.github/workflows/main.yml

@@ -0,0 +1,18 @@
+name: CI
+on:
+  - push
+  - pull_request
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        node-version: [10.x, 12.x, 14.x, 15.x]
+
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-node@v1
+        with:
+          node-version: ${{ matrix.node-version }}
+      - run: npm install
+      - run: npm test

index.d.ts

@@ -2,4 +2,6 @@ export function clean(rut: string): string;
 
 export function validate(rut: string): boolean;
 
-export function format(rut: string): string;
+export function format(rut: string): string;
+
+export function getCheckDigit(rut: string): string;

index.js

@@ -1,5 +1,3 @@
-'use strict'
-
 function clean (rut) {
   return typeof rut === 'string'
     ? rut.replace(/^0+|[^0-9kK]+/g, '').toUpperCase()
@@ -10,34 +8,69 @@ function validate (rut) {
   if (typeof rut !== 'string') {
     return false
   }
+
+  // if it starts with 0 we return false
+  // so a rut like 00000000-0 will not pass
+  if (/^0+/.test(rut)) {
+    return false
+  }
+
   if (!/^0*(\d{1,3}(\.?\d{3})*)-?([\dkK])$/.test(rut)) {
     return false
   }
 
   rut = clean(rut)
 
-  var t = parseInt(rut.slice(0, -1), 10)
-  var m = 0
-  var s = 1
+  let t = parseInt(rut.slice(0, -1), 10)
+  let m = 0
+  let s = 1
 
   while (t > 0) {
-    s = (s + (t % 10) * (9 - m++ % 6)) % 11
+    s = (s + (t % 10) * (9 - (m++ % 6))) % 11
     t = Math.floor(t / 10)
   }
 
-  var v = s > 0 ? '' + (s - 1) : 'K'
+  const v = s > 0 ? '' + (s - 1) : 'K'
   return v === rut.slice(-1)
 }
 
 function format (rut) {
   rut = clean(rut)
 
-  var result = rut.slice(-4, -1) + '-' + rut.substr(rut.length - 1)
-  for (var i = 4; i < rut.length; i += 3) {
+  let result = rut.slice(-4, -1) + '-' + rut.substr(rut.length - 1)
+  for (let i = 4; i < rut.length; i += 3) {
     result = rut.slice(-3 - i, -i) + '.' + result
   }
 
   return result
 }
 
-module.exports = { validate: validate, clean: clean, format: format }
+function getCheckDigit (input) {
+  const rut = Array.from(clean(input), Number)
+
+  if (rut.length === 0 || rut.includes(NaN)) {
+    throw new Error(`"${input}" as RUT is invalid`)
+  }
+
+  const modulus = 11
+  const initialValue = 0
+  const sumResult = rut
+    .reverse()
+    .reduce(
+      (accumulator, currentValue, index) =>
+        accumulator + currentValue * ((index % 6) + 2),
+      initialValue
+    )
+
+  const checkDigit = modulus - (sumResult % modulus)
+
+  if (checkDigit === 10) {
+    return 'K'
+  } else if (checkDigit === 11) {
+    return '0'
+  } else {
+    return checkDigit.toString()
+  }
+}
+
+module.exports = { validate, clean, format, getCheckDigit }

package.json

@@ -1,16 +1,19 @@
 {
   "name": "rut.js",
-  "version": "1.0.2",
+  "version": "2.0.0",
   "description": "Sencilla y pequeña libreria para validar y dar formato al RUT",
   "license": "MIT",
   "repository": "jlobos/rut.js",
-  "author": "Jesus Lobos <jlobitu@gmail.com> (https://jlobos.com/)",
+  "author": {
+    "name": "Jesus Lobos",
+    "email": "jlobitu@gmail.com"
+  },
   "main": "index.js",
   "scripts": {
     "test": "standard && ava"
   },
   "engines": {
-    "node": ">=4"
+    "node": ">=10"
   },
   "files": [
     "index.js",
@@ -24,7 +27,7 @@
     "browser"
   ],
   "devDependencies": {
-    "ava": "^2.3.0",
-    "standard": "^14.1.0"
+    "ava": "^3.15.0",
+    "standard": "^16.0.3"
   }
 }

readme.md

@@ -1,14 +1,11 @@
 # rut.js 🇨🇱
 
-[![Build Status](https://travis-ci.org/jlobos/rut.js.svg?branch=master)](https://travis-ci.org/jlobos/rut.js)
-[![styled with prettier](https://img.shields.io/badge/styled_with-prettier-ff69b4.svg)](https://github.com/prettier/prettier)
+Sencilla y pequeña libreria para validar y dar formato al RUT. Funciona en Node.js y Navegadores (Webpack, Browserify, etc.)
 
-Sencilla y pequeña libreria para validar y dar formato al RUT. Funciona en Node.js y Navegadores (Webpack, Browserify)
-
-> Utilizada en producción para manejar mas de 13 millones de chilenos en [Rutify – Rutificador](https://rutify.cl/) 
+> Utilizada en producción para manejar mas de 13 millones de chilenos en [~Rutify – Rutificador~](https://rutify.cl/)
 
 ```js
-const { validate, clean, format } = require('rut.js')
+const { validate, clean, format, getCheckDigit } = require('rut.js')
 
 // true
 validate('18.972.631-7')
@@ -48,6 +45,12 @@ format('18.972.631-7')  // '18.972.631-7'
 format('189726317')     // '18.972.631-7'
 format('18*972*631*7')  // '18.972.631-7'
 format('9068826-k')     // '9.068.826-K'
+
+/**
+ * Obtener el dígito verificador
+ */
+getCheckDigit('18.972.631')  // '7'
+getCheckDigit('9068826')     // 'K'
 ```
 
 ## Instalación
@@ -62,7 +65,3 @@ npm install --save rut.js
 npm install
 npm test
 ```
-
-## License
-
-MIT © [Jesus Lobos](https://jlobos.com/)

test.js

@@ -1,7 +1,7 @@
-import test from 'ava'
-import { clean, validate, format } from './index'
+const test = require('ava')
+const { clean, validate, format, getCheckDigit } = require('./index')
 
-test('clean', t => {
+test('clean', (t) => {
   t.is(clean('189726317'), '189726317')
   t.is(clean('18.972.631-7'), '189726317')
   t.is(clean('12.345.678-k'), '12345678K')
@@ -10,7 +10,7 @@ test('clean', t => {
   t.is(clean('00000189726317'), '189726317')
 })
 
-test('validate', t => {
+test('validate', (t) => {
   t.true(validate('18.972.631-7'))
   t.true(validate('18972631-7'))
   t.true(validate('189726317'))
@@ -30,9 +30,40 @@ test('validate', t => {
   t.false(validate(0))
 })
 
-test('format', t => {
+test('format', (t) => {
   t.is(format('18.972.631-7'), '18.972.631-7')
   t.is(format('189726317'), '18.972.631-7')
   t.is(format('18*972*631*7'), '18.972.631-7')
   t.is(format('9068826-k'), '9.068.826-K')
 })
+
+test('does not validate rut with 0 on most right digit', t => {
+  t.false(validate('00.000.000-0'))
+  t.false(validate('00000000-0'))
+  t.false(validate('0000000000000000000000-0'))
+})
+
+test('getCheckDigit', (t) => {
+  t.is(getCheckDigit('18.657.499-'), '0')
+  t.is(getCheckDigit('6.383.287'), '1')
+  t.is(getCheckDigit('13.466.350'), '2')
+  t.is(getCheckDigit('3,966,753'), '3')
+  t.is(getCheckDigit('4132650'), '6')
+  t.is(getCheckDigit('18972631'), '7')
+  t.is(getCheckDigit('9068826'), 'K')
+  t.is(getCheckDigit('14774764'), '0')
+})
+
+test('getCheckDigit: pass character like a RUT', (t) => {
+  const { message } = t.throws(() => {
+    getCheckDigit('Felipe Camiroaga')
+  })
+  t.is(message, '"Felipe Camiroaga" as RUT is invalid')
+})
+
+test('getCheckDigit: pass 0 like a RUT', (t) => {
+  const { message } = t.throws(() => {
+    getCheckDigit(0)
+  })
+  t.is(message, '"0" as RUT is invalid')
+})