[CmdNotFound]Support PowerShell Preview installation (#32034)

* [CommandNotFound] extending to detect PowerShellPreview installations

* Re-implementing directory search, where the PowerShell Preview is
installed

* Re-implementing preview or normal powershell executable usage

src/settings-ui/Settings.UI/ViewModels/CmdNotFoundViewModel.cs

@@ -3,8 +3,10 @@
 // See the LICENSE file in the project root for more information.
 
 using System;
+using System.Collections.Generic;
 using System.Diagnostics;
 using System.IO;
+using System.Linq;
 using System.Reflection;
 using System.Runtime.InteropServices;
 using global::PowerToys.GPOWrapper;
@@ -76,6 +78,9 @@ namespace Microsoft.PowerToys.Settings.UI.ViewModels
 
         private bool _isPowerShell7Detected;
 
+        private bool isPowerShellPreviewDetected;
+        private string powerShellPreviewPath;
+
         public bool IsPowerShell7Detected
         {
             get => _isPowerShell7Detected;
@@ -129,6 +134,18 @@ namespace Microsoft.PowerToys.Settings.UI.ViewModels
             get => RuntimeInformation.OSArchitecture == System.Runtime.InteropServices.Architecture.Arm64;
         }
 
+        public string RunPowerShellOrPreviewScript(string powershellExecutable, string powershellArguments, bool hidePowerShellWindow = false)
+        {
+            if (isPowerShellPreviewDetected)
+            {
+                return RunPowerShellScript(Path.Combine(powerShellPreviewPath, "pwsh-preview.cmd"), powershellArguments, hidePowerShellWindow);
+            }
+            else
+            {
+                return RunPowerShellScript(powershellExecutable, powershellArguments, hidePowerShellWindow);
+            }
+        }
+
         public string RunPowerShellScript(string powershellExecutable, string powershellArguments, bool hidePowerShellWindow = false)
         {
             string outputLog = string.Empty;
@@ -160,6 +177,7 @@ namespace Microsoft.PowerToys.Settings.UI.ViewModels
 
         public void CheckCommandNotFoundRequirements()
         {
+            isPowerShellPreviewDetected = false;
             var ps1File = AssemblyDirectory + "\\Assets\\Settings\\Scripts\\CheckCmdNotFoundRequirements.ps1";
             var arguments = $"-NoProfile -NonInteractive -ExecutionPolicy Unrestricted -File \"{ps1File}\"";
             var result = RunPowerShellScript("pwsh.exe", arguments, true);
@@ -179,6 +197,33 @@ namespace Microsoft.PowerToys.Settings.UI.ViewModels
                 IsPowerShell7Detected = false;
             }
 
+            if (!IsPowerShell7Detected)
+            {
+                // powerShell Preview might be installed, check it.
+                try
+                {
+                    // we have to search for the directory where the PowerShell preview command is located. It is added to the PATH environment variable, so we have to search for it there
+                    foreach (string pathCandidate in Environment.GetEnvironmentVariable("PATH").Split(';'))
+                    {
+                        if (File.Exists(Path.Combine(pathCandidate, "pwsh-preview.cmd")))
+                        {
+                            result = RunPowerShellScript(Path.Combine(pathCandidate, "pwsh-preview.cmd"), arguments, true);
+                            if (result.Contains("PowerShell 7.4 or greater detected."))
+                            {
+                                isPowerShellPreviewDetected = true;
+                                IsPowerShell7Detected = true;
+                                powerShellPreviewPath = pathCandidate;
+                                break;
+                            }
+                        }
+                    }
+                }
+                catch (Exception)
+                {
+                    // nothing to do. No additional PowerShell installation found
+                }
+            }
+
             if (result.Contains("WinGet Client module detected."))
             {
                 IsWinGetClientModuleDetected = true;
@@ -204,7 +249,7 @@ namespace Microsoft.PowerToys.Settings.UI.ViewModels
         {
             var ps1File = AssemblyDirectory + "\\Assets\\Settings\\Scripts\\InstallPowerShell7.ps1";
             var arguments = $"-NoProfile -ExecutionPolicy Unrestricted -File \"{ps1File}\"";
-            var result = RunPowerShellScript("powershell.exe", arguments);
+            var result = RunPowerShellOrPreviewScript("powershell.exe", arguments);
             if (result.Contains("Powershell 7 successfully installed."))
             {
                 IsPowerShell7Detected = true;
@@ -220,7 +265,7 @@ namespace Microsoft.PowerToys.Settings.UI.ViewModels
         {
             var ps1File = AssemblyDirectory + "\\Assets\\Settings\\Scripts\\InstallWinGetClientModule.ps1";
             var arguments = $"-NoProfile -ExecutionPolicy Unrestricted -File \"{ps1File}\"";
-            var result = RunPowerShellScript("pwsh.exe", arguments);
+            var result = RunPowerShellOrPreviewScript("pwsh.exe", arguments);
             if (result.Contains("WinGet Client module detected."))
             {
                 IsWinGetClientModuleDetected = true;
@@ -237,7 +282,7 @@ namespace Microsoft.PowerToys.Settings.UI.ViewModels
         {
             var ps1File = AssemblyDirectory + "\\Assets\\Settings\\Scripts\\EnableModule.ps1";
             var arguments = $"-NoProfile -ExecutionPolicy Unrestricted -File \"{ps1File}\" -scriptPath \"{AssemblyDirectory}\\..\"";
-            var result = RunPowerShellScript("pwsh.exe", arguments);
+            var result = RunPowerShellOrPreviewScript("pwsh.exe", arguments);
 
             if (result.Contains("Module is already registered in the profile file.") || result.Contains("Module was successfully registered in the profile file."))
             {
@@ -252,7 +297,7 @@ namespace Microsoft.PowerToys.Settings.UI.ViewModels
         {
             var ps1File = AssemblyDirectory + "\\Assets\\Settings\\Scripts\\DisableModule.ps1";
             var arguments = $"-NoProfile -ExecutionPolicy Unrestricted -File \"{ps1File}\"";
-            var result = RunPowerShellScript("pwsh.exe", arguments);
+            var result = RunPowerShellOrPreviewScript("pwsh.exe", arguments);
 
             if (result.Contains("Removed the Command Not Found reference from the profile file.") || result.Contains("No instance of Command Not Found was found in the profile file."))
             {