Lint modified files (but not yet committed) files.

lint-pending.js

require('colors');
const shell = require('shelljs');
const MAX_FILES = 30;

let lintCmd = 'node ./node_modules/eslint/bin/eslint';
let scssCmd = 'node ./node_modules/stylelint/bin/stylelint';

let status = shell.exec('git status --porcelain', { silent: true }).stdout;
let log = s => console.log(`• ${s}`.cyan);

status = status
  .trim()
  .split('\n')
  .reduce((acc, line) => {
    let flags = line
      .substr(0, 2)
      .split('')
      .filter(c => c.trim());
    let names = line.substr(2).trim();
    let name = names.replace(/.*?->\s+/, '');
    acc.push({ flags, name });
    return acc;
  }, []);

let files = status
  .filter(item => !item.flags.includes('D'))
  .map(item => item.name);

let scssFiles = files.filter(name => name.endsWith('scss'));
let jsFiles = files.filter(name => name.endsWith('js'));
let scssCode = 0;
let eslintCode = 0;

// js
if (jsFiles.length > 0) {
  if (jsFiles.length > MAX_FILES) {
    console.error('you have too many js files, sry');
    process.exit(1);
  }
  log(`eslint needed: checking ${jsFiles.length} js files...`);
  eslintCode = shell.exec(lintCmd + ' ' + jsFiles.join(' ')).code;
} else {
  log('no eslint lint needed');
}

// scss
if (scssFiles.length > 0) {
  if (scssFiles.length > MAX_FILES) {
    console.error('you have too many scss files, sry');
    process.exit(2);
  }
  log(`styellint needed: checking ${scssFiles.length} scss files...`);
  scssCode = shell.exec(scssCmd + ' ' + scssFiles.join(' ')).code;
} else {
  log('no stylelint needed');
}

let finalCode = eslintCode || scssCode;
console.log(finalCode ? ':('.red : ':)'.green);
process.exit(finalCode);