tests/Web.Tests/WebAppTests.cs

@@ -0,0 +1,61 @@
+using Domain;
+using System.Reflection;
+using static TestData.ClientBuilder;
+using static TestData.OrderBuilder;
+
+namespace Web.Tests;
+
+/// <summary>The WebApp consumes only DTOs; persistence types are excluded at compile time (no Web → Db project reference).</summary>
+public class WebAppTests
+{
+    // The WebApp's public API references no domain type (reflection).
+    private static readonly Type[] BannedTypes = [typeof(Client), typeof(Order)];
+
+    private static IEnumerable<Type> TypeAndArguments(Type t)
+    {
+        yield return t;
+        if (t.IsGenericType)
+            foreach (var arg in t.GetGenericArguments())
+                foreach (var nested in TypeAndArguments(arg))
+                    yield return nested;
+        if (t.IsArray && t.GetElementType() is { } elem)
+            foreach (var nested in TypeAndArguments(elem))
+                yield return nested;
+    }
+
+    [Fact]
+    public void WebApp_public_api_references_no_domain_types()
+    {
+        var app = typeof(WebApp);
+        var banned = BannedTypes.ToList();
+
+        foreach (var m in app.GetMethods(BindingFlags.Public | BindingFlags.Instance | BindingFlags.Static))
+        {
+            var signature = m.GetParameters()
+                .Select(p => p.ParameterType)
+                .Append(m.ReturnType)
+                .ToList();
+            foreach (var t in signature.SelectMany(TypeAndArguments))
+                Assert.False(banned.Contains(t),
+                    $"WebApp.{m.Name}({string.Join(", ", signature)}) references banned type {t}");
+        }
+
+        foreach (var p in app.GetProperties(BindingFlags.Public | BindingFlags.Instance | BindingFlags.Static))
+            foreach (var t in TypeAndArguments(p.PropertyType))
+                Assert.False(banned.Contains(t),
+                    $"WebApp.{p.Name} references banned type {t}");
+    }
+
+    [Fact]
+    public void WebApp_consumes_dtos()
+    {
+        var app = new WebApp();
+        var order = ValidOrder().WithId(Guid.NewGuid()).WithDescription("order one").WithTotal(150_00).Build();
+        var client = ValidClient().WithId(Guid.NewGuid()).WithName("Acme").WithOrder(order).Build();
+
+        var view = app.ShowClient(DtoMappers.ToClientDto(client));
+
+        Assert.Contains("Acme", view);
+        Assert.Contains("order one", view);
+    }
+}