Duplicated test scenario I would like to test

WpfViewModelFirst.Tests/MainWindowViewModelTests.cs

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+using Moq;
+using WpfViewModelFirst.Part1;
+using WpfViewModelFirst.Part2;
+
+namespace WpfViewModelFirst.Tests
+{
+    public class MainWindowViewModelTests
+    {
+        [Fact]
+        public void Part1WillSetPart1ViewModelToCurrentViewModel()
+        {
+            Part1ViewModel part1ViewModel = new(() => _ = true);
+            Mock<IViewModelFactory> mockViewModelFactory = new Mock<IViewModelFactory>();
+            mockViewModelFactory.Setup(vmf => vmf.GetPart1ViewModel(It.IsAny<Action>()))
+                .Returns(part1ViewModel);
+            MainWindowViewModel main = new(mockViewModelFactory.Object);
+            main.Part1(null);
+            Assert.Equal(part1ViewModel, main.CurrentViewModel);
+        }
+        [Fact]
+        public void Part1CallbackIsSuccessfull()
+        {
+            Mock<IViewModelFactory> mockViewModelFactory = new Mock<IViewModelFactory>();
+            mockViewModelFactory.Setup(vmf => vmf.GetPart1ViewModel(It.IsAny<Action>()))
+                .Returns(() => new Part1ViewModel(() => Task.Delay(0)))
+                .Callback<Action>(c => c.Invoke());
+            mockViewModelFactory.Setup(vmf => vmf.GetPart2ViewModel())
+                .Returns(() => new Part2ViewModel());
+            MainWindowViewModel main = new(mockViewModelFactory.Object);
+            main.Part1(null);
+            Assert.IsType<Part2ViewModel>(main.CurrentViewModel);
+        }
+    }
+}

WpfViewModelFirst.Tests/Part1/Part1ViewModelTests.cs

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+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace WpfViewModelFirst.Tests.Part1
+{
+    public class Part1ViewModelTests
+    {
+
+    }
+}

WpfViewModelFirst.Tests/Part2/Part2ViewModelTests.cs

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+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace WpfViewModelFirst.Tests.Part2
+{
+    public class Part2ViewModelTests
+    {
+
+    }
+}

WpfViewModelFirst.Tests/Usings.cs

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+global using Xunit;

WpfViewModelFirst.Tests/WpfViewModelFirst.Tests.csproj

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+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net6.0-windows</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+
+    <IsPackable>false</IsPackable>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.3.0" />
+    <PackageReference Include="Moq" Version="4.18.2" />
+    <PackageReference Include="xunit" Version="2.4.2" />
+    <PackageReference Include="xunit.runner.visualstudio" Version="2.4.5">
+      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+      <PrivateAssets>all</PrivateAssets>
+    </PackageReference>
+    <PackageReference Include="coverlet.collector" Version="3.1.2">
+      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+      <PrivateAssets>all</PrivateAssets>
+    </PackageReference>
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\WpfViewModelFirst\WpfViewModelFirst.csproj" />
+  </ItemGroup>
+
+</Project>