每个文件夹生成单独一个文件

/scripts
/scripts/jquery/*.js
/scripts/angularjs/*.js

/scripts
/scripts/jquery.min.js
/scripts/angularjs.min.js

var fs = require('fs'
var path = require('path'
var merge = require('merge-stream'
var gulp = require('gulp'
var concat = require('gulp-concat'
var rename = require('gulp-rename'
var uglify = require('gulp-uglify'

var scriptsPath = 'src/scripts';

function getFolders(dir) {
    return fs.readdirSync(dir)
      .filter(function(file) {
        return fs.statSync(path.join(dir, file)).isDirectory(
      }
}

gulp.task('scripts', function() {
   var folders = getFolders(scriptsPath

   var tasks = folders.map(function(folder) {
      // 拼接成 foldername.js
      // 写入输出
      // 压缩
      // 重命名为 folder.min.js
      // 再一次写入输出
      return gulp.src(path.join(scriptsPath, folder, '/*.js'))
        .pipe(concat(folder + '.js'))
        .pipe(gulp.dest(scriptsPath))
        .pipe(uglify())
        .pipe(rename(folder + '.min.js'))
        .pipe(gulp.dest(scriptsPath)
   }

   return merge(tasks
}