Allow to add sections to layouts

Modules/Layouting/Provider/LayoutBuilder.cs

@@ -89,6 +89,20 @@ public LayoutBuilder Add(IHandlerBuilder handler)
         return this;
     }
 
+    /// <summary>
+    /// Creates a new layout and registers it at the given path.
+    /// </summary>
+    /// <param name="section">The path of the section to be added</param>
+    /// <returns>The newly created section</returns>
+    public LayoutBuilder AddSection(string section)
+    {
+        var child = Layout.Create();
+
+        Add(section, child);
+
+        return child;
+    }
+
     public LayoutBuilder Add(IConcernBuilder concern)
     {
         _Concerns.Add(concern);

Testing/Acceptance/Modules/Layouting/SectionTests.cs

@@ -0,0 +1,31 @@
+using System.Net;
+using GenHTTP.Modules.IO;
+using GenHTTP.Modules.Layouting;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+namespace GenHTTP.Testing.Acceptance.Modules.Layouting;
+
+[TestClass]
+public class SectionTests
+{
+
+    [TestMethod]
+    [MultiEngineTest]
+    public async Task TestSection(TestEngine engine)
+    {
+        var app = Layout.Create();
+
+        var section = app.AddSection("section");
+
+        section.Index(Content.From(Resource.FromString("Hello World")));
+
+        await using var host = await TestHost.RunAsync(app, engine: engine);
+
+        using var response = await host.GetResponseAsync("/section/");
+
+        await response.AssertStatusAsync(HttpStatusCode.OK);
+
+        Assert.AreEqual("Hello World", await response.GetContentAsync());
+    }
+
+}