Set `default-directory` to the project's root

[asok]

Have you ever thought about running the bundler from a project's root? Maybe by using locate-dominating-file or projectile.
I'm asking because now I work on a project which has something like that in Gemfile:

require './lib/gemfile_helpers'

And I'm forces to run bundle from the root dir of the project.

[asok]

As a workaround I did something like this:

  (defun asok/bundle--around (fun &rest args)
    "Run FUN from the project root."
    (projectile-with-default-dir (projectile-project-root)
      (apply fun args)))

  (advice-add 'bundle-command :around #'asok/bundle--around)

But I think it could be useful for bundler.el to do this by its own.