select2-rails misbehaving on browser-back (displaying twice)

Question

select2-rails gem seems to have problems with the browser-back function in my project:

Steps to recreate bug:

go to http://methoden-app.herokuapp.com/
click on any link
use back button of your browser

the select2-selects in the form will have doubled: image of bug

my code:

Gemfile:

ruby 2.3.1  
rails 5.0.0.1  
gem select2-rails 4.0.3

view:

<head>
  <script>
    $(document).ready(function() {
      $(".multi_select").select2({ theme: bootstrap", placeholder: "Bitte mindestens 1 auswählen"
      });
    });
  </script>
</head>

<%=form_tag( practices_path, method: "get", remote: true ) do %>
  <div class="form-group">
    <%=label_tag(:category_ids, "Kategorien:") %>
      <%=select_tag( 'category_ids', options_from_collection_for_select(@categories, "id", "name"), class: "multi_select", multiple: true, style: "width: 100%", autocomplete: 'off' ) %>
  </div>
      .
      .
      .
  <div class="form-group">
    <%= label_tag(:area_ids, "Räume:") %>
    <%= select_tag( 'area_ids', 
        options_from_collection_for_select(@areas, "id", "name"), 
        class: "multi_select", multiple: true, style: "width: 100%" ) %>
  </div>
  <div class="form-group row">
    <%=submit_tag( "Filter anwenden", class: "btn btn-primary" ) %>
      <%=link_to "Filter zurücksetzen", root_path, class: "btn btn-default", style: "float: right" %>
  </div>
  <% end %>

controller:

class PracticesController < ApplicationController  
  .
  .                                             
  .
  def index
    @categories = Category.all
    @areas = Area.all
    @practices = Practice.with_category(params[:category_ids])\
                         .with_participants(params[:participants])\
                         .with_min_duration(params[:min_duration])\
                         .with_max_duration(params[:max_duration])\
                         .with_age(params[:age])\
                         .with_areas(params[:area_ids])\
                         .paginate(:page => params[:page])
    respond_to do |format|
      format.html
      format.js
    end
  end
  .
  .
  .
end

What I tried:

chrome-pc, chrome-android and firefox-pc -> no difference
put select2 jquery-code in application.js/practices.coffee -> form is not using select2-styling
removing following snippet, but leaving the part between "{}" -> form not using select2-styling
```
$(document).ready(function() { ... });
```
add autocomplete: 'off' -> no difference
searching the web for 2 days
trying to write a test for the bug, put giving up due to lack of knowledge

My questions:

Any ideas on why this happens and what to do about it?

How can i use the browser-back function in my test for the bug? (I only know Minitest, no Rspec)

require 'test_helper'

class PracticesIndexTest < ActionDispatch::IntegrationTest


  test "select2 should work properly" do
    get practices_path
    assert_template 'practices/index'
    assert_select 'select.multi_select', count: 2
    get practice_path(id: 2)
  # something like 'javascript:history.back()' ?
    assert_select 'select.multi_select', count: 2
  end
end

I'm still pretty new to programming (coming straight from Michael Hartls rails tutorial into this project). So I hope you pros can help me ;) THX

select2-rails misbehaving on browser-back (displaying twice)

Steps to recreate bug:

my code:

What I tried:

My questions:

0 Answers0