[Settings] Migrate File Explorer Preview Settings (#5785)

* added MSTest project

* migrate file explorer preview settings

* updated test file

* fixed build

src/core/Microsoft.PowerToys.Settings.UI.UnitTests/ViewModelTests/PowerPreview.cs

@@ -0,0 +1,105 @@
+// Copyright (c) Microsoft Corporation
+// The Microsoft Corporation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+using System;
+using System.IO;
+using System.Text.Json;
+using Microsoft.PowerToys.Settings.UI.Lib;
+using Microsoft.PowerToys.Settings.UI.Lib.ViewModels;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+namespace ViewModelTests
+{
+    [TestClass]
+    public class PowerPreview
+    {
+        public const string Module = "Test\\File Explorer";
+
+        [TestInitialize]
+        public void Setup()
+        {
+            // initialize creation of test settings file.
+            GeneralSettings generalSettings = new GeneralSettings();
+            PowerPreviewSettings powerpreview = new PowerPreviewSettings();
+
+            SettingsUtils.SaveSettings(generalSettings.ToJsonString());
+            SettingsUtils.SaveSettings(powerpreview.ToJsonString(), powerpreview.Name);
+        }
+
+        [TestCleanup]
+        public void CleanUp()
+        {
+            // delete folder created.
+            string generalSettings_file_name = string.Empty;
+            if (SettingsUtils.SettingsFolderExists(generalSettings_file_name))
+            {
+                DeleteFolder(generalSettings_file_name);
+            }
+
+            if (SettingsUtils.SettingsFolderExists(Module))
+            {
+                DeleteFolder(Module);
+            }
+        }
+
+        public void DeleteFolder(string powertoy)
+        {
+            Directory.Delete(Path.Combine(SettingsUtils.LocalApplicationDataFolder(), $"Microsoft\\PowerToys\\{powertoy}"), true);
+        }
+
+        [TestMethod]
+        public void SVGRenderIsEnabled_ShouldPrevHandler_WhenSuccessful()
+        {
+            // Assert
+            Func<string, int> SendMockIPCConfigMSG = msg =>
+            {
+                SndModuleSettings<SndPowerPreviewSettings> snd = JsonSerializer.Deserialize<SndModuleSettings<SndPowerPreviewSettings>>(msg);
+                Assert.IsTrue(snd.powertoys.FileExplorerPreviewSettings.Properties.EnableSvgPreview);
+                return 0;
+            };
+
+            // arrange
+            PowerPreviewViewModel viewModel = new PowerPreviewViewModel(SendMockIPCConfigMSG, Module);
+
+            // act
+            viewModel.SVGRenderIsEnabled = true;
+        }
+
+        [TestMethod]
+        public void SVGThumbnailIsEnabled_ShouldPrevHandler_WhenSuccessful()
+        {
+            // Assert
+            Func<string, int> SendMockIPCConfigMSG = msg =>
+            {
+                SndModuleSettings<SndPowerPreviewSettings> snd = JsonSerializer.Deserialize<SndModuleSettings<SndPowerPreviewSettings>>(msg);
+                Assert.IsTrue(snd.powertoys.FileExplorerPreviewSettings.Properties.EnableSvgThumbnail);
+                return 0;
+            };
+
+            // arrange
+            PowerPreviewViewModel viewModel = new PowerPreviewViewModel(SendMockIPCConfigMSG, Module);
+
+            // act
+            viewModel.SVGThumbnailIsEnabled = true;
+        }
+
+        [TestMethod]
+        public void MDRenderIsEnabled_ShouldPrevHandler_WhenSuccessful()
+        {
+            // Assert
+            Func<string, int> SendMockIPCConfigMSG = msg =>
+            {
+                SndModuleSettings<SndPowerPreviewSettings> snd = JsonSerializer.Deserialize<SndModuleSettings<SndPowerPreviewSettings>>(msg);
+                Assert.IsTrue(snd.powertoys.FileExplorerPreviewSettings.Properties.EnableMdPreview);
+                return 0;
+            };
+
+            // arrange
+            PowerPreviewViewModel viewModel = new PowerPreviewViewModel(SendMockIPCConfigMSG, Module);;
+
+            // act
+            viewModel.MDRenderIsEnabled = true;
+        }
+    }
+}