🪲 [Fix]: Type-accelerator tests handle modules without enums or classes (#120)

Module test runs now handle modules that export only one kind of public
type under Pester 6. Type-accelerator checks skip empty enum or class
collections instead of failing discovery, so `Test-PSModule` can
validate modules that have classes without enums, enums without classes,
or both.

## Fixed: Type-accelerator tests handle missing enum or class exports

Modules no longer fail the `Test-PSModule` module test suite just
because one type category is empty. If a module has public classes but
no public enums, the enum registration check is skipped and the class
registration checks still run. If a module has public enums but no
public classes, the class registration check is skipped and the enum
registration checks still run.

This resolves the Pester 6 discovery failure caused by empty `-ForEach`
collections while preserving coverage for the exported types that do
exist.

## Technical Details

- `src/tests/Module/PSModule/PSModule.Tests.ps1` now passes
`-AllowNullOrEmptyForEach` to both type-accelerator `It` blocks.
- `.github/workflows/Action-Test-outputs.yml` now runs the output
fixture workflow against both the existing class-only fixture and a new
enum-only fixture.
- `tests/outputEnumOnlyTestRepo/outputs/module/PSModuleEnumOnly` adds a
minimal enum-only module fixture for the missing coverage path.
- The enum-only fixture cleanup only removes accelerators that still
point to the type exported by that fixture, avoiding removal of
pre-existing accelerators with the same name.

Author: MariusStorhaug

.github/workflows/Action-Test-outputs.yml

@@ -16,11 +16,18 @@ permissions: {}
 
 jobs:
   ActionTestOutputs:
-    name: Action-Test [outputs] - [${{ matrix.os }}]
+    name: Action-Test [outputs/${{ matrix.fixture.name }}] - [${{ matrix.os }}]
     strategy:
       fail-fast: false
       matrix:
         os: [ubuntu-latest, macos-latest, windows-latest]
+        fixture:
+          - name: PSModuleTest
+            workingDirectory: tests/outputTestRepo
+            coveragePercentTarget: 30
+          - name: PSModuleEnumOnly
+            workingDirectory: tests/outputEnumOnlyTestRepo
+            coveragePercentTarget: 0
     runs-on: ${{ matrix.os }}
     steps:
       - name: Checkout repo
@@ -32,7 +39,7 @@ jobs:
         uses: ./
         id: action-test
         with:
-          Name: PSModuleTest
-          WorkingDirectory: tests/outputTestRepo
+          Name: ${{ matrix.fixture.name }}
+          WorkingDirectory: ${{ matrix.fixture.workingDirectory }}
           Settings: Module
-          CodeCoverage_CoveragePercentTarget: 30
+          CodeCoverage_CoveragePercentTarget: ${{ matrix.fixture.coveragePercentTarget }}

src/tests/Module/PSModule/PSModule.Tests.ps1

@@ -93,12 +93,12 @@ Describe 'PSModule - Module tests' {
         BeforeAll {
             Import-Module -Name $moduleManifestPath -Force
         }
-        It 'Should register public enum [<_>] as a type accelerator' -ForEach $expectedEnumNames {
+        It 'Should register public enum [<_>] as a type accelerator' -ForEach $expectedEnumNames -AllowNullOrEmptyForEach {
             $registered = [psobject].Assembly.GetType('System.Management.Automation.TypeAccelerators')::Get
             $registered.Keys | Should -Contain $_ -Because 'the framework registers public enums as type accelerators'
         }
 
-        It 'Should register public class [<_>] as a type accelerator' -ForEach $expectedClassNames {
+        It 'Should register public class [<_>] as a type accelerator' -ForEach $expectedClassNames -AllowNullOrEmptyForEach {
             $registered = [psobject].Assembly.GetType('System.Management.Automation.TypeAccelerators')::Get
             $registered.Keys | Should -Contain $_ -Because 'the framework registers public classes as type accelerators'
         }

tests/outputEnumOnlyTestRepo/outputs/module/PSModuleEnumOnly/PSModuleEnumOnly.psd1

@@ -0,0 +1,36 @@
+@{
+    RootModule            = 'PSModuleEnumOnly.psm1'
+    ModuleVersion         = '999.0.0'
+    CompatiblePSEditions  = @(
+        'Core'
+        'Desktop'
+    )
+    GUID                  = 'b1c8c046-2253-4f30-8e08-e98a222a954a'
+    Author                = 'PSModule'
+    CompanyName           = 'PSModule'
+    Copyright             = '(c) 2024 PSModule. All rights reserved.'
+    Description           = 'Fixture module with enum type accelerators and no class type accelerators.'
+    PowerShellVersion     = '5.1'
+    ProcessorArchitecture = 'None'
+    FunctionsToExport     = @()
+    CmdletsToExport       = @()
+    VariablesToExport     = @()
+    AliasesToExport       = @()
+    FileList              = @(
+        'PSModuleEnumOnly.psd1'
+        'PSModuleEnumOnly.psm1'
+    )
+    PrivateData           = @{
+        PSData = @{
+            Tags       = @(
+                'workflow'
+                'powershell'
+                'powershell-module'
+                'PSEdition_Desktop'
+                'PSEdition_Core'
+            )
+            LicenseUri = 'https://github.com/PSModule/Test-PSModule/blob/main/LICENSE'
+            ProjectUri = 'https://github.com/PSModule/Test-PSModule'
+        }
+    }
+}

tests/outputEnumOnlyTestRepo/outputs/module/PSModuleEnumOnly/PSModuleEnumOnly.psm1

@@ -0,0 +1,48 @@
+[CmdletBinding()]
+param()
+
+enum ModuleLifecycle {
+    Loaded
+    Removed
+}
+
+#region Class exporter
+$TypeAcceleratorsClass = [psobject].Assembly.GetType(
+    'System.Management.Automation.TypeAccelerators'
+)
+$ExistingTypeAccelerators = $TypeAcceleratorsClass::Get
+$ExportableEnums = @(
+    [ModuleLifecycle]
+)
+$ExportableEnums | ForEach-Object { Write-Verbose "Exporting enum '$($_.FullName)'." }
+foreach ($Type in $ExportableEnums) {
+    if ($Type.FullName -in $ExistingTypeAccelerators.Keys) {
+        Write-Verbose "Enum already exists [$($Type.FullName)]. Skipping."
+    } else {
+        Write-Verbose "Importing enum '$Type'."
+        $TypeAcceleratorsClass::Add($Type.FullName, $Type)
+    }
+}
+$ExportableClasses = @(
+)
+$ExportableClasses | ForEach-Object { Write-Verbose "Exporting class '$($_.FullName)'." }
+foreach ($Type in $ExportableClasses) {
+    if ($Type.FullName -in $ExistingTypeAccelerators.Keys) {
+        Write-Verbose "Class already exists [$($Type.FullName)]. Skipping."
+    } else {
+        Write-Verbose "Importing class '$Type'."
+        $TypeAcceleratorsClass::Add($Type.FullName, $Type)
+    }
+}
+
+$MyInvocation.MyCommand.ScriptBlock.Module.OnRemove = {
+    $CurrentTypeAccelerators = $TypeAcceleratorsClass::Get
+    foreach ($Type in ($ExportableEnums + $ExportableClasses)) {
+        if ($CurrentTypeAccelerators[$Type.FullName] -eq $Type) {
+            $null = $TypeAcceleratorsClass::Remove($Type.FullName)
+        }
+    }
+}.GetNewClosure()
+#endregion Class exporter
+
+Export-ModuleMember -Function @() -Alias @() -Variable @()

tests/outputEnumOnlyTestRepo/tests/.gitkeep

@@ -0,0 +1 @@
+Tracks the fixture tests directory required by the action setup step.