Add Pester Tests for YamlCreate.InstallerDetection (#327538)

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: Trenly <12611259+Trenly@users.noreply.github.com>

Author: Trenly

.github/workflows/pesterTests.yaml

@@ -0,0 +1,51 @@
+name: Pester Tests
+
+on:
+  pull_request:
+    branches:
+      - master
+    paths:
+      - "**/*.ps1"
+      - "**/*.psm1"
+      - "**/*.psd1"
+  push:
+    paths:
+      - "**/*.ps1"
+      - "**/*.psm1"
+      - "**/*.psd1"
+
+permissions:
+  contents: read # Needed to check out the code
+  pull-requests: read # Needed to read pull request details
+
+jobs:
+  test:
+    runs-on: windows-latest
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v3
+      - name: Install Pester
+        run: |
+          # Pester 5.x is already included in Windows runners, but ensure latest version
+          Install-Module -Name Pester -Force -SkipPublisherCheck -Scope CurrentUser -MinimumVersion 5.0.0
+      - name: Run Pester Tests
+        run: |
+          # Find and run all Pester test files
+          $testFiles = Get-ChildItem -Recurse -Filter *.Tests.ps1
+          if ($testFiles) {
+            Write-Host "Found $($testFiles.Count) test file(s)"
+            foreach ($testFile in $testFiles) {
+              Write-Host "Running tests in: $($testFile.FullName)"
+            }
+
+            # Run all tests
+            $config = New-PesterConfiguration
+            $config.Run.Path = $testFiles.FullName
+            $config.Run.Exit = $true
+            $config.Output.Verbosity = 'Detailed'
+            $config.TestResult.Enabled = $true
+
+            Invoke-Pester -Configuration $config
+          } else {
+            Write-Host "No Pester test files found."
+          }

.github/workflows/scriptAnalyzer.yaml

@@ -7,10 +7,12 @@ on:
     paths:
       - "**/*.ps1"
       - "**/*.psm1"
+      - "**/*.psd1"
   push:
     paths:
       - "**/*.ps1"
       - "**/*.psm1"
+      - "**/*.psd1"
 
 permissions:
   contents: read # Needed to check out the code

Tools/Modules/YamlCreate/YamlCreate.InstallerDetection/README.md

@@ -0,0 +1,94 @@
+# YamlCreate.InstallerDetection Tests
+
+This directory contains Pester tests for the YamlCreate.InstallerDetection PowerShell module.
+
+## Overview
+
+The test suite validates the functionality of the installer detection module, which provides functions to:
+- Parse PE file structures
+- Detect various installer types (ZIP, MSIX, MSI, WIX, Nullsoft, Inno, Burn)
+- Identify font files
+- Resolve installer types from file paths
+
+## Running the Tests
+
+### Prerequisites
+
+- PowerShell 7.0 or later
+- Pester 5.x (included with PowerShell 7+)
+
+### Run All Tests
+
+From the module directory, run:
+
+```powershell
+Invoke-Pester -Path ./YamlCreate.InstallerDetection.Tests.ps1
+```
+
+### Run Tests with Detailed Output
+
+For more detailed test output:
+
+```powershell
+Invoke-Pester -Path ./YamlCreate.InstallerDetection.Tests.ps1 -Output Detailed
+```
+
+### Run Tests with Code Coverage
+
+To see code coverage metrics:
+
+```powershell
+Invoke-Pester -Path ./YamlCreate.InstallerDetection.Tests.ps1 -CodeCoverage ./YamlCreate.InstallerDetection.psm1
+```
+
+## Test Structure
+
+The test suite is organized into the following sections:
+
+### Module Tests
+- Module import validation
+- Exported functions verification
+
+### Function Tests
+- **Get-OffsetBytes**: Tests for byte array extraction with various offsets and endianness
+- **Get-PESectionTable**: Tests for PE file parsing
+- **Test-IsZip**: Tests for ZIP file detection
+- **Test-IsMsix**: Tests for MSIX/APPX detection
+- **Test-IsMsi**: Tests for MSI installer detection
+- **Test-IsWix**: Tests for WIX installer detection
+- **Test-IsNullsoft**: Tests for Nullsoft installer detection
+- **Test-IsInno**: Tests for Inno Setup installer detection
+- **Test-IsBurn**: Tests for Burn installer detection
+- **Test-IsFont**: Tests for font file detection (TTF, OTF, TTC)
+- **Resolve-InstallerType**: Tests for the main installer type resolution function
+
+## Known Limitations
+
+Some tests are skipped due to complexity or external dependencies:
+
+1. **ZIP Archive Tests**: Tests that require complete valid ZIP archives are skipped as they would need complex ZIP structure generation
+2. **PE File Tests**: Some PE-related tests are skipped when they would require reading non-existent files
+3. **External Dependencies**: The module relies on external commands (`Get-MSITable`, `Get-MSIProperty`, `Get-Win32ModuleResource`) that are stubbed in the test environment
+
+## Test Coverage
+
+Current test coverage includes:
+- 32 passing tests
+- 3 skipped tests (require complex setup)
+- Covers all 11 exported functions
+- Tests both positive and negative scenarios
+- Validates edge cases and error handling
+
+## Contributing
+
+When adding new functions to the module:
+1. Add corresponding tests to `YamlCreate.InstallerDetection.Tests.ps1`
+2. Follow the existing test structure (Describe → Context → It blocks)
+3. Use descriptive test names that explain what is being tested
+4. Include both positive and negative test cases
+5. Clean up any temporary files created during tests
+
+## Additional Resources
+
+- [Pester Documentation](https://pester.dev/)
+- [PowerShell Testing Best Practices](https://pester.dev/docs/usage/test-file-structure)