How to spy on a property that is not exported - node.js

Question

I have a module "sitescollection" like this:
var site = require('./site'); // <- this should be stubbed
var sitesCollection = function(spec) {
var that = {};
that.sites = {};
that.findOrCreateById = function(id) {
if (typeof(that.sites[id]) == "undefined") {
that.sites[id] = site({id: id}); // <- its used here
}
return that.sites[id];
};
return that;
};
module.exports = sitesCollection;
so within sitescollection, site is a module that is not exported. But inside the code, i use it. Now i'm writing jasmine specs for #findOrCreateById().
I want to spec my the findOrCreateBy() function. But i want to stub the site() function, because the spec should be independent from the implementation. Where do i have to create the spyed method on?
var sitescollection = require('../../lib/sitescollection');
describe("#findOrCreateById", function() {
it("should return the site", function() {
var sites = sitescollection();
mysite = { id: "bla" };
// Here i want to stub the site() method inside the sitescollection module.
// spyOn(???,"site").andRetur(mysite);
expect(sites.findOrCreateById(mysite.id)).toEqual(mysite);
});
});

Answer 1

You can achieve this using https: //github.com/thlorenz/proxyquire
var proxyquire = require('proxyquire');
describe("#findOrCreateById", function() {
it("should return the site", function() {
// the path '../../lib/sitescollection' is relative to this test file
var sitesCollection = proxyquire('../../lib/sitescollection', {
// the path './site' is relative to sitescollection, it basically
// should be an exact match for the path passed to require in the
// file you want to test
'./site': function() {
console.log('fake version of "./site" is called');
}
});
// now call your sitesCollection, which is using your fake './site'
var sites = sitesCollection();
var mysite = {
id: "bla"
};
expect(sites.findOrCreateById(mysite.id)).toEqual(mysite);
});
});