jStat npm import with Meteor, conflict between test and production

Hi,

I am building a Meteor app, and I am using the jStat library. I have some weird trouble with imports, using Meteor 1.3.

When I use the import { jStat } from jStat, my server test are passing and jStat is correctly loaded. But it does not work on the client side and on client test, jStat object is undefined.

When I use the import 'jStat' syntax, that’s the opposite… jStat is undefined in my server test, but defined in my template and my client test.

I did install meteor-node-stubs, it did not change anything.
I also tried import * as jStat from jStat, but it only has the same effect than import jStat from 'jStat'.

It seems to be an issue related to jStat itself, that has a weird loading behaviour (https://github.com/jstat/jstat#module-loaders).

Here are my files :

/imports/math/rates.js

import { jStat } from 'jStat';

/**
 * Confidence interval calculation on proportions
 * @return {[type]} [description]
 */
export const Rates = function(){
    var self = this;

    self.ualpha = function(alpha){
        var mean = 0;
        var std =1;
        return jStat.normal.inv(1-alpha/2,0,1);
    };
    return self;
}();

/imports/math/rates.tests.js (the test file for rates.js)

import { Meteor } from 'meteor/meteor';
import { Template } from 'meteor/templating';
import { Events } from '/collections/events.js';
import { Stubs } from '/imports/testing/stubs.js';
import { TestHelpers } from '/imports/testing/helpers.js';
import { assert } from 'chai';
import { Rates } from '/imports/math/rates.js';

describe('Rates Helpers', () => {
    beforeEach(()=>{
    });
    it("Should compute ualpha",()=>{
        var eps = 10e-7;
        assert.approximately(1.959964,Rates.ualpha(0.05),eps);
        assert.approximately(1.644854, Rates.ualpha(0.1),eps);
        assert.approximately(2.575829, Rates.ualpha(0.01),eps);
    });
});

/client/rates/ui/pages/experiment.js (the template)

import { Template } from 'meteor/templating';
import { Rates } from '/imports/math/rates.js';
import 'meteor/manuel:viewmodel';

Template.rates_experiment.viewmodel({
    alpha:0.01,
    rate: 0.5,
    precision: 0.01,
    interval:'constant',
    nIdeal : function(){
        var self = this;
        return Rates.nIdeal(self.rate, self.alpha, 'constant',self.precision);
    }
});

I also posted my issue on stackoverflow here : http://stackoverflow.com/questions/37187233/npm-import-with-meteor-conflict-between-test-and-production

Did anybody have the same issue with imports ?