shell bypass 403
// on windows, either \ or / are valid directory separators.
// on unix, \ is a valid character in filenames.
// so, on windows, and only on windows, we replace all \ chars with /,
// so that we can use / as our one and only directory separator char.
const platform = process.env.TESTING_TAR_FAKE_PLATFORM || process.platform
module.exports = platform !== 'win32' ? p => p
: p => p && p.replace(/\\/g, '/')