gulpfile.js

// Requis
var gulpfile = require('gulp');

// Include plugins
var plugins = require('gulp-load-plugins')(); // tous les plugins de package.json

// Variables de chemins
const cssSource = 'Source/admin/src/scss/',
      cssDestination = 'Source/admin/assets/styles/',
      jsSource = 'Source/admin/src/js/',
      jsDestination = 'Source/admin/assets/scripts/'

gulpfile.task('jsMinifier', function(done) {
    gulpfile.src(jsSource+"*.js") // path to your files
        .pipe(plugins.concat("main.js"))
        .pipe(plugins.minify({
            ext:{
                src:'-debug.js',
                min:'.min.js'
            }
        }))
        .pipe(gulpfile.dest(jsDestination));
    done()
});

// gulpfile.task('jsLint', function(done) {
//     gulpfile.src(jsSource+"/**/*.js") // path to your files
//         .pipe(plugins.jshint())
//         .pipe(plugins.jshint.reporter()); // Dump results
//     done()
// })

gulpfile.task('sass', function() {
    return gulpfile.src(cssSource + 'main.scss')
        .pipe(plugins.sass().on('error', plugins.sass.logError))
        .pipe(plugins.autoprefixer())
        .pipe(gulpfile.dest(cssDestination))
});

gulpfile.task('cssMinfier', function() {
    return gulpfile.src(cssDestination + 'main.css')
        .pipe(plugins.csso())
        .pipe(plugins.rename({
            'suffix': '.min'
        }))
        .pipe(gulpfile.dest(cssDestination))
});

gulpfile.task('js', gulpfile.series('jsMinifier'))
gulpfile.task('css', gulpfile.series('sass', 'cssMinfier'))
gulpfile.task('watch', function() {
    gulpfile.watch('./Source/admin/src/js/*.js', gulpfile.series('js'))
    gulpfile.watch('./Source/admin/src/scss/**/*.scss', gulpfile.series('css'))
});

gulpfile.task('default', gulpfile.series('js','css','watch'));