReExecutesTo404()
+    {
+        Navigate($"{ServerPathBase}/reexecution/redirection-not-found");
+        Browser.Click(By.Id("link-to-not-existing-page"));
+        Assert404ReExecuted();
+    }
+
+    [Fact]
+    public void BrowserNavigationToNotExistingPathReExecutesTo404()
+    {
+        // non-existing path has to have re-execution middleware set up
+        // so it has to have "reexecution" prefix. Otherwise middleware mapping
+        // will not be activated, see configuration in Startup
+        Navigate($"{ServerPathBase}/reexecution/not-existing-page");
+        Assert404ReExecuted();
+    }
+
+    private void Assert404ReExecuted() =>
+        Browser.Equal("Welcome On Page Re-executed After Not Found Event", () => Browser.Exists(By.Id("test-info")).Text);
+
     [Theory]
     [InlineData(true)]
     [InlineData(false)]

src/Components/test/testassets/Components.TestServer/RazorComponentEndpointsNoInteractivityStartup.cs

@@ -48,19 +48,30 @@ public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
 
         app.Map("/subdir", app =>
         {
-            if (!env.IsDevelopment())
+            app.Map("/reexecution", reexecutionApp =>
             {
-                app.UseExceptionHandler("/Error", createScopeForErrors: true);
-            }
-
-            app.UseStaticFiles();
-            app.UseRouting();
-            RazorComponentEndpointsStartup<TRootComponent>.UseFakeAuthState(app);
-            app.UseAntiforgery();
-            app.UseEndpoints(endpoints =>
-            {
-                endpoints.MapRazorComponents<TRootComponent>();
+                reexecutionApp.UseStatusCodePagesWithReExecute("/not-found-reexecute", createScopeForErrors: true);
+                ConfigureSubdirPipeline(reexecutionApp, env);
             });
+
+            ConfigureSubdirPipeline(app, env);
+        });
+    }
+
+    private void ConfigureSubdirPipeline(IApplicationBuilder app, IWebHostEnvironment env)
+    {
+        if (!env.IsDevelopment())
+        {
+            app.UseExceptionHandler("/Error", createScopeForErrors: true);
+        }
+
+        app.UseStaticFiles();
+        app.UseRouting();
+        RazorComponentEndpointsStartup<TRootComponent>.UseFakeAuthState(app);
+        app.UseAntiforgery();
+        app.UseEndpoints(endpoints =>
+        {
+            endpoints.MapRazorComponents<TRootComponent>();
         });
     }
 }

src/Components/test/testassets/Components.TestServer/RazorComponentEndpointsStartup.cs

@@ -89,7 +89,7 @@ public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
         });
     }
 
-    protected virtual void ConfigureSubdirPipeline(IApplicationBuilder app, IWebHostEnvironment env)
+    private void ConfigureSubdirPipeline(IApplicationBuilder app, IWebHostEnvironment env)
     {
         WebAssemblyTestHelper.ServeCoopHeadersIfWebAssemblyThreadingEnabled(app);
 

src/Components/test/testassets/Components.TestServer/RazorComponents/Pages/NotFoundPage.razor renamed to src/Components/test/testassets/Components.TestServer/RazorComponents/Pages/NotFound/NotFoundPage.razor

@@ -0,0 +1,28 @@
+@page "/redirection-not-found"
+@page "/reexecution/redirection-not-found"
+@attribute [StreamRendering(false)]
+@inject NavigationManager NavigationManager
+
+<PageTitle>Original page</PageTitle>
+
+<p id="test-info">Any content</p>
+<a id="link-to-not-existing-page" href="@(_nonExistingPath)">
+    Go to not-existing-page
+</a>
+
+@code{
+    [Parameter]
+    [SupplyParameterFromQuery(Name = "navigate-programmatically")]
+    public bool? NavigateProgrammatically { get; set; }
+
+    private string? _nonExistingPath;
+
+    protected override void OnInitialized()
+    {
+        _nonExistingPath = $"{NavigationManager.BaseUri}not-existing-page";
+        if (NavigateProgrammatically == true)
+        {
+            NavigationManager.NavigateTo(_nonExistingPath);
+        }
+    }
+}