Rails 5 app won't load JS from assets/javascripts folder

Question

As I understand it any js file in the assets/javascripts folder is loaded if /= require_tree is present in the application.js file. I can't get my JS code to work, however. I have put it in assets/javascripts/locations.js and it doesn't work. When I put it in a script tag in my application.html.erb file it worked perfectly on the other hand. Any ideas what I could be missing? Running Rails 5.2. The JS code is below.

locations.js

var locations = ["coordinatesStore"]
  .map(id => document.getElementById(id));

Array.prototype.forEach.call(
  document.querySelectorAll('.add-button'),
  (button, i) => {
    button.addEventListener('click', () => getLocation(i));
  }
);

function getLocation(i) {
  var location = locations[i];
  if (navigator.geolocation) {
    navigator.geolocation.getCurrentPosition(({ coords: { latitude, longitude }}) => {
      location.value = latitude + ", " + longitude;
    });
  } else { 
    location.value = "Geolocation is not supported by this browser.";
  }
}

I have this tag in my application.html.erb

<%= javascript_include_tag 'application', 'data-turbolinks-track': 'reload' %>

Answer 1

Where is <%= javascript_include_tag 'application', 'data-turbolinks-track': 'reload' %> in your application.html.erb ?

Try putting it at the end of your body tag, at least after the <%= yield %>