Allow to add sections to layouts

Modules/Layouting/MultiSegmentSupport.cs

@@ -22,35 +22,53 @@ public static LayoutBuilder Add(this LayoutBuilder builder, string[] segments, I
             return builder.Add(handler);
         }
 
-        var current = builder;
+        var last = builder.AddSegments(segments[..^1]);
+
+        last.Add(segments[^1], handler);
+
+        return builder;
+    }
 
-        for (var i = 0; i < segments.Length - 1; i++)
+    /// <summary>
+    /// Adds all the given segments to the layout and returns the
+    /// last one.
+    /// </summary>
+    /// <param name="builder">The layout to add the sections to</param>
+    /// <param name="segments">The segments to be added</param>
+    /// <returns>The last created layout</returns>
+    /// <exception cref="InvalidOperationException">Thrown if there are incompatible handlers already registered at a segment</exception>
+    public static LayoutBuilder AddSegments(this LayoutBuilder builder, params string[] segments)
+    {
+        if (segments.Length == 0)
         {
-            var segment = segments[i];
+            return builder;
+        }
+
+        var current = builder;
 
-            if (current.RoutedHandlers.TryGetValue(segment, out var existing))
+        foreach (var section in segments)
+        {
+            if (current.RoutedHandlers.TryGetValue(section, out var existing))
             {
                 if (existing is LayoutBuilder existingLayout)
                 {
                     current = existingLayout;
                 }
                 else
                 {
-                    throw new InvalidOperationException($"Existing segment '{segment}' is no layout");
+                    throw new InvalidOperationException($"Existing section '{section}' is no layout");
                 }
             }
             else
             {
                 var newLayout = Layout.Create();
 
-                current.Add(segment, newLayout);
+                current.Add(section, newLayout);
                 current = newLayout;
             }
         }
 
-        current.Add(segments[^1], handler);
-
-        return builder;
+        return current;
     }
 
 }

Modules/Layouting/Provider/LayoutBuilder.cs

@@ -95,6 +95,20 @@ public LayoutBuilder Add(IConcernBuilder concern)
         return this;
     }
 
+    /// <summary>
+    /// Creates a new layout and registers it at the given path.
+    /// </summary>
+    /// <param name="section">The path of the segment to be added</param>
+    /// <returns>The newly created segment</returns>
+    public LayoutBuilder AddSegment(string segment)
+    {
+        var child = Layout.Create();
+
+        Add(segment, child);
+
+        return child;
+    }
+
     public IHandler Build()
     {
         var routed = RoutedHandlers.ToDictionary(kv => kv.Key, kv => kv.Value.Build());

Testing/Acceptance/Modules/Layouting/MultiSegmentTests.cs

@@ -71,4 +71,20 @@ public void TestSegmentOccupied()
         });
     }
 
+    [TestMethod]
+    [MultiEngineTest]
+    public async Task TestEmpty(TestEngine engine)
+    {
+        var app = Layout.Create()
+                        .Add([], Content.From(Resource.FromString("Hello Empty!")));
+
+        await using var host = await TestHost.RunAsync(app, engine: engine);
+
+        using var response = await host.GetResponseAsync();
+
+        await response.AssertStatusAsync(HttpStatusCode.OK);
+
+        Assert.AreEqual("Hello Empty!", await response.GetContentAsync());
+    }
+
 }

Testing/Acceptance/Modules/Layouting/SegmentTests.cs

@@ -0,0 +1,50 @@
+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 SegmentTests
+{
+
+    [TestMethod]
+    [MultiEngineTest]
+    public async Task TestSegment(TestEngine engine)
+    {
+        var app = Layout.Create();
+
+        var section = app.AddSegment("segment");
+
+        section.Index(Content.From(Resource.FromString("Hello World")));
+
+        await using var host = await TestHost.RunAsync(app, engine: engine);
+
+        using var response = await host.GetResponseAsync("/segment/");
+
+        await response.AssertStatusAsync(HttpStatusCode.OK);
+
+        Assert.AreEqual("Hello World", await response.GetContentAsync());
+    }
+
+    [TestMethod]
+    [MultiEngineTest]
+    public async Task TestMultiSegment(TestEngine engine)
+    {
+        var app = Layout.Create();
+
+        var section = app.AddSegments(["one", "two"]);
+
+        section.Index(Content.From(Resource.FromString("Hello World")));
+
+        await using var host = await TestHost.RunAsync(app, engine: engine);
+
+        using var response = await host.GetResponseAsync("/one/two/");
+
+        await response.AssertStatusAsync(HttpStatusCode.OK);
+
+        Assert.AreEqual("Hello World", await response.GetContentAsync());
+    }
+
+}