Workaround to have a datepicker with mask

datepicker-mask.directive.js

//Immediately Invoked Function Expression (IIFE)
(function() {
  'use strict';

  angular
    .module('app')
    .directive('datepickerMask', datepickerMask);

  function datepickerMask() {
    var directive = {
      templateUrl: 'views/datepicker-mask.html',
      scope: {
        inputDate: '=',
        inputName: '=',
        minDate: '=?',
        maxDate: '=?'
        //inputWid: '=?'
      },
      controller: datePickerMaskController,
      controllerAs: 'vm',
      bindToController: true
    };
    return directive;
  }

  datePickerMaskController.$inject = ['moment', '$log'];
  function datePickerMaskController(moment, $log) {
    var vm = this; // ViewModel

    vm.dt = {
      opened: false
    };
    vm.changeInput = changeInput;
    vm.changeDP = changeDP;
    vm.openDt = openDt;

    changeDP();

    function changeInput() {
      if (typeof vm.temp !== 'undefined') {
        var day = vm.temp.substring(0, 2);
        var month = vm.temp.substring(2, 4) - 1;
        var year = vm.temp.substring(4, 8);

        var t = moment({
          year: year,
          month: month,
          day: day
        });

        //$log.debug('moment: ', t);

        if (t.isValid()) {
          vm.inputDate = t.toDate();
        } else {
          vm.temp = null;
          vm.inputDate = null;
        }
      }
    }

    function changeDP() {
      if (!vm.inputDate) {
        vm.temp = null
      } else {
        var t = moment(vm.inputDate);

        if (t.isValid()) {
          vm.temp = t.format('DD/MM/YYYY');
        } else {
          vm.temp = null;
        }
      }
    }

    function openDt($event) {
      $event.preventDefault();
      $event.stopPropagation();

      vm.dt.opened = !vm.dt.opened;
    }
  }
})();

datepicker-mask.jade

.input-group
  input.form-control(type="text" name="vm.inputName" ng-model="vm.temp" ui-mask="99/99/9999" ng-change="vm.changeInput()")

  .dp-hackyhack
    input.form-control(style="opacity: 0; width: 0; height: 0; padding:0; margin: 0;" ng-change="vm.changeDP()"
      type="text" name="vm.inputName" datepicker-popup="dd/MM/yyyy" placeholder="dd/mm/aaaa" ng-model="vm.inputDate"
      is-open="vm.dt.opened" min-date="vm.minDate" max-date="vm.maxDate" close-text="Fechar" clear-text="Limpar" current-text="Hoje")
  a.btn.btn-default.input-group-btn(type="button" ng-click="vm.openDt($event)")
    i.glyphicon.glyphicon-calendar
    | Escolher data

style.css

.dp-hackyhack {
  position: relative;
}

.dp-hackyhack .dropdown-menu {
  left: auto !important;
  right: -150px;
  top: 40px !important;
}