address Jason's feedback

Steve Lee (POWERSHELL) · Steve Lee (POWERSHELL) · commit dca5d00a2ad1 · 2018-12-24T17:57:58.000-08:00
diff --git a/src/System.Management.Automation/namespaces/FileSystemProvider.cs b/src/System.Management.Automation/namespaces/FileSystemProvider.cs
@@ -2434,10 +2434,14 @@ protected override void NewItem(
 
         private static bool WinCreateSymbolicLink(string path, string strTargetPath, bool isDirectory)
         {
-            int created = NativeMethods.CreateSymbolicLink(
-                path,
-                strTargetPath,
-                (isDirectory ? NativeMethods.SymbolicLinkFlags.Directory : NativeMethods.SymbolicLinkFlags.File) | NativeMethods.SymbolicLinkFlags.AllowUnprivilegedCreate);
+            // The new AllowUnprivilegedCreate is only available on Win10 build 14972 or newer
+            var flags = isDirectory ? NativeMethods.SymbolicLinkFlags.Directory : NativeMethods.SymbolicLinkFlags.File;
+            if (Environment.OSVersion.Version.Major >= 10 && Environment.OSVersion.Version.Build >= 14972)
+            {
+                flags |= NativeMethods.SymbolicLinkFlags.AllowUnprivilegedCreate;
+            }
+
+            int created = NativeMethods.CreateSymbolicLink(path, strTargetPath, flags);
             return (created == 1) ? true : false;
         }
 
diff --git a/test/powershell/Modules/Microsoft.PowerShell.Management/New-Item.Tests.ps1 b/test/powershell/Modules/Microsoft.PowerShell.Management/New-Item.Tests.ps1
@@ -269,13 +269,13 @@ Describe "New-Item with links fails for non elevated user if developer mode not
         Remove-Item -Path $testFilePath -Force -ErrorAction SilentlyContinue
     }
 
-    It "Should error correctly when failing to create a symbolic link and not in developer mode" -Skip:(!$IsWindows -or $developerMode) {
+    It "Should error correctly when failing to create a symbolic link and not in developer mode" -Skip:(!$IsWindows -or $developerMode -or (Test-IsElevated)) {
         { New-Item -ItemType SymbolicLink -Path $TestFilePath -Target $FullyQualifiedFile -ErrorAction Stop } |
         Should -Throw -ErrorId "NewItemSymbolicLinkElevationRequired,Microsoft.PowerShell.Commands.NewItemCommand"
         $TestFilePath | Should -Not -Exist
     }
 
-    It "Should succeed to create a symbolic link without elevation and in developer mode" -Skip:(!$IsWindows -or !$developerMode) {
+    It "Should succeed to create a symbolic link without elevation and in developer mode" -Skip:(!$IsWindows -or !$developerMode -or (Test-IsElevated)) {
         { New-Item -ItemType SymbolicLink -Path $TestFilePath -Target $FullyQualifiedFile -ErrorAction Stop } | Should -Not -Throw
         $TestFilePath | Should -Exist
     }

Original file line number	Diff line number	Diff line change
`@@ -269,13 +269,13 @@ Describe "New-Item with links fails for non elevated user if developer mode not`
`269`	`269`	`Remove-Item -Path $testFilePath -Force -ErrorAction SilentlyContinue`
`270`	`270`	`}`
`271`	`271`
`272`		`- It "Should error correctly when failing to create a symbolic link and not in developer mode" -Skip:(!$IsWindows -or $developerMode) {`
	`272`	`+ It "Should error correctly when failing to create a symbolic link and not in developer mode" -Skip:(!$IsWindows -or $developerMode -or (Test-IsElevated)) {`
`273`	`273`	`{ New-Item -ItemType SymbolicLink -Path $TestFilePath -Target $FullyQualifiedFile -ErrorAction Stop } \|`
`274`	`274`	`Should -Throw -ErrorId "NewItemSymbolicLinkElevationRequired,Microsoft.PowerShell.Commands.NewItemCommand"`
`275`	`275`	`$TestFilePath \| Should -Not -Exist`
`276`	`276`	`}`
`277`	`277`
`278`		`- It "Should succeed to create a symbolic link without elevation and in developer mode" -Skip:(!$IsWindows -or !$developerMode) {`
	`278`	`+ It "Should succeed to create a symbolic link without elevation and in developer mode" -Skip:(!$IsWindows -or !$developerMode -or (Test-IsElevated)) {`
`279`	`279`	`{ New-Item -ItemType SymbolicLink -Path $TestFilePath -Target $FullyQualifiedFile -ErrorAction Stop } \| Should -Not -Throw`
`280`	`280`	`$TestFilePath \| Should -Exist`
`281`	`281`	`}`