Default values are not correctly set for inputs with several occurrences on content create

[alansemenov]

This content type has a TextLine input with a default value and min 3 occurrences (which means they should be created automatically).

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<content-type>
  <display-name>Test</display-name>
  <super-type>base:structured</super-type>
  <form>
    <input name="field1" type="TextLine">
      <label>Field 1</label>
      <occurrences minimum="3" maximum="3"/>
      <default>Default text</default>
    </input>
  </form>
</content-type>

In Content Studio it's rendered correctly (correct number of fields with the default value):

But the content is created with wrong data (only one occurrence of field1):

  "data": {
    "field1": "Default text"
  },

After first save data becomes correct:

  "data": {
    "field1": [
      "Default text",
      "Default text",
      "Default text"
    ]
  },

This is also a problem with container inputs (like item-sets) that have several occurrences.

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<content-type>
  <display-name>ItemSet</display-name>
  <super-type>base:structured</super-type>
  <form>
    <input name="field1" type="TextLine">
      <label>Field 1</label>
      <occurrences minimum="1" maximum="1"/>
      <default>Default text</default>
    </input>
    <item-set name="field2">
      <label>Field 2</label>
      <items>
        <input name="label" type="TextLine">
          <label>Label</label>
          <occurrences minimum="1" maximum="1"/>
          <default>Default text</default>
        </input>
      </items>
      <occurrences minimum="3" maximum="3"/>
    </item-set>
  </form>
</content-type>

Content Studio:

Wrong data on create (only one occurrence of field2):

  "data": {
    "field1": "Default text",
    "field2": {
      "label": "Default text"
    }
  },

Correct data after save:

  "data": {
    "field1": "Default text",
    "field2": [
      {
        "label": "Default text"
      },
      {
        "label": "Default text"
      },
      {
        "label": "Default text"
      }
    ]
  },