After refactoring

errorize-test.js

```javascript
import errorize from '../../../utils/errorize';
import { module, test } from 'qunit';

module('Unit | Utility | errorize');

test('errorize', function(assert) {
  var errors = {
    responseJSON: {
      errors:[
        {
          code:100,
          title:'has already been taken',
          detail:'Email has already been taken',
          source:{
            pointer:'/data/attributes/email',
          },
        },
        {
          code:100,
          title:'is too short (minimum is 6 characters)',
          detail:'Password is too short (minimum is 6 characters)',
          source:{
            pointer:'/data/attributes/password',
          },
        },
     ],
    },
  };

  var expected = {
    email: [
      {message: 'Email has already been taken'},
    ],
    password: [
      {message: 'Password is too short (minimum is 6 characters)'},
    ],
  };

  let errorizeObject = errorize.create({errors});
  assert.deepEqual(errorizeObject.serialize(), expected, 'errorize should equal errors');
});
```

errorize.js

```javascript
import Ember from 'ember';

var errorize = Ember.Object.extend({
  init() {
    this._super();
    this.set('errorsList', {});
  },

  passedErrorObject() {
    return !Ember.isNone(this.get('errors'));
  },

  buildErrorObjectFor(error) {
    let field = this.getErrorObjectField(error);
    let message = this.getErrorObjectMessage(error);
    this.addOrCreateErrorForField(field, message);
  },

  getErrorObjectField(error) {
    // { source: { pointer:'/data/attributes/email' } }
    return (/\w+$/.exec(error.source.pointer))[0].camelize();
  },

  getErrorObjectMessage(error) {
    return error.detail;
  },

  addOrCreateErrorForField(field, message) {
    let fieldPath = 'errorsList.'+field;
    this.get(fieldPath) = this.get(fieldPath) || [];
    this.get(fieldPath).push({message});
  },

  serialize() {
    if (!this.passedErrorObject()) {
      return {};
    }
    this.get('errors.responseJSON.errors').forEach(error => this.buildErrorObjectFor(error));
    return this.get('errorsList');
  },
});

export default errorize;
```