Gulpfile snippet for SASS and Bootstrap

gulpfile-sass.js

"use strict"
require("babel-polyfill")

const argv = require('minimist')(process.argv.slice(2))
import gulp from 'gulp'
import gutil from 'gulp-util'
import sass from 'gulp-sass'
import concat from 'gulp-concat'
import gulpif from 'gulp-if'
import autoprefixer from 'gulp-autoprefixer'
import sourcemaps from 'gulp-sourcemaps'
import minifyCss from 'gulp-minify-css'
import os from 'os'
import batch from 'gulp-batch'
import plumber from 'gulp-plumber'

const plumberh = function (err) {
    gutil.beep()
    console.log(err)
    this.emit('end')
}

const config = {
    bootstrap: "./node_modules/bootstrap-sass",
    scss: "src/style/**/*.scss",
}

const enabled = {
    // disable source maps when `--production`
    maps: !argv.production,
}

gulp.task('style', () => {
    return gulp.src(config.scss)
        .pipe(plumber({errorHandler: plumberh}))
        .pipe(gulpif(enabled.maps, sourcemaps.init()))
        .pipe(sass({includePaths: [config.bootstrap + '/assets/stylesheets']}).on('error', sass.logError))
        .pipe(concat("main.css"))
        .pipe(autoprefixer({
            browsers: [
                'last 2 versions',
                'ie 8',
                'ie 9',
                'android 2.3',
                'android 4',
                'opera 12'
            ]
        }))
        .pipe(minifyCss({
            advanced: false,
            rebase: false
        }))
        .pipe(gulpif(enabled.maps, sourcemaps.write(".")))
        .pipe(gulp.dest('dist/style'))
})

gulp.task('watch', () => {
    gulp.watch([config.scss], batch((events, done) => {
        gulp.start('style', done)
    }))
})