Use absolute path in FileSystemProvider.CreateDirectory (#24615)

src/System.Management.Automation/namespaces/FileSystemProvider.cs

@@ -2665,12 +2665,6 @@ namespace Microsoft.PowerShell.Commands
                 !string.IsNullOrEmpty(path),
                 "The caller should verify path");
 
-            // Get the parent path
-            string parentPath = GetParentPath(path, null);
-
-            // The directory name
-            string childName = GetChildName(path);
-
             ErrorRecord error = null;
             if (!Force && ItemExists(path, out error))
             {
@@ -2700,7 +2694,7 @@ namespace Microsoft.PowerShell.Commands
 
                 if (ShouldProcess(resource, action))
                 {
-                    var result = Directory.CreateDirectory(Path.Combine(parentPath, childName));
+                    var result = Directory.CreateDirectory(path);
 
                     if (streamOutput)
                     {

test/powershell/Modules/Microsoft.PowerShell.Management/FileSystem.Tests.ps1

@@ -1206,6 +1206,20 @@ Describe "Extended FileSystem Item/Content Cmdlet Provider Tests" -Tags "Feature
             $result.Name | Should -BeExactly $testDir
         }
 
+        It "Verify Directory creation when path relative to current PSDrive is empty" {
+            try {
+                $rootDir = New-Item "NewDirectory" -ItemType Directory -Force
+                $rootPath = $rootDir.FullName
+                $newPSDrive = New-PSDrive -Name "NewPSDrive" -PSProvider FileSystem -Root $rootPath
+
+                $result = New-Item -Path "NewPSDrive:\" -ItemType Directory -Force
+                $result.FullName.TrimEnd("/\") | Should -BeExactly $newPSDrive.Root
+            }
+            finally {
+                Remove-PSDrive -Name "NewPSDrive" -Force -ErrorAction SilentlyContinue
+            }
+        }
+
         It "Verify File + Value" {
             $result = New-Item -Path . -ItemType File -Name $testFile -Value "Some String"
             $content = Get-Content -Path $testFile