toBoolean.js

var trim = require('./trim');

function boolMatch(s, matchers) {
  var i, matcher, down = s.toLowerCase();
  matchers = [].concat(matchers);
  for (i = 0; i < matchers.length; i += 1) {
    matcher = matchers[i];
    if (!matcher) continue;
    if (matcher.test && matcher.test(s)) return true;
    if (matcher.toLowerCase() === down) return true;
  }
}

module.exports = function toBoolean(str, trueValues, falseValues) {
  if (typeof str === "number") str = "" + str;
  if (typeof str !== "string") return !!str;
  str = trim(str);
  if (boolMatch(str, trueValues || ["true", "1"])) return true;
  if (boolMatch(str, falseValues || ["false", "0"])) return false;
};