Refactor test scripts to use consistent module name variable (#2385)

Author: johlju

.github/instructions/dsc-community-style-guidelines-integration-tests.instructions.md

@@ -47,6 +47,6 @@ BeforeDiscovery {
 BeforeAll {
     $script:moduleName = '{MyModuleName}'
 
-    Import-Module -Name $script:moduleName -Force -ErrorAction 'Stop'
+    Import-Module -Name $script:moduleName -ErrorAction 'Stop'
 }
 ```

.github/instructions/dsc-community-style-guidelines-unit-tests.instructions.md

@@ -43,7 +43,7 @@ BeforeDiscovery {
 BeforeAll {
     $script:moduleName = '{MyModuleName}'
 
-    Import-Module -Name $script:moduleName -Force -ErrorAction 'Stop'
+    Import-Module -Name $script:moduleName -ErrorAction 'Stop'
 
     $PSDefaultParameterValues['InModuleScope:ModuleName'] = $script:moduleName
     $PSDefaultParameterValues['Mock:ModuleName'] = $script:moduleName
@@ -54,9 +54,6 @@ AfterAll {
     $PSDefaultParameterValues.Remove('InModuleScope:ModuleName')
     $PSDefaultParameterValues.Remove('Mock:ModuleName')
     $PSDefaultParameterValues.Remove('Should:ModuleName')
-
-    # Unload the module being tested so that it doesn't impact any other tests.
-    Get-Module -Name $script:moduleName -All | Remove-Module -Force
 }
 ```
 

CHANGELOG.md

@@ -104,6 +104,15 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Fixed
 
+- Unit Tests
+  - Fixed PowerShell class type identity issues that caused "Cannot convert
+    'Type' to 'Type'" errors when running multiple test files in the same
+    Pester job. The issue occurred because using `Import-Module -Force` and
+    `Remove-Module` between test files caused PowerShell to create new type
+    identities for module-defined classes. Changed all unit test files to not
+    use `-Force` when importing the module being tested and removed the module
+    unload from `AfterAll` blocks. This prevents class type identity mismatches
+    while maintaining test isolation through mock cleanup.
 - Fixed all `Invoke-WebRequest` calls throughout the codebase to include the
   `-UseBasicParsing` parameter. This addresses a Windows PowerShell 5.1 security
   update (CVE-2025-54100) released December 9, 2025, which changed the default

tests/Integration/Commands/Add-SqlDscFileGroup.Integration.Tests.ps1

@@ -26,7 +26,9 @@ BeforeDiscovery {
 BeforeAll {
     $script:moduleName = 'SqlServerDsc'
 
-    Import-Module -Name $script:moduleName -Force -ErrorAction 'Stop'
+    # Do not use -Force. Doing so, or unloading the module in AfterAll, causes
+    # PowerShell class types to get new identities, breaking type comparisons.
+    Import-Module -Name $script:moduleName -ErrorAction 'Stop'
 }
 
 Describe 'Add-SqlDscFileGroup' -Tag @('Integration_SQL2017', 'Integration_SQL2019', 'Integration_SQL2022') {

tests/Integration/Commands/Add-SqlDscTraceFlag.Integration.Tests.ps1

@@ -26,7 +26,9 @@ BeforeDiscovery {
 BeforeAll {
     $script:moduleName = 'SqlServerDsc'
 
-    Import-Module -Name $script:moduleName -Force -ErrorAction 'Stop'
+    # Do not use -Force. Doing so, or unloading the module in AfterAll, causes
+    # PowerShell class types to get new identities, breaking type comparisons.
+    Import-Module -Name $script:moduleName -ErrorAction 'Stop'
 }
 
 Describe 'Add-SqlDscTraceFlag' -Tag @('Integration_SQL2017', 'Integration_SQL2019', 'Integration_SQL2022') {

tests/Integration/Commands/Assert-SqlDscAgentOperator.Integration.Tests.ps1

@@ -26,7 +26,9 @@ BeforeDiscovery {
 BeforeAll {
     $script:moduleName = 'SqlServerDsc'
 
-    Import-Module -Name $script:moduleName -Force -ErrorAction 'Stop'
+    # Do not use -Force. Doing so, or unloading the module in AfterAll, causes
+    # PowerShell class types to get new identities, breaking type comparisons.
+    Import-Module -Name $script:moduleName -ErrorAction 'Stop'
 
     $env:SqlServerDscCI = $true
 
@@ -36,9 +38,6 @@ BeforeAll {
 
 AfterAll {
     $null = Remove-Item -Path 'Env:\SqlServerDscCI' -ErrorAction 'Stop'
-
-    # Unload the module being tested so that it doesn't impact any other tests.
-    Get-Module -Name $script:moduleName -All | Remove-Module -Force
 }
 
 Describe 'Assert-SqlDscAgentOperator' -Tag 'Integration_SQL2017', 'Integration_SQL2019', 'Integration_SQL2022' {

tests/Integration/Commands/Assert-SqlDscLogin.Integration.Tests.ps1

@@ -26,7 +26,9 @@ BeforeDiscovery {
 BeforeAll {
     $script:moduleName = 'SqlServerDsc'
 
-    Import-Module -Name $script:moduleName -Force -ErrorAction 'Stop'
+    # Do not use -Force. Doing so, or unloading the module in AfterAll, causes
+    # PowerShell class types to get new identities, breaking type comparisons.
+    Import-Module -Name $script:moduleName -ErrorAction 'Stop'
 }
 
 Describe 'Assert-SqlDscLogin' -Tag @('Integration_SQL2017', 'Integration_SQL2019', 'Integration_SQL2022') {

tests/Integration/Commands/Backup-SqlDscDatabase.Integration.Tests.ps1

@@ -26,7 +26,9 @@ BeforeDiscovery {
 BeforeAll {
     $script:moduleName = 'SqlServerDsc'
 
-    Import-Module -Name $script:moduleName -Force -ErrorAction 'Stop'
+    # Do not use -Force. Doing so, or unloading the module in AfterAll, causes
+    # PowerShell class types to get new identities, breaking type comparisons.
+    Import-Module -Name $script:moduleName -ErrorAction 'Stop'
 }
 
 Describe 'Backup-SqlDscDatabase' -Tag @('Integration_SQL2017', 'Integration_SQL2019', 'Integration_SQL2022') {

tests/Integration/Commands/Complete-SqlDscImage.Integration.Tests.ps1

@@ -27,7 +27,9 @@ BeforeDiscovery {
 BeforeAll {
     $script:moduleName = 'SqlServerDsc'
 
-    Import-Module -Name $script:moduleName -Force -ErrorAction 'Stop'
+    # Do not use -Force. Doing so, or unloading the module in AfterAll, causes
+    # PowerShell class types to get new identities, breaking type comparisons.
+    Import-Module -Name $script:moduleName -ErrorAction 'Stop'
 }
 
 # cSpell: ignore DSCSQLTEST, PrepareImage, CompleteImage

tests/Integration/Commands/Connect-SqlDscDatabaseEngine.Integration.Tests.ps1

@@ -26,7 +26,9 @@ BeforeDiscovery {
 BeforeAll {
     $script:moduleName = 'SqlServerDsc'
 
-    Import-Module -Name $script:moduleName -Force -ErrorAction 'Stop'
+    # Do not use -Force. Doing so, or unloading the module in AfterAll, causes
+    # PowerShell class types to get new identities, breaking type comparisons.
+    Import-Module -Name $script:moduleName -ErrorAction 'Stop'
 }
 
 # cSpell: ignore DSCSQLTEST