Error while installing mocha

I’m trying to install practicalmeteor:mocha in Meteor 1.4 and getting the following error.

/Users/.meteor/packages/ecmascript/.0.5.8.xrqpml++os+web.browser+web.cordova/plugin.compile-ecmascript.os/npm/node_modules/meteor/promise/node_modules/meteor-promise/promise_server.js:165
throw error;
      ^
Error: EIO: i/o error, read
    at Error (native)
```

My app is running fine if I don't add this package, though.
How can I figure it how where it is getting stuck?

TIA