Add unit tests for nested types that are not classes

Author: Sergio0694

tests/CommunityToolkit.Mvvm.UnitTests/Test_SourceGenerators.cs

@@ -0,0 +1,76 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System.ComponentModel.DataAnnotations;
+using CommunityToolkit.Mvvm.ComponentModel;
+using CommunityToolkit.Mvvm.Input;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+namespace CommunityToolkit.Mvvm.UnitTests;
+
+/// <summary>
+/// This class contains general unit tests for source generators, without a specific dependency on one.
+/// For instance, this can be used for tests that validate common generation helpers used by all generators.
+/// </summary>
+[TestClass]
+public partial class Test_SourceGenerators
+{
+    [TestMethod]
+    public void Test_SourceGenerators_NestedTypesThatAreNotJustClasses()
+    {
+        // This test just needs to compile, mostly
+        NestedStructType.NestedInterfaceType.MyViewModel model = new();
+
+        Assert.IsNull(model.Name);
+        Assert.IsTrue(model.TestCommand is IRelayCommand);
+    }
+
+    public partial struct NestedStructType
+    {
+        public partial interface NestedInterfaceType
+        {
+            [ObservableRecipient]
+            public partial class MyViewModel : ObservableValidator
+            {
+                [ObservableProperty]
+                [Required]
+                private string? name;
+
+                [ICommand]
+                private void Test()
+                {
+                }
+            }
+        }
+    }
+
+    [TestMethod]
+    public void Test_SourceGenerators_NestedTypesThatAreNotJustClassesAndWithGenerics()
+    {
+        // This test just needs to compile, mostly
+        NestedStructTypeWithGenerics<int, float>.NestedInterfaceType<string>.MyViewModel model = new();
+
+        Assert.IsNull(model.Name);
+        Assert.IsTrue(model.TestCommand is IRelayCommand);
+    }
+
+    public partial struct NestedStructTypeWithGenerics<T1, T2>
+        where T2 : struct
+    {
+        public partial interface NestedInterfaceType<TFoo>
+        {
+            [INotifyPropertyChanged]
+            public partial class MyViewModel
+            {
+                [ObservableProperty]
+                private string? name;
+
+                [ICommand]
+                private void Test()
+                {
+                }
+            }
+        }
+    }
+}