When `gem uninstall <gem> --install-dir <dir>` is run, if the version
removed had a plugin, and that same version happened to also be
installed globally, then the plugin stub would fail to be removed.
4e2fa0be77
This class handles all logic to handle the list of specifications, given
a set of GEM_PATH directories. Makes `Gem::Specification` has less
responsibilities and will help with fixing some bugs next.
df280dbbed