Migrating an AngularJS factory to TypeScript

Question

I am in the process of preparing to migrate an AngularJS app to Angular. I am currently looking at converting the JS code to TS. I haven't had any issues with components and services but factories. I can't figure out how to convert factories to use TypeScript.

Here's an example:

(function() {
    'use strict';

    angular.module('MyApp')
      .factory('Fruit', Fruit);

    /** @ngInject */
    function Fruit() {

      var Fruit = function(dto) {
        // dto properties
        this.id = "";
        this.name = "";
        this.type = "Orange";
        this.color = "#000000";

        //--------------
        // Create from API response DTO
        if (dto) {
          this.id = dto.id;
          this.name = dto.data.name;
          this.type = dto.data.type;
          this.color = dto.data.color;
        }
      };

      return Fruit;
    }
})();

I've tried this but doesn't work. I get dto -> dtoProvider not found.

(function() {
    'use strict';

    angular.module('MyApp')
      .factory('Fruit', class Fruit {

        // dto properties
        public id = "";
        public name = "";
        public type = "Orange";
        public color = "#000000";
        constructor (private dto: any) {
          // Create from API response DTO
          if (dto) {
            this.id = dto.id;
            this.name = dto.data.name;
            this.type = dto.data.type;
            this.color = dto.data.color;
          }
        }
      })
    })();

P.S. i do not have the ability to import/export classes yet.

Answer 1

Put the Fruit function inside the class constructor function and return it:

class Fruit {
    constructor () {
        function Fruit(dto) {
            // dto properties
            this.id = "";
            this.name = "";
            this.type = "Orange";
            this.color = "#000000";
            //--------------
            // Create from API response DTO
            if (dto) {
                this.id = dto.id;
                this.name = dto.data.name;
                this.type = dto.data.type;
                this.color = dto.data.color;
            };
        }
        return Fruit;
    }
}

angular.module("myApp",[])
.factory("Fruit", Fruit);
.run(function(Fruit) {
  var x = new Fruit();
  console.log(x);
})

The DEMO on PLNKR