Array showing only first item (but not in the playground)

[SimoneMSR]

Issue type

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[x] Bug report

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Current behavior

When having a json object with one property being an array,

1. only the first item is showed. Differently from issue array showing only first item #195 , no console errors are showed. Moreover,
2. after the view is rendered, the ngModel 'data' property is changed so that the array (now) has just one element!

If using the same data, schema and form settings in the playground, everything works.

Expected behavior

When having a json object with one property being an array,

1. all array items should be visible
2. the ngModel array property should not be updated to an array of length 1!

IMPORTANT: How can we reproduce your problem?

schema:

{
    'type': 'object',
    'properties': {
      'brokers': { 
        'type': 'array',
        'items' : {
          'type' : 'object',
          'properties' : {
            "broker": { 'type': 'string' }
          }
        }
       }
    }
  };

form

[
    {
      type: "tabs",
      tabs: [
      {
         title: "Brokers",
          type: "array",
          startEmpty: false,
          items : [
            "brokers[].broker"
          ]
        }
      ]
    }
  ];

{
"brokers": [
    {
      "broker": "Coincheck",
    },
    {
      "broker": "Bitflyer",
    }
  ]
}

Environment

OS name & version: Windows 10
Browser name & version: Chrome 65.0.3325.181 (official Build) (64 bit)
Angular version: 5.2.4
Angular JSON Schema Form version(s): 0.7.0-alpha.1
Other relevant software or packages:
Angular/flex-layout : 2.0.0-beta.12
boostrap : 4.0.0