Validating an object without 'if's

validators.js

const validEmptyField = ({ field, label }) => ({
  match: (data) => {
    const value = data && data[field]
    return value === null || value === undefined || (typeof value === 'string' && value === '')
  },
  message: () => `${label} is required`
})

const validEmailConfirmation = {
  match: ({ email, confirmationEmail }) => email && email !== confirmationEmail,
  message: () => 'Email has to equal its confirmation'
}

const validIsAdult = {
  match: ({ age }) => age && age < 19,
  message: ({ age }) => `The age is ${age}, wait ${18 - age} years.`
}

const validators = [
  validEmptyField({ field: 'name', label: 'Name' }),
  validEmptyField({ field: 'age', label: 'Age' }),
  validEmptyField({ field: 'email', label: 'Email' }),
  validIsAdult,
  validEmailConfirmation
]

const bruno = {
  name: 'Bruno',
  age: 10,
  email: 'bruno@empresadobruno.com',
  confirmationEmail: 'bruno@empresadobruno.com'
}

const validate = (data, validators) =>
  validators
    .filter(validator => validator.match(data))
    .map(validator => validator.message(data))
    .join(',')

console.log(validate(bruno, validators))