[CmdPal][UnitTests] Add/Migrate unit test for Apps and Bookmarks extension (#41238)

<!-- Enter a brief description/summary of your PR here. What does it
fix/what does it change/how was it tested (even manually, if necessary)?
-->
## Summary of the Pull Request
1. Create Apps and Bookmarks ut project.
2. Refactor Apps and Bookmarks. And some interface in these extensions
to add a abstraction layer for testing purpose.
New interface list:
* ISettingsInterface
* IUWPApplication
* IAppCache
* IBookmarkDataSource
3. Add/Migrate some test case for Apps and Bookmarks extension

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## PR Checklist

- [x] Closes: #41239 #41240
- [x] **Communication:** I've discussed this with core contributors
already. If the work hasn't been agreed, this work might be rejected
- [x] **Tests:** Added/updated and all pass
- [ ] **Localization:** All end-user-facing strings can be localized
- [ ] **Dev docs:** Added/updated
- [ ] **New binaries:** Added on the required places
- [ ] [JSON for
signing](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ESRPSigning_core.json)
for new binaries
- [ ] [WXS for
installer](https://github.com/microsoft/PowerToys/blob/main/installer/PowerToysSetup/Product.wxs)
for new binaries and localization folder
- [ ] [YML for CI
pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/ci/templates/build-powertoys-steps.yml)
for new test projects
- [ ] [YML for signed
pipeline](https://github.com/microsoft/PowerToys/blob/main/.pipelines/release.yml)
- [ ] **Documentation updated:** If checked, please file a pull request
on [our docs
repo](https://github.com/MicrosoftDocs/windows-uwp/tree/docs/hub/powertoys)
and link it here: #xxx

<!-- Provide a more detailed description of the PR, other things fixed,
or any additional comments/features here -->
## Detailed Description of the Pull Request / Additional comments

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wherever possible, but list manual validation steps taken as well -->
## Validation Steps Performed

---------

Co-authored-by: Yu Leng <yuleng@microsoft.com>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Apps/AllAppsCommandProvider.cs

@@ -19,16 +19,23 @@ public partial class AllAppsCommandProvider : CommandProvider
 
     public static readonly AllAppsPage Page = new();
 
+    private readonly AllAppsPage _page;
     private readonly CommandItem _listItem;
 
     public AllAppsCommandProvider()
+        : this(Page)
     {
+    }
+
+    public AllAppsCommandProvider(AllAppsPage page)
+    {
+        _page = page ?? throw new ArgumentNullException(nameof(page));
         Id = WellKnownId;
         DisplayName = Resources.installed_apps;
         Icon = Icons.AllAppsIcon;
         Settings = AllAppsSettings.Instance.Settings;
 
-        _listItem = new(Page)
+        _listItem = new(_page)
         {
             Subtitle = Resources.search_installed_apps,
             MoreCommands = [new CommandContextItem(AllAppsSettings.Instance.Settings.SettingsPage)],
@@ -38,11 +45,11 @@ public partial class AllAppsCommandProvider : CommandProvider
         PinnedAppsManager.Instance.PinStateChanged += OnPinStateChanged;
     }
 
-    public override ICommandItem[] TopLevelCommands() => [_listItem, ..Page.GetPinnedApps()];
+    public override ICommandItem[] TopLevelCommands() => [_listItem, .._page.GetPinnedApps()];
 
     public ICommandItem? LookupApp(string displayName)
     {
-        var items = Page.GetItems();
+        var items = _page.GetItems();
 
         // We're going to do this search in two directions:
         // First, is this name a substring of any app...

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Apps/AllAppsPage.cs

@@ -2,6 +2,7 @@
 // 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.Collections.Generic;
 using System.Diagnostics;
 using System.Linq;
@@ -19,13 +20,20 @@ namespace Microsoft.CmdPal.Ext.Apps;
 public sealed partial class AllAppsPage : ListPage
 {
     private readonly Lock _listLock = new();
+    private readonly IAppCache _appCache;
 
     private AppItem[] allApps = [];
     private AppListItem[] unpinnedApps = [];
     private AppListItem[] pinnedApps = [];
 
     public AllAppsPage()
+        : this(AppCache.Instance.Value)
     {
+    }
+
+    public AllAppsPage(IAppCache appCache)
+    {
+        _appCache = appCache ?? throw new ArgumentNullException(nameof(appCache));
         this.Name = Resources.all_apps;
         this.Icon = Icons.AllAppsIcon;
         this.ShowDetails = true;
@@ -59,7 +67,7 @@ public sealed partial class AllAppsPage : ListPage
 
     private void BuildListItems()
     {
-        if (allApps.Length == 0 || AppCache.Instance.Value.ShouldReload())
+        if (allApps.Length == 0 || _appCache.ShouldReload())
         {
             lock (_listLock)
             {
@@ -75,7 +83,7 @@ public sealed partial class AllAppsPage : ListPage
 
                 this.IsLoading = false;
 
-                AppCache.Instance.Value.ResetReloadFlag();
+                _appCache.ResetReloadFlag();
 
                 stopwatch.Stop();
                 Logger.LogTrace($"{nameof(AllAppsPage)}.{nameof(BuildListItems)} took: {stopwatch.ElapsedMilliseconds} ms");
@@ -85,11 +93,11 @@ public sealed partial class AllAppsPage : ListPage
 
     private AppItem[] GetAllApps()
     {
-        var uwpResults = AppCache.Instance.Value.UWPs
+        var uwpResults = _appCache.UWPs
            .Where((application) => application.Enabled)
            .Select(app => app.ToAppItem());
 
-        var win32Results = AppCache.Instance.Value.Win32s
+        var win32Results = _appCache.Win32s
             .Where((application) => application.Enabled && application.Valid)
             .Select(app => app.ToAppItem());
 

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Apps/AllAppsSettings.cs

@@ -5,13 +5,14 @@
 using System;
 using System.Collections.Generic;
 using System.IO;
+using Microsoft.CmdPal.Ext.Apps.Helpers;
 using Microsoft.CmdPal.Ext.Apps.Programs;
 using Microsoft.CmdPal.Ext.Apps.Properties;
 using Microsoft.CommandPalette.Extensions.Toolkit;
 
 namespace Microsoft.CmdPal.Ext.Apps;
 
-public class AllAppsSettings : JsonSettingsManager
+public class AllAppsSettings : JsonSettingsManager, ISettingsInterface
 {
     private static readonly string _namespace = "apps";
 

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Apps/AppCache.cs

@@ -12,7 +12,7 @@ using Microsoft.CmdPal.Ext.Apps.Utils;
 
 namespace Microsoft.CmdPal.Ext.Apps;
 
-public sealed partial class AppCache : IDisposable
+public sealed partial class AppCache : IAppCache, IDisposable
 {
     private Win32ProgramFileSystemWatchers _win32ProgramRepositoryHelper;
 
@@ -24,7 +24,7 @@ public sealed partial class AppCache : IDisposable
 
     public IList<Win32Program> Win32s => _win32ProgramRepository.Items;
 
-    public IList<UWPApplication> UWPs => _packageRepository.Items;
+    public IList<IUWPApplication> UWPs => _packageRepository.Items;
 
     public static readonly Lazy<AppCache> Instance = new(() => new());
 

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Apps/Helpers/ISettingsInterface.cs

@@ -0,0 +1,22 @@
+// 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.Collections.Generic;
+
+namespace Microsoft.CmdPal.Ext.Apps.Helpers;
+
+public interface ISettingsInterface
+{
+    public bool EnableStartMenuSource { get; }
+
+    public bool EnableDesktopSource { get; }
+
+    public bool EnableRegistrySource { get; }
+
+    public bool EnablePathEnvironmentVariableSource { get; }
+
+    public List<string> ProgramSuffixes { get; }
+
+    public List<string> RunCommandSuffixes { get; }
+}

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Apps/IAppCache.cs

@@ -0,0 +1,37 @@
+// 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.Collections.Generic;
+using System.Threading.Tasks;
+using Microsoft.CmdPal.Ext.Apps.Programs;
+
+namespace Microsoft.CmdPal.Ext.Apps;
+
+/// <summary>
+/// Interface for application cache that provides access to Win32 and UWP applications.
+/// </summary>
+public interface IAppCache : IDisposable
+{
+    /// <summary>
+    /// Gets the collection of Win32 programs.
+    /// </summary>
+    IList<Win32Program> Win32s { get; }
+
+    /// <summary>
+    /// Gets the collection of UWP applications.
+    /// </summary>
+    IList<IUWPApplication> UWPs { get; }
+
+    /// <summary>
+    /// Determines whether the cache should be reloaded.
+    /// </summary>
+    /// <returns>True if cache should be reloaded, false otherwise.</returns>
+    bool ShouldReload();
+
+    /// <summary>
+    /// Resets the reload flag.
+    /// </summary>
+    void ResetReloadFlag();
+}

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Apps/Programs/IUWPApplication.cs

@@ -0,0 +1,43 @@
+// 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.Collections.Generic;
+using Microsoft.CommandPalette.Extensions;
+using Microsoft.CommandPalette.Extensions.Toolkit;
+
+namespace Microsoft.CmdPal.Ext.Apps.Programs;
+
+/// <summary>
+/// Interface for UWP applications to enable testing and mocking
+/// </summary>
+public interface IUWPApplication : IProgram
+{
+    string AppListEntry { get; set; }
+
+    string DisplayName { get; set; }
+
+    string UserModelId { get; set; }
+
+    string BackgroundColor { get; set; }
+
+    string EntryPoint { get; set; }
+
+    bool CanRunElevated { get; set; }
+
+    string LogoPath { get; set; }
+
+    LogoType LogoType { get; set; }
+
+    UWP Package { get; set; }
+
+    string LocationLocalized { get; }
+
+    string GetAppIdentifier();
+
+    List<IContextItem> GetCommands();
+
+    void UpdateLogoPath(Utils.Theme theme);
+
+    AppItem ToAppItem();
+}

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Apps/Programs/UWPApplication.cs

@@ -22,7 +22,7 @@ using Theme = Microsoft.CmdPal.Ext.Apps.Utils.Theme;
 namespace Microsoft.CmdPal.Ext.Apps.Programs;
 
 [Serializable]
-public class UWPApplication : IProgram
+public class UWPApplication : IUWPApplication
 {
     private static readonly IFileSystem FileSystem = new FileSystem();
     private static readonly IPath Path = FileSystem.Path;
@@ -517,7 +517,7 @@ public class UWPApplication : IProgram
         }
     }
 
-    internal AppItem ToAppItem()
+    public AppItem ToAppItem()
     {
         var app = this;
         var iconPath = app.LogoType != LogoType.Error ? app.LogoPath : string.Empty;

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Apps/Properties/AssemblyInfo.cs

@@ -0,0 +1,7 @@
+// 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.Runtime.CompilerServices;
+
+[assembly: InternalsVisibleTo("Microsoft.CmdPal.Ext.Apps.UnitTests")]

src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Apps/Storage/PackageRepository.cs

@@ -15,7 +15,7 @@ namespace Microsoft.CmdPal.Ext.Apps.Storage;
 /// A repository for storing packaged applications such as UWP apps or appx packaged desktop apps.
 /// This repository will also monitor for changes to the PackageCatalog and update the repository accordingly
 /// </summary>
-internal sealed partial class PackageRepository : ListRepository<UWPApplication>, IProgramRepository
+internal sealed partial class PackageRepository : ListRepository<IUWPApplication>, IProgramRepository
 {
     private readonly IPackageCatalog _packageCatalog;