问gulp ruby-sass错误不是一个函数

EN

 [04:57:11] TypeError: undefined is not a function
at DestroyableTransform.Readable.pipe [as _pipe] (E:\Do\angular-jspm-todo\no
de_modules\gulp-autoprefixer\node_modules\through2\node_modules\readable-stream\
lib\_stream_readable.js:516:8)
    at DestroyableTransform.pipe2 (E:\Do\angular-jspm-todo\node_modules\gulp-plu
mber\index.js:70:20)
    at Gulp.<anonymous> (E:\Do\angular-jspm-todo\gulp\tasks\sass.js:15:8)
    at module.exports (E:\Do\angular-jspm-todo\node_modules\gulp\node_modules\or
chestrator\lib\runTask.js:34:7)
    at Gulp.Orchestrator._runTask (E:\Do\angular-jspm-todo\node_modules\gulp\nod
e_modules\orchestrator\index.js:273:3)
    at Gulp.Orchestrator._runStep (E:\Do\angular-jspm-todo\node_modules\gulp\nod
e_modules\orchestrator\index.js:214:10)
    at E:\Do\angular-jspm-todo\node_modules\gulp\node_modules\orchestrator\index
.js:279:18
    at finish (E:\Do\angular-jspm-todo\node_modules\gulp\node_modules\orchestrat
or\lib\runTask.js:21:8)
    at module.exports (E:\Do\angular-jspm-todo\node_modules\gulp\node_modules\or
chestrator\lib\runTask.js:60:3)
    at Gulp.Orchestrator._runTask (E:\Do\angular-jspm-todo\node_modules\gulp\nod
e_modules\orchestrator\index.js:273:3)
[04:57:11] gulp-ruby-sass stderr: OptionParser::InvalidOption: invalid option: -
-sourcemap-path=app/css
  Use --trace for backtrace.
E:\Do\angular-jspm-todo\node_modules\gulp-autoprefixer\node_modules\through2\nod
e_modules\readable-stream\lib\_stream_readable.js:523
    dest.end();
         ^
TypeError: undefined is not a function
    at DestroyableTransform.onend (E:\Do\angular-jspm-todo\node_modules\gulp-aut
oprefixer\node_modules\through2\node_modules\readable-stream\lib\_stream_readabl
e.js:523:10)
    at DestroyableTransform.g (events.js:199:16)
    at DestroyableTransform.emit (events.js:129:20)
    at E:\Do\angular-jspm-todo\node_modules\gulp-autoprefixer\node_modules\throu
gh2\node_modules\readable-stream\lib\_stream_readable.js:965:16
    at process._tickCallback (node.js:355:11)

    sass: {
        src:  app + '/scss/**/*.{sass,scss}',
        dest: app + '/css',
  options: {
    noCache: true,
    compass: false,
    sourcemap: true,
    sourcemapPath: app+'/css'
  }
},
autoprefixer: {
  browsers: [
    'last 2 versions',
    'safari 5',
    'ie 8',
    'ie 9',
    'opera 12.1',
    'ios 6',
    'android 4'
  ],
  cascade: true
},
scsslint: {
  src: [
    app + '/scss/**/*.{sass,scss}',
    ]
}

gulp.task('sass',function(){
return sass(config.sass.src,config.sass.options)
           .pipe(plumber({errorHandler:notify.onError('<%= error.message %>')}))
           .pipe(sourcemaps.init())
           .pipe(autoprefixer(config.autoprefixer))
           .pipe(filter)
           .pipe(sourcemaps.write('.',{includeContent:false}))
           .pipe(filter.restore())
           .pipe(gulp.dest(config.sass.dest));
});

var gulp = require('gulp');
var scsslint = require('gulp-scss-lint');
var config   = require('../config').scsslint;

gulp.task('scsslint',function(){
    return gulp.src(config.src)
               .pipe(scsslint(config.options))
});

 gulp.task('serve',['jshint','scsslint','sass'],function(){
browserSync(config);