Placeholder not working in select2

Question

I am working Select2 Select-box.

Problem

Placeholder is not showing in select2. It is always show the first option selected in the select2. It's automatically select first option i want to show the placeholder instead of it.

My Code:

Script:

<script type="text/javascript">
    $(document).ready(function () {
       var data = $('#test_skill').select2({
            placeholder: "Please select an skill",
            allowClear: true
       });
    });

// I have also tried this: This is also not working
    $('#test_skill').select2({
      placeholder: {
        id: '-1', // the value of the option
        text: 'Please select an skill'
      } 
    });
</script>

HTML:

<select class="skills_select2" required name="test_skill" id="test_skill">          
    <option value="1">TEST1</option>
    <option value="2">TEST2</option>
    <option value="3">TEST3</option>            
</select>

Answer 1

Just put <option></option> in select on first place:

$(document).ready(function() {
  $selectElement = $('#test_skill').select2({
    placeholder: "Please select an skill",
    allowClear: true
  });
});

.skills_select2 {
  width: 120px;
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/select2/4.0.3/js/select2.min.js"></script>
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/select2/4.0.3/css/select2.css" />
<select class="skills_select2" required name="test_skill" id="test_skill">   
    <option></option>
    <option value="1">TEST1</option>
    <option value="2">TEST2</option>
    <option value="3">TEST3</option>            
</select>