How Does It Work

The rbenv-binstubs plugin works by enhancing rbenv-which to use the files generated by the bundle --binstubs command if they exist. The bundle --binstubs command creates files that are configured to use the version of the command specified in the Gemfile rather than the default (highest version installed). The shims generated by rbenv use rbenv-exec which uses rbenv-which to determine which file to execute.

Using this plugin after you have run bundle --binstubs has the same effect as either using bin/COMMAND or bundle exec COMMAND to run your commands. Ie it will execute the binaries associated the gem versions specified in the Gemfile.

The plugin also checks if you used a non standard binstub directory, and if so checks there rather than the local bin directory.

Without running bundle --binstubs

If you have not run bundle --binstubs then there will be no bin stubs for this plugin to use, and the default commands will be run instead. Note the binstubs setting is sticky, ie it is saved in .bundle/config and used when you next run bundle.

Without this plugin

Without this plugin you will need to prefix your commands with bundle exec or bin/ (if you have run bundle --binstubs). If you do not do this then the highest available version will be executed, irrespective of what is specified in your Gemfile.