问Gulp JS不输出CSS文件

EN

// gulpfile.js

// --- INIT
var gulp = require('gulp'),
    util = require('gulp-util'),
    less = require('gulp-less'), // compiles less to CSS
    minify = require('gulp-minify-css'), // minifies CSS
    concat = require('gulp-concat'),
    rename = require('gulp-rename'),
    uglify = require('gulp-uglify'); // minifies JS

// Paths variables
var paths = {
    'dev': {
        'less': './laravel/public/assets/less/'
    },
    'assets': {
        'css': './laravel/public/assets/css/ ',
        'js': './laravel/public/assets/js/',
        'vendor': './laravel/public/assets/bower_vendor/'
    }

};

// --- TASKS

// Auth CSS
gulp.task('auth.css', function(){
   return gulp.src(paths.dev.less + 'auth.less')
       .pipe(less().on('error', util.log))
       .pipe(gulp.dest(paths.assets.css))
       .pipe(minify({keepSpecialComments:0}))
       .pipe(rename({suffix: '.min'}))
       .pipe(gulp.dest(paths.assets.css));
});

// --- WATCH

// --- DEFAULT
gulp.task('default', ['auth.css']);