tests: add tests for copy button and heading links

test/Blog.Tests/EndToEnd/PostTests.cs

@@ -39,6 +39,43 @@ public class PostTests : BlogTest
     await Expect(content).ToBeVisibleAsync();
   }
 
+  [Test]
+  public async Task Post_WhenNavigatedToAndPostContainsCodeBlock_ItShouldDisplayCopyButton()
+  {
+    await Page.Context.GrantPermissionsAsync(["clipboard-read"]);
+
+    await Page.GotoAsync($"/{TestPostSlug}");
+    var copyButton = Page.GetByRole(AriaRole.Button, new() { Name = "Copy" });
+    await Expect(copyButton).ToBeVisibleAsync();
+
+    await copyButton.ClickAsync();
+    var clipboard = await Page.EvaluateAsync<string>("navigator.clipboard.readText()");
+    clipboard.Should().Be(
+      """
+      def greet(name):
+        print(f"Hello, {name}!")
+
+      greet("World")
+      """
+    );
+
+    await Page.Context.ClearPermissionsAsync();
+  }
+
+  [Test]
+  public async Task Post_WhenNavigatedToAndPostContainsHeadings_ItShouldDisplayLinkToHeading()
+  {
+    await Page.GotoAsync($"/{TestPostSlug}");
+    var heading = Page.GetByRole(AriaRole.Heading, new() { Name = "Text Formatting" });
+    await Expect(heading).ToBeVisibleAsync();
+
+    var link = heading.GetByRole(AriaRole.Link);
+    await Expect(link).ToBeVisibleAsync();
+
+    await link.ClickAsync();
+    Page.Url.Should().EndWith("#text-formatting");
+  }
+
   [Test]
   public async Task Post_WhenNavigatedToAndPostDoesNotExist_ItShouldDisplay404()
   {