Fix Get-DomainName - retrieve computer NETBIOS domain name instead of user (#444)

Author: Borgquite

CHANGELOG.md

@@ -7,6 +7,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Fixed
 
+- Computer
+  - Fix Get-ComputerDomain function to retrieve the computer NETBIOS domain name instead of the user.
 - `UserAccountControl`
   - Tests remove parameter type on `Assert-BoundParameter` mocks.
 

source/DSCResources/DSC_Computer/DSC_Computer.psm1

@@ -630,7 +630,7 @@ function Get-ComputerDomain
         {
             if ($NetBios)
             {
-                $domainName = (Get-Item -Path Env:\USERDOMAIN).Value
+                $domainName = (Get-CimInstance -ClassName Win32_NTDomain -Filter "DnsForestName='$($domainInfo.Domain)'").DomainName
             }
             else
             {

tests/Unit/DSC_Computer.Tests.ps1

@@ -1707,17 +1707,17 @@ Describe 'DSC_Computer\Get-ComputerDomain' -Tag 'Private' {
                 }
             }
 
-            Mock -CommandName Get-Item -ParameterFilter { $Path -eq 'Env:\USERDOMAIN' } -MockWith {
+            Mock -CommandName Get-CimInstance -ParameterFilter { $ClassName -eq 'Win32_NTDomain' } -MockWith {
                 [PSCustomObject] @{
-                    Value = 'CONTOSO'
+                    DomainName = 'CONTOSO'
                 }
             }
         }
 
         BeforeDiscovery {
             $testCases = @(
-                @{ value = $true; result = 'CONTOSO'; GetItemCount = 1 }
-                @{ value = $false; result = 'contoso.com'; GetItemCount = 0 }
+                @{ value = $true; result = 'CONTOSO'; GetCimInstanceCount = 2 }
+                @{ value = $false; result = 'contoso.com'; GetCimInstanceCount = 1 }
             )
         }
 
@@ -1733,8 +1733,7 @@ Describe 'DSC_Computer\Get-ComputerDomain' -Tag 'Private' {
                     Get-ComputerDomain @getComputerDomainParameters | Should -Be $result
                 }
 
-                Should -Invoke -CommandName Get-CimInstance -Exactly -Times 1 -Scope It
-                Should -Invoke -CommandName Get-Item -Exactly -Times $GetItemCount -Scope It
+                Should -Invoke -CommandName Get-CimInstance -Exactly -Times $GetCimInstanceCount -Scope It
             }
         }
 
@@ -1747,9 +1746,9 @@ Describe 'DSC_Computer\Get-ComputerDomain' -Tag 'Private' {
                     }
                 }
 
-                Mock -CommandName Get-Item -ParameterFilter { $Path -eq 'Env:\USERDOMAIN' } -MockWith {
+                Mock -CommandName Get-CimInstance -ParameterFilter { $ClassName -eq 'Win32_NTDomain' } -MockWith {
                     [PSCustomObject] @{
-                        Value = 'CONTOSO'
+                        DomainName = 'CONTOSO'
                     }
                 }
             }
@@ -1761,7 +1760,6 @@ Describe 'DSC_Computer\Get-ComputerDomain' -Tag 'Private' {
                 }
 
                 Should -Invoke -CommandName Get-CimInstance -Exactly -Times 1 -Scope It
-                Should -Invoke -CommandName Get-Item -Exactly -Times 0 -Scope It
             }
         }
 
@@ -1782,9 +1780,9 @@ Describe 'DSC_Computer\Get-ComputerDomain' -Tag 'Private' {
                         }
                     }
 
-                    Mock -CommandName Get-Item -ParameterFilter { $Path -eq 'Env:\USERDOMAIN' } -MockWith {
+                    Mock -CommandName Get-CimInstance -ParameterFilter { $ClassName -eq 'Win32_NTDomain' } -MockWith {
                         [PSCustomObject] @{
-                            Value = 'Computer1'
+                            DomainName = $null
                         }
                     }
                 }
@@ -1801,7 +1799,6 @@ Describe 'DSC_Computer\Get-ComputerDomain' -Tag 'Private' {
                     }
 
                     Should -Invoke -CommandName Get-CimInstance -Exactly -Times 1 -Scope It
-                    Should -Invoke -CommandName Get-Item -Exactly -Times 0 -Scope It
                 }
             }
         }