Only for Windows because env variables is very different on Unix + Ma…

…ke path to returning standard paths shorter

src/code/SetPSResourceGetInstallPathOverride.cs

@@ -4,6 +4,7 @@
 using Microsoft.PowerShell.PSResourceGet.UtilClasses;
 using System;
 using System.Management.Automation;
+using System.Runtime.InteropServices;
 
 namespace Microsoft.PowerShell.PSResourceGet.Cmdlets
 {
@@ -36,13 +37,25 @@ public sealed class SetPSResourceGetInstallPathOverride : PSCmdlet
 
         protected override void BeginProcessing()
         {
+            // Only run on Windows for now, due to env variables on Unix being very different
+            if (RuntimeInformation.IsOSPlatform(OSPlatform.Windows)) {
+                ThrowTerminatingError(
+                    new ErrorRecord(
+                        new PSInvalidOperationException($"Error this only works on Windows for now'"),
+                        "PathMissingExpectedSubdirectories",
+                        ErrorCategory.InvalidOperation,
+                        this
+                    )
+                );
+            }
+
             // Validate path is not null or empty
             if (string.IsNullOrEmpty(Path)) {
                 ThrowTerminatingError(
                     new ErrorRecord(
                         new PSInvalidOperationException($"Error input path is null or empty: '{Path}'"),
                         "PathMissingExpectedSubdirectories",
-                        ErrorCategory.InvalidOperation,
+                        ErrorCategory.InvalidArgument,
                         this
                     )
                 );
@@ -54,7 +67,7 @@ protected override void BeginProcessing()
                     new ErrorRecord(
                         new PSInvalidOperationException($"Error input path is not rooted / absolute: '{Path}'"),
                         "PathMissingExpectedSubdirectories",
-                        ErrorCategory.InvalidOperation,
+                        ErrorCategory.InvalidArgument,
                         this
                     )
                 );

src/code/Utils.cs

@@ -990,60 +990,84 @@ public static string GetInstalledPackageName(string pkgPath)
             return new DirectoryInfo(pkgPath).Parent.Name;
         }
 
-        // Find all potential resource paths
-        public static List<string> GetPathsFromEnvVarAndScope(
+        // Get standard install paths given scope
+        public static List<string> GetStandardPathsForScope(
             PSCmdlet psCmdlet,
             ScopeType? scope)
         {
             // Assets
             List<string> resourcePaths = new();
 
+            // Get standard paths
+            GetStandardPlatformPaths(
+                psCmdlet,
+                out string myDocumentsPath,
+                out string programFilesPath
+            );
+
+            // Add paths to output
+            if (scope.Value is ScopeType.AllUsers)
+            {
+                resourcePaths.Add(Path.Combine(programFilesPath, "Modules"));
+                resourcePaths.Add(Path.Combine(programFilesPath, "Scripts"));
+            }
+            else
+            {
+                resourcePaths.Add(Path.Combine(myDocumentsPath, "Modules"));
+                resourcePaths.Add(Path.Combine(myDocumentsPath, "Scripts"));
+            }
+
+            // Return results
+            return resourcePaths;
+        }
+
+        // Find all potential resource paths
+        public static List<string> GetPathsFromEnvVarAndScope(
+            PSCmdlet psCmdlet,
+            ScopeType? scope)
+        {
+            // Path override is only implemented for Windows so far
+            if (!RuntimeInformation.IsOSPlatform(OSPlatform.Windows)) {
+                return GetStandardPathsForScope(psCmdlet,scope);
+            }
+
             // Get value of path override environment variable
             string pathOverride = Environment.GetEnvironmentVariable(
                 "PSResourceGetInstallPathOverride",
                 (scope.Value is ScopeType.AllUsers) ? EnvironmentVariableTarget.Machine : EnvironmentVariableTarget.User
             );
 
-            // Try to expand path override
-            if (!string.IsNullOrEmpty(pathOverride)) {
+            // Return standard paths if no override was found, else try to expand paths found in override
+            if (string.IsNullOrEmpty(pathOverride)) {
+                return GetStandardPathsForScope(psCmdlet,scope);
+            }
+            else {
                 try
                 {
                     pathOverride = Environment.ExpandEnvironmentVariables(pathOverride);
                 }
                 catch (ArgumentException)
                 {
-                    pathOverride = string.Empty;
-                    psCmdlet.WriteVerbose("Path override was found, but could not expand environment variable(s).");
+                    psCmdlet.WriteWarning("Path override was found, but could not expand environment variable(s). Falling back to standard paths.");
+                    return GetStandardPathsForScope(psCmdlet,scope);
                 }
             }
 
             // Return override if present, else use default paths
             if (!string.IsNullOrEmpty(pathOverride) && Path.IsPathRooted(pathOverride) && Directory.Exists(pathOverride))
             {
-                psCmdlet.WriteVerbose(string.Format("Path override was found, using '{0}' as base.",pathOverride));
-                resourcePaths.Add(Path.Combine(pathOverride, "Modules"));
-                resourcePaths.Add(Path.Combine(pathOverride, "Scripts"));
+                psCmdlet.WriteVerbose(string.Format("Path override was found, using '{0}' as base.", pathOverride));
+                // Assets
+                List<string> resourcePaths = new()
+                {
+                    Path.Combine(pathOverride, "Modules"),
+                    Path.Combine(pathOverride, "Scripts")
+                };
+                return resourcePaths;
             }
             else {
-                GetStandardPlatformPaths(
-                    psCmdlet,
-                    out string myDocumentsPath,
-                    out string programFilesPath
-                );
-                if (scope.Value is ScopeType.AllUsers)
-                {
-                    resourcePaths.Add(Path.Combine(programFilesPath, "Modules"));
-                    resourcePaths.Add(Path.Combine(programFilesPath, "Scripts"));
-                }
-                else
-                {
-                    resourcePaths.Add(Path.Combine(myDocumentsPath, "Modules"));
-                    resourcePaths.Add(Path.Combine(myDocumentsPath, "Scripts"));
-                }
+                return GetStandardPathsForScope(psCmdlet,scope);
             }
-
-            // Return results
-            return resourcePaths;
         }
 
         public static List<string> GetAllResourcePaths(