var downloadArchive = function()

in make-util.js [372:438]
56 lines of code
14 McCabe index (conditional complexity)

var downloadArchive = function (url, omitExtensionCheck) {
    // validate parameters
    if (!url) {
        throw new Error('Parameter "url" must be set.');
    }

    var isZip;
    var isTargz;
    if (omitExtensionCheck) {
        isZip = true;
    }
    else {
        if (url.match(/\.zip$/)) {
            isZip = true;
        }
        else if (url.match(/\.tar\.gz$/) && (process.platform == 'darwin' || process.platform == 'linux')) {
            isTargz = true;
        }
        else {
            throw new Error('Unexpected archive extension');
        }
    }

    // skip if already downloaded and extracted
    var scrubbedUrl = url.replace(/[/\:?]/g, '_');
    var targetPath = path.join(downloadPath, 'archive', scrubbedUrl);
    var marker = targetPath + '.completed';
    if (!test('-f', marker)) {
        // download the archive
        var archivePath = downloadFile(url);
        console.log('Extracting archive: ' + url);

        // delete any previously attempted extraction directory
        if (test('-d', targetPath)) {
            rm('-rf', targetPath);
        }

        // extract
        mkdir('-p', targetPath);
        if (isZip) {
            if (process.platform == 'win32') {
                let escapedFile = archivePath.replace(/'/g, "''").replace(/"|\n|\r/g, ''); // double-up single quotes, remove double quotes and newlines
                let escapedDest = targetPath.replace(/'/g, "''").replace(/"|\n|\r/g, '');

                let command = `$ErrorActionPreference = 'Stop' ; try { Add-Type -AssemblyName System.IO.Compression.FileSystem } catch { } ; [System.IO.Compression.ZipFile]::ExtractToDirectory('${escapedFile}', '${escapedDest}')`;
                run(`powershell -Command "${command}"`);
            } else {
                run(`unzip ${archivePath} -d ${targetPath}`);
            }
        }
        else if (isTargz) {
            var originalCwd = process.cwd();
            cd(targetPath);
            try {
                run(`tar -xzf "${archivePath}"`);
            }
            finally {
                cd(originalCwd);
            }
        }

        // write the completed marker
        fs.writeFileSync(marker, '');
    }

    return targetPath;
}