More tests revealing a problem with forwards/backwards action.

Author: ilonatommy

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

@@ -669,94 +669,132 @@ public void CanUpdateHrefOnLinkTagWithIntegrity()
     [InlineData(false, true)]
     [InlineData(true, true)]
     [InlineData(true, false)]
-    public void EnhancedNavigationScrollBehavesSameAsFullNavigation(bool enableStreaming, bool useEnhancedNavigation)
+    public void EnhancedNavigationScrollBehavesSameAsBrowserOnNavLinkNavigation(bool enableStreaming, bool useEnhancedNavigation)
     {
-        // This test checks if the navigation to other path moves the scroll to the top of the page,
-        // or to the beginning of a fragment, regardless of the previous scroll position,
-        // checks if going backwards and forwards preserves the scroll position
+        // This test checks if the navigation to another path moves the scroll to the top of the page,
+        // or to the beginning of a fragment, regardless of the previous scroll position
         string landingPageSuffix = enableStreaming ? "" : "-no-streaming";
         Navigate($"{ServerPathBase}/nav/testing-scroll{landingPageSuffix}");
         EnhancedNavigationTestUtil.SuppressEnhancedNavigation(this, shouldSuppress: !useEnhancedNavigation, skipNavigation: true);
 
+        // "scroll" page: scroll maximally down and go to "hash" page - we should land at the top of that page
         AssertWeAreOnScrollTestPage();
+        WaitStreamingRendersFullPage(enableStreaming);
 
-        // assert enhanced navigation is enabled/disabled, as requested
-        var elementForStalenessCheckOnScrollPage = Browser.Exists(By.TagName("html"));
+        // staleness check is used to assert enhanced navigation is enabled/disabled, as requested
+        var elementForStalenessCheckOnHashPage = Browser.Exists(By.TagName("html"));
 
         var jsExecutor = (IJavaScriptExecutor)Browser;
-        WaitFullPageLoaded();
         var maxScrollPosition = (long)jsExecutor.ExecuteScript("return document.documentElement.scrollHeight - window.innerHeight;");
-
-        // scroll maximally down and go to another page - we should land at the top of that page
         Browser.SetScrollY(maxScrollPosition);
         Browser.Exists(By.Id("do-navigation")).Click();
-        WaitFullPageLoaded();
-        AssertEnhancedNavigationOnHashPage();
+
+        // "hash" page: check if we landed at 0, then navigate to "scroll" 
+        WaitStreamingRendersFullPage(enableStreaming);
+        AssertEnhancedNavigation(useEnhancedNavigation, elementForStalenessCheckOnHashPage);
         AssertWeAreOnHashPage();
         Assert.Equal(0, Browser.GetScrollY());
-        var elementForStalenessCheckOnHashPage = Browser.Exists(By.TagName("html"));
-
+        var elementForStalenessCheckOnScrollPage = Browser.Exists(By.TagName("html"));
         var fragmentScrollPosition = (long)jsExecutor.ExecuteScript("return Math.round(document.getElementById('some-content').getBoundingClientRect().top + window.scrollY);");
+        Browser.Exists(By.Id("do-navigation")).Click();
 
-        // go back and check if the scroll position is preserved
-        Browser.Navigate().Back();
+        // "scroll" page: navigate to a fragment on another page - we should land at the beginning of the fragment
         AssertWeAreOnScrollTestPage();
-        WaitFullPageLoaded();
-        AssertEnhancedNavigationOnScrollPage();
+        WaitStreamingRendersFullPage(enableStreaming);
+        AssertEnhancedNavigation(useEnhancedNavigation, elementForStalenessCheckOnScrollPage);
 
-        // parts of page conditioned with showContent are showing with a delay - it affect the scroll position
-        // from some reason, scroll position differs by 1 pixel between enhanced and browser's navigation
-        var expectedMaxScrollPositionAfterBackwardsAction = useEnhancedNavigation ? maxScrollPosition: maxScrollPosition - 1;
-        Assert.Equal(expectedMaxScrollPositionAfterBackwardsAction, Browser.GetScrollY());
-
-        // navigate to a fragment on another page - we should land at the beginning of the fragment
         Browser.Exists(By.Id("do-navigation-with-fragment")).Click();
         AssertWeAreOnHashPage();
-        WaitFullPageLoaded();
-        AssertEnhancedNavigationOnHashPage();
+        WaitStreamingRendersFullPage(enableStreaming);
+        AssertEnhancedNavigation(useEnhancedNavigation, elementForStalenessCheckOnHashPage);
         var expectedFragmentScrollPosition = fragmentScrollPosition - 1;
         Assert.Equal(expectedFragmentScrollPosition, Browser.GetScrollY());
+    }
+
+    [Theory]
+    [InlineData(false, false)]
+    [InlineData(false, true)] // ToDo: Forwards -> line 772, Expected: 3270 Actual: 1400
+    [InlineData(true, true)] // ToDo: Forwards -> line 772, Expected: 2400 Actual: 412
+    [InlineData(true, false)] // ToDo: why it requires a special condition?
+    public void EnhancedNavigationScrollBehavesSameAsBrowserOnBackwardsForwardsAction(bool enableStreaming, bool useEnhancedNavigation)
+    {
+        // This test checks if the scroll position is preserved after backwards/forwards action
+        string landingPageSuffix = enableStreaming ? "" : "-no-streaming";
+        Navigate($"{ServerPathBase}/nav/testing-scroll{landingPageSuffix}");
+        EnhancedNavigationTestUtil.SuppressEnhancedNavigation(this, shouldSuppress: !useEnhancedNavigation, skipNavigation: true);
+
+        // "scroll" page: max scroll position on exiting it
+        AssertWeAreOnScrollTestPage();
+        WaitStreamingRendersFullPage(enableStreaming);
+
+        // staleness check is used to assert enhanced navigation is enabled/disabled, as requested
+        var elementForStalenessCheckOnHashPage = Browser.Exists(By.TagName("html"));
 
-        // go back to be able to go forward and check if the scroll position is preserved
+        var jsExecutor = (IJavaScriptExecutor)Browser;
+        var maxScrollPosition = (long)jsExecutor.ExecuteScript("return document.documentElement.scrollHeight - window.innerHeight;");
+        Browser.SetScrollY(maxScrollPosition);
+        Browser.Exists(By.Id("do-navigation")).Click();
+
+        // "hash" page: scroll position at fragment on exiting it
+        WaitStreamingRendersFullPage(enableStreaming);
+        AssertEnhancedNavigation(useEnhancedNavigation, elementForStalenessCheckOnHashPage);
+        AssertWeAreOnHashPage();
+        var elementForStalenessCheckOnScrollPage = Browser.Exists(By.TagName("html"));
+        var fragmentScrollPosition = (long)jsExecutor.ExecuteScript("return Math.round(document.getElementById('some-content').getBoundingClientRect().top + window.scrollY);");
+        Browser.SetScrollY(fragmentScrollPosition);
         Browser.Navigate().Back();
+
+        // "scroll" page: check if the scroll position is preserved at the bottom
         AssertWeAreOnScrollTestPage();
-        WaitFullPageLoaded();
-        AssertEnhancedNavigationOnScrollPage();
+        WaitStreamingRendersFullPage(enableStreaming);
+        AssertEnhancedNavigation(useEnhancedNavigation, elementForStalenessCheckOnScrollPage);
+
+        // from some reason, scroll position differs by 1 pixel between enhanced and browser's navigation
+        // browser's navigation is not precisely going backwards/forwards to the previous state
+        var expectedMaxScrollPositionAfterBackwardsAction = useEnhancedNavigation ? maxScrollPosition : maxScrollPosition - 1;
+        Assert.Equal(expectedMaxScrollPositionAfterBackwardsAction, Browser.GetScrollY());
 
+        // "scroll" page: go forwards to "hash" page, max scroll position on exiting
         Browser.Navigate().Forward();
         AssertWeAreOnHashPage();
-        WaitFullPageLoaded();
-        AssertEnhancedNavigationOnHashPage();
+        WaitStreamingRendersFullPage(enableStreaming);
+        AssertEnhancedNavigation(useEnhancedNavigation, elementForStalenessCheckOnHashPage);
+        // WHY is streaming with browser same as non-streaming with enhanced nav but different than non-streaming with browser?
+        var expectedFragmentScrollPosition = (useEnhancedNavigation || enableStreaming) ? fragmentScrollPosition : fragmentScrollPosition - 1;
         Assert.Equal(expectedFragmentScrollPosition, Browser.GetScrollY());
 
-        void AssertEnhancedNavigationOnHashPage() =>
-            AssertEnhancedNavigation(elementForStalenessCheckOnScrollPage);
-
-        void AssertEnhancedNavigationOnScrollPage()
-            => AssertEnhancedNavigation(elementForStalenessCheckOnHashPage);
+        // "hash" page: go back to "scroll" page
+        Browser.Navigate().Back();
+        AssertWeAreOnScrollTestPage();
+        WaitStreamingRendersFullPage(enableStreaming);
+        AssertEnhancedNavigation(useEnhancedNavigation, elementForStalenessCheckOnScrollPage);
+        var expectedMaxScrollPositionAfterSecondBackwardsAction = useEnhancedNavigation
+            ? expectedMaxScrollPositionAfterBackwardsAction
+            : expectedMaxScrollPositionAfterBackwardsAction - 1;
+        Assert.Equal(expectedMaxScrollPositionAfterSecondBackwardsAction, Browser.GetScrollY());
+    }
 
-        void AssertEnhancedNavigation(IWebElement elementForStalenessCheck)
-        {
-            bool enhancedNavigationDetected = !IsElementStale(elementForStalenessCheck);
-            Assert.Equal(useEnhancedNavigation, enhancedNavigationDetected);
-        }
+    private void AssertEnhancedNavigation(bool useEnhancedNavigation, IWebElement elementForStalenessCheck)
+    {
+        bool enhancedNavigationDetected = !IsElementStale(elementForStalenessCheck);
+        Assert.Equal(useEnhancedNavigation, enhancedNavigationDetected);
+    }
 
-        void AssertWeAreOnScrollTestPage()
-        {
-            Browser.Equal("Go back to me", () => Browser.Exists(By.Id("test-info")).Text);
-        }
+    private void AssertWeAreOnScrollTestPage()
+    {
+        Browser.Equal("Scroll tests landing page", () => Browser.Exists(By.Id("test-info")).Text);
+    }
 
-        void AssertWeAreOnHashPage()
-        {
-            Browser.Equal("Scroll to hash", () => Browser.Exists(By.Id("test-info")).Text);
-        }
+    private void AssertWeAreOnHashPage()
+    {
+        Browser.Equal("Scroll to hash", () => Browser.Exists(By.Id("test-info")).Text);
+    }
 
-        void WaitFullPageLoaded()
+    private void WaitStreamingRendersFullPage(bool enableStreaming)
+    {
+        if (enableStreaming)
         {
-            if (enableStreaming)
-            {
-                Browser.WaitForElementToBeVisible(By.Id("some-content"));
-            }
+            Browser.WaitForElementToBeVisible(By.Id("some-content"));
         }
     }
 

src/Components/test/testassets/Components.TestServer/RazorComponents/Pages/EnhancedNav/PageForScrollPositionTests.razor

@@ -4,7 +4,7 @@
 
 <PageTitle>Page for testing scroll position</PageTitle>
 
-<h1 id="test-info">Go back to me</h1>
+<h1 id="test-info">Scroll tests landing page</h1>
 
 <p>If you scroll down a long way, you'll find more content. We add it asynchronously via streaming rendering.</p>
 

src/Components/test/testassets/Components.TestServer/RazorComponents/Pages/EnhancedNav/PageForScrollPositionTestsNoStreaming.razor

@@ -4,7 +4,7 @@
 
 <PageTitle>Page for testing scroll position</PageTitle>
 
-<h1 id="test-info">Go back to me</h1>
+<h1 id="test-info">Scroll tests landing page</h1>
 
 <p>If you scroll down a long way, you'll find more content.</p>
 

src/Components/test/testassets/Components.TestServer/RazorComponents/Pages/EnhancedNav/PageForScrollingToHashNoStreaming.razor

@@ -13,7 +13,7 @@
     <div id="uri-on-page-load" style="display: none" data-value="@uriOnPageLoad"></div>
 </p>
 
-<div style="height: 2000px; border: 2px dashed red;">top spacer</div>
+<div style="height: 1000px; border: 2px dashed red;">top spacer</div>
 
 @if (showContent)
 {