methods,undefined , Repeating Error: undefined method `start_with?' for nil:NilClass

Repeating Error: undefined method `start_with?' for nil:NilClass


Tag: methods,undefined

I've gotten this weird error message that keeps me from working on my application.

undefined method `start_with?' for nil:NilClass

with line 5 highlighted in my app/views/layouts/application.html.erb file:

<%= stylesheet_link_tag    'application', media: 'all', 'data-turbolinks-track' => true %>

The error seems to come out of nowhere. The first time I got it I had attempted to load CarrierWave. I got through ReadMe but it didn't work so I tried to back out of the installation.

When I comment out this line the app loads but with no bootstrap formatting at all. I initially focused my search with CarrierWave, deleted and re-installed the gem, but was unsuccessful and found nothing really pointing me in the right direction. I spent days on this. Finally, I reached out to a mentor who pulled my code down from github and found no errors. The app worked fine for him. I pulled down a previous, known working commit, and it worked for me as well. So, although not solved I could continue working on my app (having to re-do some work). Now, the problem has reappeared while working on my app. Not CarrierWave this time, just normal editing. Without warning the application just stopped loading but with the same start_with? error message on my app/views/layouts/application.html.erb file.

I've spent a considerable amount of time searching for answers and a permanent fix on Stackoverflow.

Solutions that seemed to work for others, but HAVE NOT worked for me are: 1. Remove //= require_tree . from application.js, and 2. Downloading and installing node.js

Some posts support the thought that the idea that the issue is local and would only show up in dev, not prod. I'm only working in dev at the moment. While there's a lot of other info, I've struggled with this for days now and feel that every possible solution gets me further down a rabbit hole that is completely foreign to me. I am a newbie...about 3 months into my knowledge on Ruby. I'm really not even sure what code to add here because I can't seem to isolate the issue. I only know that formatting seems to be affected when I comment out line 5 (as above).

Trust me when I say I've searched quite a bit. I'm very hard headed, but optimistic I can find an answer if given the time but I'm stumped here and just want to move on with learning to create with Ruby/Rails.

My gem file is below. Perhaps I'm missing something very obvious.

ruby '2.2.0'

source ''

group :production do
  gem 'pg'
  gem 'rails_12factor'

gem 'font-awesome-sass'
gem 'bootstrap-sass'
gem 'simple_form'

gem 'devise'

gem 'seed_dump'

gem 'rails', '4.2.0'
group :development do
  gem 'sqlite3'
gem 'sass-rails', '~> 5.0'
gem 'uglifier', '>= 1.3.0'
gem 'coffee-rails', '~> 4.1.0'
gem 'jquery-rails'
gem 'turbolinks'
gem 'jbuilder', '~> 2.0'
gem 'sdoc', '~> 0.4.0', group: :doc

group :development, :test do
 gem 'byebug'
 gem 'web-console', '~> 2.0'
 gem 'spring'


//= require jquery
//= require jquery_ujs
//= require turbolinks
//= require_tree .
//= require bootstrap-sprockets

The only other info I can provide is that I've scaffolded my resources and used devise to create my User model.

Thanks. I'm in your debt if you can help me solve this. I am new, but I want to learn.


I came across this same issue myself maybe my solution will help you out. Check your /app/assets/stylesheets/application.scss file for "bootstrap-spockets". Commenting this out solved it for me.


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