Bundix can't handle Gemfile with the ruby version specified there about rails-nix HOT 7 CLOSED

It seems to build if the versions match? Nix's default Ruby version is 2.7.5. If I set ruby "2.7.5" in the Gemfile, run bundix -l and then nix-build it doesn't complain.

from rails-nix.

Likewise with ruby "3.0.3" in the Gemfile, running bundix -l, then setting ruby = pkgs.ruby_3_0 in default.nix... it builds successfully and the app runs with 3.0.3 🎉

from rails-nix.

Aha... but it breaks when adding new gems to the Gemfile. Ok, that seems like a bundix bug.

from rails-nix.

Yeah - probably not hard to fix.

from rails-nix.

Hmmm okay, I've had a bit more success by passing the ruby package to bundix. This works:

1. Add a new gem
2. Install it locally with bundle install
3. run bundix -l --ruby ruby_3_0 (referencing the Ruby nix package name)

from rails-nix.

I have this exact issue right now, I have a gemfile like this:

source 'https://rubygems.org'

# security patch pins min versions
gem 'aws-sdk-s3'
gem 'loofah', '>= 2.2.3'
gem 'rack', '>= 2.0.6'

ruby '2.7.1'

And I run bundix like this:

nix-shell -p bundix --run "bundix --init --ruby=ruby_2_7"

And I got error like this:

[nix-shell:~/demo]$ rails
Traceback (most recent call last):
        3: from /nix/store/55rlx3hhr0l4z75qjf8dw40cya6dqjz7-lbh-income-api-bundler-env/bin/rails:19:in `<main>'
        2: from /nix/store/xvaflscg5fh6391lc8dfyrx899iq8frg-bundler-2.3.6/lib/ruby/gems/2.7.0/gems/bundler-2.3.6/lib/bundler.rb:145:in `setup'
        1: from /nix/store/xvaflscg5fh6391lc8dfyrx899iq8frg-bundler-2.3.6/lib/ruby/gems/2.7.0/gems/bundler-2.3.6/lib/bundler/definition.rb:401:in `validate_runtime!'
/nix/store/xvaflscg5fh6391lc8dfyrx899iq8frg-bundler-2.3.6/lib/ruby/gems/2.7.0/gems/bundler-2.3.6/lib/bundler/definition.rb:426:in `validate_ruby!': Your Ruby version is 2.7.5, but your Gemfile specified 2.7.1 (Bundler::RubyVersionMismatch)

How can I fix this version error?

from rails-nix.

For our use case, we can probably ignore this by assuming that bundix is going to be run from a Nix environment defined by an app spec. The spec will be generated by a tool that detects the correct Ruby version from Gemfile and/or .ruby-version.

from rails-nix.