Can't update to rails 4.1: Conflict with simple_form

Question

When updating from rails from 4.0 to 4.1, I stumbled in the following dependency problem:

Fetching additional metadata from https://rubygems.org/..
Resolving dependencies...
Bundler could not find compatible versions for gem "activemodel":
  In Gemfile:
    simple_form (>= 0) ruby depends on
      activemodel (< 4.1, >= 4.0.0) ruby

    rails (= 4.1.0) ruby depends on
      activemodel (4.1.0)

How can I install rails 4.1 with simple_form?

Answer 1

You need to use the github version, since the rubygems one don't seems to work. On your gemfile, update the simple_form to:

gem 'simple_form', github: 'plataformatec/simple_form'

Source: google groups in a language which I can't read