gulpfile.js

const gulp = require('gulp');
const eslint = require('gulp-eslint');
const runSequence = require('run-sequence');
const jest = require('gulp-jest').default;
const prettierEslint = require('gulp-prettier-eslint');
const nodemon = require('gulp-nodemon');

gulp.task('test', () =>
  gulp.src('__tests__').pipe(jest({
    coverage: true,
  })));

gulp.task('lint', () =>
  gulp
    .src(['!node_modules/**', 'src/**/*.js', '__tests__/**/*.js'])
    .pipe(eslint())
    .pipe(eslint.format())
    .pipe(eslint.failAfterError()));

gulp.task('prettier', () => {
  gulp
    .src(['!node_modules/**', 'src/**/*.js', '__tests__/**/*.js'], {
      base: './',
    })
    .pipe(prettierEslint())
    .pipe(gulp.dest('./'));
});

gulp.task('prettify', (done) => {
  runSequence('prettier', 'lint', done);
});

gulp.task('watch', () => {
  nodemon({
    script: 'server.js',
    ext: 'js',
  });
});