code: function find(test, paths, callback, one) {
    var state = {
      broken: false,
      checked: [],
      test: augment(test)
    }
  
    if (!callback) {
      callback = paths
      paths = [process.cwd()]
    } else if (typeof paths === 'string') {
      paths = [paths]
    }
  
    return visitAll(state, paths, null, one, done)
  
    function done(result) {
      callback(null, one ? result[0] || null : result)
    }
  }
docs: Find applicable files.