No binary for PhantomJS browser on your platform. Please, set "PHANTOMJS_BIN"

用 karma start test/karma.conf.js 跑单元测试时候，karma报错如下：

No binary for PhantomJS browser on your platform.   Please, set "PHANTOMJS_BIN" 

解决方案：

(sudo ) npm install karma-phantomjs-launcher即可解决此问题