Additional reporters

[Gijsreyn]

As a user implementing the markdown-link-check in CI pipelines, it's helpful to have additional reporters like JUnit/XUnit to easily report on. The #364 PR addresses the JUnit reporter as additional option to the CLI, but this was later reverted.

Now I have to fallback to using regex and some PowerShell and convert it myself:

# Simple regex
$successPattern = [regex]::new('\[✓\] (http[^\s]+)')
$deadPattern = [regex]::new('\[✖\] (http[^\s]+) → Status: (\d+)')

# Do transformation on content generated and then use the following function to generate JUnit
function ConvertTo-JUnitXml {
    [CmdletBinding()]
    param (
        [Parameter(Mandatory = $true)]
        [psobject[]]$InputObject
    )

    # Create XML document
    $xml = New-Object System.Xml.XmlDocument
    $xmlDeclaration = $xml.CreateXmlDeclaration("1.0", "UTF-8", $null)
    $xml.AppendChild($xmlDeclaration) | Out-Null

    # Create root element
    $root = $xml.CreateElement("testsuites")
    $root.SetAttribute("name", "Test run")
    $root.SetAttribute("tests", $InputObject.Count.ToString())
    $root.SetAttribute("failures", ($InputObject | Where-Object { $_.Status -eq 'Failure' }).Count.ToString())
    $root.SetAttribute("errors", "0")
    $root.SetAttribute("skipped", "0")
    $root.SetAttribute("assertions", "0")
    $root.SetAttribute("time", "0")
    $root.SetAttribute("timestamp", (Get-Date).ToString("yyyy-MM-ddTHH:mm:ss"))
    $xml.AppendChild($root) | Out-Null

    # Create a testsuite element
    $testsuite = $xml.CreateElement("testsuite")
    $testsuite.SetAttribute("name", "Brokenlink.Assertion")
    $testsuite.SetAttribute("time", "0")
    $root.AppendChild($testsuite) | Out-Null

    foreach ($item in $InputObject) {
        $testcase = $xml.CreateElement("testcase")
        $testcase.SetAttribute("classname", $item.URL)
        $testcase.SetAttribute("name", $item.URL)
        $testcase.SetAttribute("time", "0")

        if ($item.Status -eq 'Failure') {
            $failure = $xml.CreateElement("failure")
            $failure.SetAttribute("message", "Status Code: $($Item.StatusCode)")
            $failure.SetAttribute("type", "BrokenlinkError")
            $testcase.AppendChild($failure) | Out-Null
        }

        $testsuite.AppendChild($testcase) | Out-Null
    }

    return $xml.OuterXml
}