$controller is undefined for one controller during unit test

I have 2 controllers - main and vendor. main.controller successfully logs in my unit test, while vendor.controller gives me an undefined error with the exact same unit test.

unit test

describe('controllers', () => {
    let vm;

    beforeEach(angular.mock.module('thcmaps-ui'));
    beforeEach(inject(($controller) => {
        vm = $controller('MainController'); // This logs correctly but errors when changed to VendorController
        //vm = $controller('VendorController'); 
    }));

    it('should call stateManagerService when current name is main', () => {
        console.log(vm);
        expect(1).toEqual(1);
    });
});

I don't know if it's a routing issue or something completely different...

index.route.js

export function routerConfig($stateProvider, $urlRouterProvider) {
'ngInject';
$stateProvider
    //mobile
    .state('main', {
        url         : '/',
        templateUrl : 'app/main/main.html',
        controller  : 'MainController',
        controllerAs: 'main',
        resolve : {
            location : function(userDataService){
                return userDataService.getLocation()
                    .then(function(data){
                        return data;
                    });
            }
        }
    })
    .state('mobile', {
        url         : '/m/',
        templateUrl : 'app/main/main.html',
        controller  : 'MainController',
        controllerAs: 'main',
        resolve : {
            location : function(userDataService){
                return userDataService.getLocation()
                    .then(function(data){
                        return data;
                    });
            }
        }
    })
    .state('mobile.vendor', {
        url         : 'v/:slug',
        templateUrl : 'app/vendor/vendor.html',
        controller : 'VendorController',
        controllerAs : 'vendor',
        resolve : {
            data : function($stateParams, vendorDataService){
                return vendorDataService.getVendor($stateParams.slug)
                    .then((vendor) =>{
                        return vendor;
                    })
                    .catch(()=>{
                        //todo error handling
                        //console.log(error);
                    })
            },
            location : function(userDataService){
                return userDataService.getLocation()
                    .then(function(data){
                        return data;
                    });
            }
        }
    })
    //desktop
    .state('map.vendor', {
        url         : 'v/:slug',
        templateUrl : 'app/vendor/vendor.html',
        controller : 'VendorController',
        controllerAs : 'vendor',
        resolve : {
            data : function($stateParams, vendorDataService){
                return vendorDataService.getVendor($stateParams.slug)
                    .then((vendor) =>{
                        return vendor;
                    })
                    .catch(()=>{
                        //todo error handling
                        //console.log(error);
                    })
            },
            location : function(userDataService){
                return userDataService.getLocation()
                    .then(function(data){
                        return data;
                    });
            }
        }
    });


  $urlRouterProvider.otherwise('/');
}