Tests/QA/ExampleFiles.common.v5.Tests.ps1

<#
    .NOTES
        To run manually:
 
        $pathToHQRMTests = Join-Path -Path (Get-Module DscResource.Test).ModuleBase -ChildPath 'Tests\QA'
 
        $container = New-PesterContainer -Path "$pathToHQRMTests/ExampleFiles.common.*.Tests.ps1" -Data @{
            SourcePath = './source'
            # ExcludeSourceFile = @('MyExample.ps1')
        }
 
        Invoke-Pester -Container $container -Output Detailed
#>

param
(
    [Parameter()]
    [System.String]
    $SourcePath,

    [Parameter()]
    [System.String[]]
    $ExcludeSourceFile,

    [Parameter(ValueFromRemainingArguments = $true)]
    $Args
)

# This test _must_ be outside the BeforeDiscovery-block since Pester 4 does not recognizes it.
$isPester5 = (Get-Module -Name Pester).Version -ge '5.1.0'

# Only run if Pester 5.1.
if (-not $isPester5)
{
    Write-Verbose -Message 'Repository is using old Pester version, new HQRM tests for Pester 5 are skipped.' -Verbose
    return
}

BeforeDiscovery {
    # Re-imports the private (and public) functions.
    Import-Module -Name (Join-Path -Path $PSScriptRoot -ChildPath '../../DscResource.Test.psm1') -Force

    if (-not $SourcePath)
    {
        return
    }

    $examplesPath = Join-Path -Path $SourcePath -ChildPath 'Examples'

    # If there are no Examples folder, exit.
    if (-not (Test-Path -Path $examplesPath))
    {
        return
    }

    $exampleFiles = @(Get-ChildItem -Path $examplesPath -Filter '*.ps1' -Recurse | WhereSourceFileNotExcluded -ExcludeSourceFile $ExcludeSourceFile)

    $exampleToTest = @()

    foreach ($exampleFile in $exampleFiles)
    {
        $exampleToTest += @{
            ExampleFile            = $exampleFile
            ExampleDescriptiveName = Join-Path -Path (Split-Path $exampleFile.Directory -Leaf) -ChildPath (Split-Path $exampleFile -Leaf)
        }
    }
}

BeforeAll {
    # Re-imports the private (and public) functions.
    Import-Module -Name (Join-Path -Path $PSScriptRoot -ChildPath '../../DscResource.Test.psm1') -Force
}

AfterAll {
    # Re-import just the public functions.
    Import-Module -Name 'DscResource.Test' -Force
}

Describe 'Common Tests - Validate Example Files' -Tag 'Common Tests - Validate Example Files' {
    Context 'When the example ''<ExampleDescriptiveName>'' exist' -ForEach $exampleToTest {
        It 'Should compile the MOF schema for the example correctly' {
            {
                $mockPassword = ConvertTo-SecureString '&iPm%M5q3K$Hhq=wcEK' -AsPlainText -Force
                $mockCredential = New-Object -TypeName System.Management.Automation.PSCredential -ArgumentList @('username', $mockPassword)

                $mockConfigurationData = @{
                    AllNodes = @(
                        @{
                            NodeName                    = 'localhost'
                            PsDscAllowPlainTextPassword = $true
                        }
                    )
                }

                <#
                    Set this first because it is used in the final block,
                    and must be set otherwise it fails on not being assigned.
                #>

                $existingCommandName = $null

                try
                {
                    . $ExampleFile.FullName

                    <#
                        Test for either a configuration named 'Example',
                        or parse the name from the filename and try that
                        as the configuration name (requirement for Azure
                        Automation).
                    #>

                    $commandName = @(
                        'Example',
                        (Get-PublishFileName -Path $ExampleFile.FullName)
                    )

                    # Get the first one that matches.
                    $existingCommand = Get-ChildItem -Path 'function:' |
                        Where-Object { $_.Name -in $commandName } |
                        Select-Object -First 1

                    if ($existingCommand)
                    {
                        $existingCommandName = $existingCommand.Name

                        $exampleCommand = Get-Command -Name $existingCommandName -ErrorAction 'SilentlyContinue'

                        if ($exampleCommand)
                        {
                            $exampleParameters = @{}

                            # Remove any common parameters that are available.
                            $commandParameters = $exampleCommand.Parameters.Keys |
                                Where-Object -FilterScript {
                                    ($_ -notin [System.Management.Automation.PSCmdlet]::CommonParameters) -and `
                                    ($_ -notin [System.Management.Automation.PSCmdlet]::OptionalCommonParameters)
                                }

                            foreach ($parameterName in $commandParameters)
                            {
                                $parameterType = $exampleCommand.Parameters[$parameterName].ParameterType.FullName

                                <#
                                    Each credential parameter in the Example function is assigned the
                                    mocked credential. 'PsDscRunAsCredential' is not assigned because
                                    that breaks the example.
                                #>

                                if ($parameterName -ne 'PsDscRunAsCredential' `
                                        -and $parameterType -eq 'System.Management.Automation.PSCredential')
                                {
                                    $exampleParameters.Add($parameterName, $mockCredential)
                                }
                                else
                                {
                                    <#
                                        Check for mandatory parameters.
                                        Assume the parameters are all in the 'all' parameter set.
                                    #>

                                    $isParameterMandatory = $exampleCommand.Parameters[$parameterName].ParameterSets['__AllParameterSets'].IsMandatory
                                    if ($isParameterMandatory)
                                    {
                                        <#
                                            Convert '1' to the type that the parameter expects.
                                            Using '1' since it can be converted to String, Numeric
                                            and Boolean.
                                        #>

                                        $exampleParameters.Add($parameterName, ('1' -as $parameterType))
                                    }
                                }
                            }

                            <#
                                If there is a $ConfigurationData variable that was dot-sourced
                                then use that as the configuration data instead of the mocked
                                configuration data.
                            #>

                            if (Get-Item -Path variable:ConfigurationData -ErrorAction 'SilentlyContinue')
                            {
                                $mockConfigurationData = $ConfigurationData
                            }

                            & $exampleCommand.Name @exampleParameters -ConfigurationData $mockConfigurationData -OutputPath 'TestDrive:\' -ErrorAction 'Continue' -WarningAction 'SilentlyContinue' | Out-Null
                        }
                    }
                    else
                    {
                        throw ('The example ''{0}'' does not contain a configuration named ''{1}''.' -f $exampleDescriptiveName, ($commandName -join "', or '"))
                    }

                }
                finally
                {
                    <#
                        Remove the function we dot-sourced so next example file
                        doesn't use the previous Example-function. Using recurse
                        since it saw child functions when copied in helper functions
                        during debugging, it resulted in an interactive prompt.
                    #>

                    Remove-Item -Path "function:$existingCommandName" -ErrorAction 'SilentlyContinue' -Recurse -Force

                    <#
                        Remove the variable $ConfigurationData if it existed in
                        the file we dot-sourced so next example file doesn't use
                        the previous examples configuration.
                    #>

                    Remove-Item -Path 'variable:ConfigurationData' -ErrorAction 'SilentlyContinue'
                }
            } | Should -Not -Throw
        }
    }
}