Mocha and Chai-as-promised time out

Here is a test I believe should work.

var chai = require( 'chai' ),
    chaiAsPromised = require( 'chai-as-promised' ),
    assert = require( 'chai' ).assert,
    should = require( 'chai' ).should(),
    saveImage = require( 'helpers/save-image' ),
    Mocha = require( 'mocha' ),
    path = require( 'path' ),
    getUser = require( 'helpers/get-user' )

describe( 'GetUser', function () {

    describe( "getUser( token )", function() {

        it( "should return a user's ID when given token", function() {
            this.timeout( 4000 )

            var token = "LONG-STRING"

            return getUser( token ).should.eventually.include( 'ANOTHER-STRING' )
        })

    })

})

Here is the function

var User = require( '../models/userModel' ),
    Q = require( 'q' )

module.exports = function getUser ( token ) {
    return Q.Promise( function ( resolve, reject, notify ) {

        User.findOne( { token: token } ).exec()
        .then( function ( data ) {
            if ( !data )
                reject( new Error( "There was a problem getting the user. No user with that token." ) )

            resolve( data.id )
        }, function ( error ) {
            reject( new Error( error ) )
        })
    })
}

When I call this function in my app, and use the node-theseus debugger, I see that the function on line 8 fires (.then( function ( data ) { ...).

But when I run Mocha with the debugger I see that function, or any other, doesn't fire. I only see a call fire on line 4 and 5. The test is being done with the exact same LONG-STRING as a token argument that I'm using on my app front end.

Why is there a difference in how Mocha and node see my app and how can I make this test work?