password-validator/src/validationMessages.js

Validates password according to flexible and intuitive specifications

module.exports = function (method, arg, inverted) {
  const msgList = inverted ? negativeMessages : positiveMessages;
  return msgList[method] && msgList[method](arg);
};

const positiveMessages = {
  min: (num) => `The string should have a minimum length of ${num} character${pluralify(num)}`,
  max: (num) => `The string should have a maximum length of ${num} character${pluralify(num)}`,
  letters: (num = 1) => `The string should have a minimum of ${num} letter${pluralify(num)}`,
  digits: (num = 1) => `The string should have a minimum of ${num} digit${pluralify(num)}`,
  uppercase: (num = 1) => `The string should have a minimum of ${num} uppercase letter${pluralify(num)}`,
  lowercase: (num = 1) => `The string should have a minimum of ${num} lowercase letter${pluralify(num)}`,
  symbols: (num = 1) => `The string should have a minimum of ${num} symbol${pluralify(num)}`,
  spaces: (num = 1) => `The string should have a minimum of ${num} space${pluralify(num)}`,
  oneOf: (list) => `The string should be ${list.length > 1 ? `one of ${list.slice(0, -1).join(', ')} and ` : ''}${list[list.length - 1]}`,
  has: (pattern) => `The string should have pattern '${pattern}'`,
  not: (pattern) => `The string should not have pattern '${pattern}'`,
  usingPlugin: (fn) => `The string should not violate ${fn.name || 'plugin'}`,
};

const negativeMessages = {
  min: (num) => `The string should have a maximum length of ${num} character${pluralify(num)}`,
  max: (num) => `The string should have a minimum length of ${num} character${pluralify(num)}`,
  letters: (num = 0) => `The string should ${num === 0 ? 'not have' : `have a maximum of ${num}`} letter${pluralify(num)}`,
  digits: (num = 0) => `The string should ${num === 0 ? 'not have' : `have a maximum of ${num}`} digit${pluralify(num)}`,
  uppercase: (num = 0) => `The string should ${num === 0 ? 'not have' : `have a maximum of ${num}`} uppercase letter${pluralify(num)}`,
  lowercase: (num = 0) => `The string should ${num === 0 ? 'not have' : `have a maximum of ${num}`} lowercase letter${pluralify(num)}`,
  symbols: (num = 0) => `The string should ${num === 0 ? 'not have' : `have a maximum of ${num}`} symbol${pluralify(num)}`,
  spaces: (num = 0) => `The string should ${num === 0 ? 'not have' : `have a maximum of ${num}`} space${pluralify(num)}`,
  oneOf: (list) => `The string should not be ${list.length > 1 ? `one of ${list.slice(0, -1).join(', ')} and ` : ''}${list[list.length - 1]}`,
  has: (pattern) => `The string should not have pattern '${pattern}'`,
  not: (pattern) => `The string should have pattern '${pattern}'`,
  usingPlugin: (fn) => `The string should violate ${fn.name || 'plugin'}`,
};

function pluralify(num) {
  return num === 1 ? '' : 's';
}