Update Rails to a Specific Version

Update rails to a specific version

gem install rails --version=3.2.3

Or use bundler. Write in Gemfile:

gem 'rails', '3.2.3'

and execute in rails root directory

bundle install

How do I upgrade Rails?

If you are using RVM then you should create a seperate gemset first like:

rvm gemset create whateverName

in this example I will install rails 4

rvm install 2.0.0

rvm list  

rvm 2.0.0 

^^^^(you may need to copy and paste the version number exactly here as it was displayed in rvm list)

rvm gemset create rails4

rvm gemset use rails4

add the following to your gemfile for existing apps

gem 'rails', '4.0.0'

then run

bundle update rails

or do following to just install the gem

gem install rails --version=4.0

UPDATE

If you havne't installed Xcode 4.5 CLI tools then you will need to

Preferences > Downloads > Components

DMG

https://developer.apple.com/downloads

you may then also need to use homebrew to update gcc

brew install apple-gcc42

the following link has all the information you will need:

https://thoughtbot.com/blog/the-hitchhikers-guide-to-riding-a-mountain-lion

how update Rails ruby minor version

The specifier ~> has a special meaning, best shown by example. ~> 3.0 is identical to >= 3.0 and < 3.1. So all minor patches are included. See https://bundler.io/gemfile.html.

No need to change your Gemfile just install the gems in the newly installed Ruby version.

How do I upgrade rspec to a specific version in my Rails project?

Upgrade all gems that are mentioned and might collide with their required RSpec-version. The output tells you, that guard-rspec collides with a newer RSpec-version. Try with:

bundle update rspec rspec-rails guard-rspec

If then there is another error with new Gems, try adding those to the command, too. Transitive dependencies, that are not listed in your Gemfile are generally not required to list (rspec-mocks etc.).

Summary: Try upgrading all related offending Gems at once.

Also, as Les said, you are not supposed to update Gemfile.lock manually (except in case of Merge Conflicts), but only through bundle update [GEMNAME].

Deleting Gemfile.lock is a last resort, as you will lose your current, maybe well-functioning, dependency situation and upgrade all Gems at once to their newest version, as specified in the Gemfile.

ROR - How to update a rubygem to a particular version?

In your Gemfile specify the gem version. For example:

gem "foo", "= 1.0.0"

then run bundle update foo

How to switch to an older version of rails

First, uninstall the version of Rails you have:

gem uninstall rails

Next, install the version of Rails you want, like so:

gem install rails -v 3.1.12

There are a few ways to have both "installed" at the same time. As Joe Frambach suggested, you could install Rails 4 in a VM. You could also install RVM - the Ruby enVironment Manager - and use separate gemsets to keep the two versions of Rails apart. But if you are just learning you may not want to bother with this.

Edit: @Shadwell's answer got it right, although it could use some expansion, which I'll do here:

> rvm gemset create rails3
> rvm gemset use rails3
> gem install rails -v 3.1.12
> rails my_new_app

Specifying rails version to use when creating a new application

I found here an undocumented option to create a new application using an older version of Rails.

rails _2.1.0_ new myapp 

---

Related Topics