bundler inline fails when BUNDLE_BIN is set (default in docker)

[robuye]

Hi there,

I'm trying to use bundler/inline feature to dockerize some scripts that require gems to be installed. I was able to reproduce the problem locally, it's doesn't appear to be docker specific issue.

Steps to reproduce:

Create example script in /tmp/inline.rb:

require 'bundler/inline'

gemfile(true) do
  source 'https://rubygems.org'

  gem 'aws-sdk'
end

Run the script in official docker container:

docker run --rm -v /tmp/inline.rb:/inline.rb -it ruby:2.4 ruby /inline.rb

Result:

Fetching gem metadata from https://rubygems.org/............
Fetching version metadata from https://rubygems.org/.
Resolving dependencies...
Fetching aws-sigv4 1.0.0
Installing aws-sigv4 1.0.0
Fetching jmespath 1.3.1
Installing jmespath 1.3.1
Using bundler 1.15.1
/usr/local/lib/ruby/gems/2.4.0/gems/bundler-1.15.1/lib/bundler/installer/parallel_installer.rb:142:in `handle_error': ArgumentError: different prefix: "" and "/usr/local/bundle/bin" (Bundler::InstallError)
An error occurred while installing aws-sigv4 (1.0.0), and Bundler cannot continue.
Make sure that `gem install aws-sigv4 -v '1.0.0'` succeeds before bundling.

In Gemfile:
  aws-sdk was resolved to 2.10.9, which depends on
    aws-sdk-resources was resolved to 2.10.9, which depends on
      aws-sdk-core was resolved to 2.10.9, which depends on
        aws-sigv4
        from /usr/local/lib/ruby/gems/2.4.0/gems/bundler-1.15.1/lib/bundler/installer/parallel_installer.rb:104:in `call'
        from /usr/local/lib/ruby/gems/2.4.0/gems/bundler-1.15.1/lib/bundler/installer/parallel_installer.rb:77:in `call'
        from /usr/local/lib/ruby/gems/2.4.0/gems/bundler-1.15.1/lib/bundler/installer.rb:199:in `install_in_parallel'
        from /usr/local/lib/ruby/gems/2.4.0/gems/bundler-1.15.1/lib/bundler/installer.rb:166:in `install'
        from /usr/local/lib/ruby/gems/2.4.0/gems/bundler-1.15.1/lib/bundler/installer.rb:80:in `run'
        from /usr/local/lib/ruby/gems/2.4.0/gems/bundler-1.15.1/lib/bundler/installer.rb:24:in `install'
        from /usr/local/lib/ruby/gems/2.4.0/gems/bundler-1.15.1/lib/bundler/inline.rb:63:in `gemfile'

It works when BUNDLE_BIN is unset or false:

docker run -e BUNDLE_BIN=false --rm -v /tmp/inline.rb:/inline.rb -it ruby:2.4 ruby /inline.rb

Fetching gem metadata from https://rubygems.org/............
Fetching version metadata from https://rubygems.org/.
Resolving dependencies...
Fetching aws-sigv4 1.0.0
Installing aws-sigv4 1.0.0
Fetching jmespath 1.3.1
Installing jmespath 1.3.1
Using bundler 1.15.1
Fetching aws-sdk-core 2.10.9
Installing aws-sdk-core 2.10.9
Fetching aws-sdk-resources 2.10.9
Installing aws-sdk-resources 2.10.9
Fetching aws-sdk 2.10.9
Installing aws-sdk 2.10.9

Output of bundle env from docker container:

bundle env
## Environment

Bundler   1.15.1
Rubygems  2.6.12
Ruby      2.4.1p111 (2017-03-22 revision 58053) [x86_64-linux]
GEM_HOME  /usr/local/bundle
GEM_PATH  
Git       2.1.4
Platform  x86_64-linux

## Bundler settings

silence_root_warning
  Set via BUNDLE_SILENCE_ROOT_WARNING: "1"
app_config
  Set via BUNDLE_APP_CONFIG: "/usr/local/bundle"
bin
  Set via BUNDLE_BIN: "/usr/local/bundle/bin"
path
  Set via BUNDLE_PATH: "/usr/local/bundle"

This is from the official, up to date, ruby docker image. I'm getting exactly same error on my local environment by running BUNDLE_BIN=/tmp ruby /tmp/inline.rb.

The workaround I'm using now is to simply update the script with ENV['BUNDLE_BIN'] = nil at the very top. That works, but it feels to be a bug so I'm creating an issue.

Thanks so much for doing awesome work on bundler and taking time to look into this problem!

[segiddins]

Thanks for the 💯 issue! #5848 should fix this.

[robuye]

Thanks so much @segiddins! 💯 👍 😻