ModuleManifest.Tests.ps1

<#
 Assumptions:
 -- uses v3 module manifest (RootModule rather than ModuleToProcess)
 -- RootModule contains name of the file only
 -- Certain pattern can be used to check only functions that follow naming convention (here: *-Cim*)
 Also:
 -- Actual tests include more actions related to manifest contents, thus "context" block is used
 -- Actual test is testing multiple modules/ manifests, thus $manifest in the real scenario is part of foreach ($manifest in ls) {}
#>

$manifest = Get-Item -Path $env:ProgramFiles\WindowsPowerShell\Modules\CimInventory\*\CimInventory.psd1
Describe "Testing Module Manifest Metadata: $($manifest.BaseName)" {
    It 'Has proper manifest' {
        { Test-ModuleManifest -Path $manifest.FullName } | Should not throw
    }
    Context "Testing properties within module manifest $($manifest.BaseName)" {
        $moduleInfo = Test-ModuleManifest -Path $manifest.FullName -ErrorAction SilentlyContinue    
        if ($moduleInfo.RootModule) {
            $fullPath = $manifest.FullName | Split-Path -Parent | Join-Path -ChildPath $moduleInfo.RootModule

            $ast = [System.Management.Automation.Language.Parser]::ParseFile($fullPath, [ref]$null, [ref]$null)
            $functionNames = $ast.FindAll(
                { 
                    $args[0] -is [System.Management.Automation.Language.FunctionDefinitionAst] -and
                    $args[0].Name -like '*-Cim*'
                },
                $false

            ) | ForEach-Object Name
            $exportedFunctions = $moduleInfo.ExportedFunctions.Keys

            foreach ($name in $functionNames) {

                It "$($moduleInfo.Name) exports function $name in manifest" {
                    
                    # We aim for explicit list of functions, but for some modules we are using simple *-Prefix*

                    if ([System.Management.Automation.WildcardPattern]::ContainsWildcardCharacters($exportedFunctions)) {
                        $name -like $exportedFunctions | Should be $true
                    } else {
                        $exportedFunctions -contains $name | Should be $true
                    }
                }
            }    
        }
    }
}