Angular-styleguide: .component helper

With the release of Angular 1.5 we can use the .component() shortcut to create component directives.
Do you have any suggestions in the way to use it ?

I have been a big follower of your styleguide for some time and here is how I usually write them.

Small ones, without the need of a controller, I like to write the template inside the same file as the return value of a hoisted function

(function() {
  'use strict';

  var componentConfig = {
    template: generateTemplate(),
    bindings: {
      kpiVal: '=',
      kpiLabel: '=',
    },
  };

  angular
    .module('app.utils.kpi')
    .component('sfKpi', componentConfig);

  //
  function generateTemplate() {
    return [
      '<div class="sf_kpi">',
      '  <div class="sf_kpi__number">{{ $ctrl.kpiVal }}</div>',
      '  <div class="sf_kpi__label">{{ $ctrl.kpiLabel }}</div>',
      '</div>',
    ].join('');
  }
}());

For more advanced ones I like to put the template in a separate file and use 'templateUrl' property.

(function() {
  'use strict';

  var componentConfig = {
    templateUrl: 'components/active-places/active-places.widget.html',
    controller: controller,
  };

  angular
    .module('app.widget.activeplaces')
    .component('activePlaces', componentConfig);

  /* @ngInject */
  function controller($log, activityService) {
    var vm = this;

    vm.activities = [];
    vm.isLoading = true;

    vm.doFunnyStuff = doFunnyStuff;

    activate();

    function activate() {
      $log.info('👊 activating activePlaces component');

      activityService.getActivites()
        .then(fetchData)
        .catch(handleError)
        .finally(stopLoader);

      //
      function fetchData(activities) {
        vm.activities = activities;
        $log.log('👓 activePlaces activities fetched: ', activities);
      }
      function handleError(err){
        $log.error('💥 problem fetching activePlaces data', err);
      }
      function stopLoader() {
        vm.isLoading = false;
        $log.info('💪 activePlaces component started');
      }
    }

    // methods
    function doFunnyStuff() {
      vm.activities.push('yolo');
    }

  }

}());

I am also curious about your opinion about the $onInit hook and how do you think components should be tested.

Thanks