Add comprehensive test examples demonstrating test coverage checklist

[Copilot]

The test coverage checklist in CONTRIBUTING.md listed comprehensive testing scenarios (invalid inputs, edge cases, permissions, dependencies) but the reference PowerShell test file only contained basic validation and a smoke test.

Changes

Test Suite Enhancement (tests/unit/PowerShell/system-maintenance.Tests.ps1)

• Expanded from 4 to 22 tests demonstrating each checklist scenario:
  • Invalid inputs: out-of-range values, negative values, type mismatches
  • Edge cases: zero, boundary values (0, 1, 3650), extremes
  • Permissions: admin requirement verification
  • Dependencies: optional module handling
  • WhatIf support: comprehensive destructive operation preview
  • Error handling: StrictMode, ErrorActionPreference, try-catch verification
  • Logging: path resolution and fallback behavior

Documentation (CONTRIBUTING.md)

• Added reference to enhanced test file as implementation example

CI/Configuration Fixes

• Added SCRIPTS_ROOT environment variable to CI workflow for test path resolution
• Fixed PSScriptAnalyzer duplicate parameter in .pre-commit-config.yaml

Example

Context "Invalid Inputs" {
    It "should reject MaxTempFileAgeDays below minimum (negative values)" {
        { & $localPath -MaxTempFileAgeDays -1 -WhatIf } | Should -Throw
    }
    
    It "should reject MaxTempFileAgeDays above maximum (> 3650)" {
        { & $localPath -MaxTempFileAgeDays 9999 -WhatIf } | Should -Throw
    }
}

Context "Edge Cases" {
    It "should handle MaxTempFileAgeDays = 0 (delete all temp files)" {
        { & $localPath -MaxTempFileAgeDays 0 -WhatIf } | Should -Not -Throw
    }
}

All 22 tests pass. The test file now serves as a working reference implementation of the checklist.

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[Copilot]

Pull Request Overview

This PR significantly enhances the PowerShell test suite by adding comprehensive test coverage examples that demonstrate the testing checklist scenarios outlined in CONTRIBUTING.md. The test file expands from 4 to 22 tests, serving as a reference implementation for contributors.

Key Changes:

• Expanded test coverage to demonstrate invalid input handling, edge cases, permissions checks, dependency handling, WhatIf support, and error handling patterns
• Added SCRIPTS_ROOT environment variable to CI workflow for proper test path resolution
• Removed unnecessary path exclusions from PSScriptAnalyzer pre-commit configuration
• Updated CONTRIBUTING.md to reference the enhanced test file as an example

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

File	Description
tests/unit/PowerShell/system-maintenance.Tests.ps1	Added 18 new tests demonstrating comprehensive coverage of invalid inputs, edge cases, permissions, dependencies, WhatIf support, parameter validation, logging, and error handling scenarios
CONTRIBUTING.md	Added reference to the enhanced test file as a practical example of the test coverage checklist
.github/workflows/ci.yml	Added SCRIPTS_ROOT environment variable to support test path resolution in CI
.pre-commit-config.yaml	Removed unnecessary -Exclude parameter for non-existent testing/ and templates/ directories

[Copilot]

This test is fragile because it relies on counting string splits of 'try\s*{' patterns. The magic number "5" is unexplained and could easily break with script refactoring that doesn't meaningfully change error handling behavior. For example, adding or removing a single try-catch block would fail this test even if error handling remains adequate.

Consider either:

1. Removing this test entirely since the presence of try-catch blocks doesn't guarantee proper error handling
2. Testing actual error handling behavior by invoking the script in error scenarios
3. If testing for try-catch presence is important, document why "5" is the threshold and what it represents

Suggested change

	It "should include try-catch blocks for error handling" {
	$content = Get-Content -Path $scriptPath -Raw
	# Check that the script uses try-catch for error handling
	($content -split 'try\s*\{').Count | Should -BeGreaterThan 5
	}