Pentia.Invoke-ConfigurationTransform.Tests.ps1

# Requires https://github.com/pester/Pester: Install-Module Pester -Force -SkipPublisherCheck
Import-Module "$PSScriptRoot\Pentia.Invoke-ConfigurationTransform.psm1" -Force

Describe "Get-PathOfFileToTransform" {
    It "should return the path of the file to transform" {
        # Arrange
        $configurationTransformFilePath = "C:\MySolution\src\Foundation\MyProject\Code\App_Config\MyConfig.Debug.config"
        $webrootOutputPath = "C:\webroot"
        $expectedPath = "C:\webroot\App_Config\MyConfig.config"

        # Act
        $actualPath = Get-PathOfFileToTransform -ConfigurationTransformFilePath $configurationTransformFilePath -WebrootOutputPath $webrootOutputPath

        # Assert
        $actualPath | Should Be $expectedPath
    }
    
    It "should return the path of the Web.config file for XDTs targeting Web.config directly" {
        # Arrange
        $configurationTransformFilePath = "C:\MySolution\src\Foundation\MyProject\Code\Web.Debug.config"
        $webrootOutputPath = "C:\webroot"
        $expectedPath = "C:\webroot\Web.config"

        # Act
        $actualPath = Get-PathOfFileToTransform -ConfigurationTransformFilePath $configurationTransformFilePath -WebrootOutputPath $webrootOutputPath

        # Assert
        $actualPath | Should Be $expectedPath
    }
    
    It "should return the path of the Web.config file for XDTs targeting Web.config by convention" {
        # Arrange
        $configurationTransformFilePath = "C:\MySolution\src\Foundation\MyProject\Code\Web.Feature.WebProject.Debug.config"
        $webrootOutputPath = "C:\webroot"
        $expectedPath = "C:\webroot\Web.config"

        # Act
        $actualPath = Get-PathOfFileToTransform -ConfigurationTransformFilePath $configurationTransformFilePath -WebrootOutputPath $webrootOutputPath

        # Assert
        $actualPath | Should Be $expectedPath
    }
    
    It "should not return the path of the Web.config file due to an incorrect Regex" {
        # Arrange
        $configurationTransformFilePath = "C:\MySolution\src\Foundation\MyProject\Code\App_Config\WebProject.Debug.config"
        $webrootOutputPath = "C:\webroot"
        $expectedPath = "C:\webroot\App_Config\WebProject.config"

        # Act
        $actualPath = Get-PathOfFileToTransform -ConfigurationTransformFilePath $configurationTransformFilePath -WebrootOutputPath $webrootOutputPath

        # Assert
        $actualPath | Should Be $expectedPath
    }
}

Describe "Invoke-ConfigurationTransform" {
    It "can transform XML using XDT" {
        # Arrange
        Set-Content -Path "$TestDrive\test.config" -Value "<?xml version=""1.0"" encoding=""utf-8""?><configuration></configuration>"
        Set-Content -Path "$TestDrive\test.Transform.config" -Value "<configuration xmlns:xdt=""http://schemas.microsoft.com/XML-Document-Transform""><setting xdt:Transform=""Insert"" /></configuration>"
        
        $expectedTransformedContent = "<?xml version=""1.0"" encoding=""utf-8""?><configuration><setting /></configuration>"
        
        # Act
        $transformedXML = Invoke-ConfigurationTransform -XmlFilePath "$TestDrive\test.config" -XdtFilePath "$TestDrive\test.Transform.config"
        
        # Assert
        $transformedXML | Should Be $expectedTransformedContent
    }

    It "throws a helpful exception when a XML node isn't found" {
        # Arrange
        Set-Content -Path "$TestDrive\test.config" -Value "<?xml version=""1.0"" encoding=""utf-8""?><configuration></configuration>"
        Set-Content -Path "$TestDrive\test.Transform.config" -Value "<configuration xmlns:xdt=""http://schemas.microsoft.com/XML-Document-Transform""><does-not-exist><setting xdt:Transform=""Insert"" /></does-not-exist></configuration>"
        $xmlFilePath = "$TestDrive\test.config"
        $xdtFilePath = "$TestDrive\test.Transform.config"

        # Act
        $exception = $null
        try { 
            Invoke-ConfigurationTransform -XmlFilePath $xmlFilePath -XdtFilePath $xdtFilePath
        }
        catch {
            $exception = $_.Exception
        }
        
        # Assert
        $exception.Message | Should Be "Transformation of '$xmlFilePath' failed using transform '$xdtFilePath'. See the inner exception for details."
    }

    It "applies multiple XDTs as expected" {
        # Arrange
        $configurationFilePath = "$TestDrive\test.config"
        Set-Content -Path $configurationFilePath -Value "<?xml version=""1.0"" encoding=""utf-8""?><configuration></configuration>"
        Set-Content -Path "$TestDrive\test.Transform1.config" -Value "<configuration xmlns:xdt=""http://schemas.microsoft.com/XML-Document-Transform""><setting value=""one"" xdt:Transform=""Insert"" /></configuration>"
        Set-Content -Path "$TestDrive\test.Transform2.config" -Value "<configuration xmlns:xdt=""http://schemas.microsoft.com/XML-Document-Transform""><setting value=""two"" xdt:Transform=""Insert"" /></configuration>"
        
        $expectedTransformedContent = "<?xml version=""1.0"" encoding=""utf-8""?><configuration><setting value=""one"" /><setting value=""two"" /></configuration>"
        
        # Act
        Invoke-ConfigurationTransform -XmlFilePath "$TestDrive\test.config" -XdtFilePath "$TestDrive\test.Transform1.config" | Set-Content -Path $configurationFilePath
        Invoke-ConfigurationTransform -XmlFilePath "$TestDrive\test.config" -XdtFilePath "$TestDrive\test.Transform2.config" | Set-Content -Path $configurationFilePath
        $transformedXML = Get-Content -Path $configurationFilePath
        
        # Assert
        $transformedXML | Should Be $expectedTransformedContent
    }

    It "resolves relative paths against `$PWD" {
        # Arrange
        Set-Content -Path "$TestDrive\test.config" -Value "<?xml version=""1.0"" encoding=""utf-8""?><configuration></configuration>"
        Set-Content -Path "$TestDrive\test.Transform.config" -Value "<configuration xmlns:xdt=""http://schemas.microsoft.com/XML-Document-Transform""><setting xdt:Transform=""Insert"" /></configuration>"
        
        $expectedTransformedContent = "<?xml version=""1.0"" encoding=""utf-8""?><configuration><setting /></configuration>"
        
        # Act
        Push-Location $TestDrive
        try {
            $transformedXML = Invoke-ConfigurationTransform -XmlFilePath ".\test.config" -XdtFilePath ".\test.Transform.config" 
        }
        finally {
            Pop-Location            
        }

        # Assert
        $transformedXML | Should Be $expectedTransformedContent
    }
}

Describe "Invoke-AllConfigurationTransforms" {

    function Get-FileEncoding {
        param (
            [Parameter(Mandatory = $true)]
            [string]$Path
        )
        $bytes = [byte[]](Get-Content $Path -Encoding byte -ReadCount 4 -TotalCount 4)
    
        if (-not $bytes) { throw "File '$Path' is empty." }
    
        switch -regex ('{0:x2}{1:x2}{2:x2}{3:x2}' -f $bytes[0], $bytes[1], $bytes[2], $bytes[3]) {
            '^efbbbf' { return 'utf8' }
            '^2b2f76' { return 'utf7' }
            '^fffe' { return 'unicode' }
            '^feff' { return 'bigendianunicode' }
            '^0000feff' { return 'utf32' }
            default { return 'ascii' }
        }
    }

    It "should save XML with missing XML declaration as UTF-16" {
        # Arrange
        New-Item -Path "$TestDrive\App_Config" -ItemType Directory -Force
        $testFilePath = "$TestDrive\App_Config\test.config"
        Set-Content -Path $testFilePath -Value "<configuration></configuration>"
        Set-Content -Path "$TestDrive\App_Config\test.MyBuildConfiguration.config" -Value "<configuration xmlns:xdt=""http://schemas.microsoft.com/XML-Document-Transform""><setting xdt:Transform=""Insert"" /></configuration>"

        # Act
        Invoke-AllConfigurationTransforms -SolutionOrProjectRootPath "$TestDrive" -WebrootOutputPath "$TestDrive" -BuildConfiguration "MyBuildConfiguration"
        
        # Assert
        [xml]$xml = Get-Content -Path $testFilePath
        $xml.FirstChild.Encoding | Should Be "utf-16"
        $xml.configuration.setting | Should Not Be $null
        Get-FileEncoding -Path $testFilePath | Should Be "unicode"
    }

    It "should save XML file with existing XML declaration as correct encoding" {
        # Arrange
        New-Item -Path "$TestDrive\App_Config" -ItemType Directory -Force
        $testFilePath = "$TestDrive\App_Config\test.config"
        Set-Content -Path $testFilePath -Value "<?xml version=""1.0"" encoding=""utf-8""?><configuration></configuration>"
        Set-Content -Path "$TestDrive\App_Config\test.MyBuildConfiguration.config" -Value "<configuration xmlns:xdt=""http://schemas.microsoft.com/XML-Document-Transform""><setting xdt:Transform=""Insert"" /></configuration>"

        # Act
        Invoke-AllConfigurationTransforms -SolutionOrProjectRootPath "$TestDrive" -WebrootOutputPath "$TestDrive" -BuildConfiguration "MyBuildConfiguration"
        
        # Assert
        [xml]$xml = Get-Content -Path $testFilePath
        $xml.FirstChild.Encoding | Should Be "utf-8"
        $xml.configuration.setting | Should Not Be $null
        Get-FileEncoding -Path $testFilePath | Should Be "utf8"
    }

    foreach ($webrootOutputPathVariant in @($TestDrive, "$TestDrive\")) {
    
        It "should use the `$WebrootOutputPath as a fallback when `$SolutionOrProjectRootPath is null or empty" {
            # Arrange
            $testFilePath = "$TestDrive\test.config"
            Set-Content -Path $testFilePath -Value "<?xml version=""1.0"" encoding=""utf-8""?><configuration></configuration>"
            Set-Content -Path "$TestDrive\test.MyBuildConfiguration.config" -Value "<configuration xmlns:xdt=""http://schemas.microsoft.com/XML-Document-Transform""><setting xdt:Transform=""Insert"" /></configuration>"

            # Act
            Invoke-AllConfigurationTransforms -WebrootOutputPath $webrootOutputPathVariant -BuildConfiguration "MyBuildConfiguration"
        
            # Assert
            [xml]$xml = Get-Content -Path $testFilePath
            $xml.FirstChild.Encoding | Should Be "utf-8"
            $xml.configuration.setting | Should Not Be $null
            Get-FileEncoding -Path $testFilePath | Should Be "utf8"
        }
    }
}

Describe "Configuration transformation integration test" {    
    It "applies configuration transforms to the correct configuration file in the webroot" {
        # Arrange
        New-Item -Path "$TestDrive\WebsiteRoot\" -ItemType Directory
        New-Item -Path "$TestDrive\WebsiteRoot\App_Config" -ItemType Directory
        Set-Content -Path "$TestDrive\WebsiteRoot\App_Config\MyConfig.config" -Value "<?xml version=""1.0"" encoding=""utf-8""?><configuration></configuration>"
        $webrootOutputPath = "$TestDrive\WebsiteRoot\"
        
        New-Item -Path "$TestDrive\ProjectRoot" -ItemType Directory
        New-Item -Path "$TestDrive\ProjectRoot\App_Config" -ItemType Directory
        Set-Content -Path "$TestDrive\ProjectRoot\App_Config\MyConfig.Debug.config" -Value "<configuration xmlns:xdt=""http://schemas.microsoft.com/XML-Document-Transform""><setting xdt:Transform=""Insert"" /></configuration>"
        $configurationTransformFilePath = "$TestDrive\ProjectRoot\App_Config\MyConfig.Debug.config"
        
        $expectedTransformedContent = "<?xml version=""1.0"" encoding=""utf-8""?><configuration><setting /></configuration>"

        # Act
        $pathOfFileToTransform = Get-PathOfFileToTransform -ConfigurationTransformFilePath $configurationTransformFilePath -WebrootOutputPath $webrootOutputPath
        $transformedContent = Invoke-ConfigurationTransform -XmlFilePath $pathOfFileToTransform -XdtFilePath $configurationTransformFilePath
        $transformedContent | Out-File $pathOfFileToTransform -Encoding utf8

        # Assert
        $transformedContent = Get-Content -Path "$TestDrive\WebsiteRoot\App_Config\MyConfig.config"
        $transformedContent | Should Be $expectedTransformedContent
    }
}