newGulpFile = (filename, code) => {
var src = require('stream').Readable({ objectMode: true })
src._read = function () {
this.push(new gutil.File({
cwd: '',
base: '',
path: filename,
contents: new Buffer(code)
}))
this.push(null)
}
return src
}
newGulpFile(`a.js`, 'console.log("这里是要输出到文件的内容")').pipe(gulp.dest('/dist'))