I was following the Getting Started part of the Rails Guides and created the welcome controller as per the tutorial. I started the server and opened http://localhost:3000/ and instead of the <h1>Hello, Rails!</h1> it was supposed to see, I got the error Did not recognize your adapter specification.
The error block was just some HTML from the application.html.erb file, this was the offending line:
<%= javascript_include_tag "application", "data-turbolinks-track" => true %>
If I remove this line from the file, it works as expected. I googled the error and it I saw it could have something to do with the json or coffeescript gems. I have those gems installed and up to date, along with the rails and turbolinks gems, and as far I can tell they all seem to be working fine.
This is not essential, but I'd like to have turbolinks working in my Rails apps. It also feels bad to be clueless about what is wrong. How can I solve this?
I just ran into this problem again and googling again I found this question, with a similar problem.
I downgraded the multi_json gem to version 1.7.8 in the bundler, as mentioned there, and I stopped getting the error. I have yet to see if it will work in Heroku, but it's apparently solved the issue in development. If it doesn't, I'll update this answer.