Refactor Get-SqlDscRSDatabaseInstallation to check result length and update related tests

Author: johlju

source/Public/Get-SqlDscRSDatabaseInstallation.ps1

@@ -77,15 +77,16 @@ function Get-SqlDscRSDatabaseInstallation
             $result = Invoke-RsCimMethod @invokeRsCimMethodParameters -ErrorAction 'Stop'
 
             <#
-                The WMI method returns multiple parallel arrays:
+                The WMI method returns:
+                - Length: Number of entries in the arrays
                 - InstallationID: Array of installation IDs
                 - MachineName: Array of machine names
                 - InstanceName: Array of instance names
                 - IsInitialized: Array of initialization states
             #>
-            if ($result.InstallationID)
+            if ($result.Length -gt 0)
             {
-                for ($i = 0; $i -lt $result.InstallationID.Count; $i++)
+                for ($i = 0; $i -lt $result.Length; $i++)
                 {
                     [PSCustomObject] @{
                         InstallationID = $result.InstallationID[$i]

tests/Unit/Public/Get-SqlDscRSDatabaseInstallation.Tests.ps1

@@ -71,10 +71,11 @@ Describe 'Get-SqlDscRSDatabaseInstallation' {
 
             Mock -CommandName Invoke-RsCimMethod -MockWith {
                 return @{
+                    Length         = 2
                     InstallationID = @('GUID1', 'GUID2')
-                    MachineName = @('SERVER1', 'SERVER2')
-                    InstanceName = @('SSRS', 'SSRS')
-                    IsInitialized = @($true, $true)
+                    MachineName    = @('SERVER1', 'SERVER2')
+                    InstanceName   = @('SSRS', 'SSRS')
+                    IsInitialized  = @($true, $true)
                 }
             }
         }
@@ -103,10 +104,11 @@ Describe 'Get-SqlDscRSDatabaseInstallation' {
 
             Mock -CommandName Invoke-RsCimMethod -MockWith {
                 return @{
+                    Length         = 0
                     InstallationID = @()
-                    MachineName = @()
-                    InstanceName = @()
-                    IsInitialized = @()
+                    MachineName    = @()
+                    InstanceName   = @()
+                    IsInitialized  = @()
                 }
             }
         }
@@ -144,10 +146,11 @@ Describe 'Get-SqlDscRSDatabaseInstallation' {
 
             Mock -CommandName Invoke-RsCimMethod -MockWith {
                 return @{
+                    Length         = 1
                     InstallationID = @('GUID1')
-                    MachineName = @('SERVER1')
-                    InstanceName = @('SSRS')
-                    IsInitialized = @($true)
+                    MachineName    = @('SERVER1')
+                    InstanceName   = @('SSRS')
+                    IsInitialized  = @($true)
                 }
             }
         }