input time checking if empty jquery

Why this code is not working ? Even if I fill the input time is triggering alert(’empty’)

<label for="">New ETA:</label>
   <input type="time" class="neweta">
   <input type="button" onclick="newetasave(this)" value="save"></br>

function newetasave(t){
 var tr = $(t).closest('tr').prev()
 var neweta = $(t).prev('input').val()

 if ($(neweta).val("")) {
   alert('empty')

 }else {
   alert('not empty')
// $(tr).find('.eta').text(neweta)
 }
}

>Solution :

Your code is incomplete, i strongly recommend going through the jQuery documentation first.

Your code needs to be something like this:

function newetasave(t){
 var tr = $(t).closest('tr').prev();
 var neweta = $(t).prev('input'); //Now its a jquery object

 if ($(neweta).val().length == 0) {
   alert('empty');

 }else {
   alert('not empty')
// $(tr).find('.eta').text(neweta)
 }
}

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<label for="">New ETA:</label>
   <input type="time" class="neweta">
   <input type="button" onclick="newetasave(this)" value="save"></br>