To work on Bundler, you'll probably want to do a couple of things:
-
Fork the Rubygems repo, and clone the fork onto your machine. (Follow this tutorial for instructions on forking a repo.)
-
Install
graphviz
package using your package manager:$ sudo apt-get install graphviz -y
And for OS X (with brew installed):
$ brew install graphviz
-
Install Bundler's development dependencies:
$ bin/rake spec:deps
-
Run the test suite, to make sure things are working:
$ bin/rake spec
-
Optionally, you can run the test suite in parallel:
$ bin/parallel_rspec
-
Set up a shell alias to run Bundler from your clone, e.g. a Bash alias (follow these instructions for adding aliases to your
~/.bashrc
profile):$ alias dbundle='/path/to/bundler/repo/bin/bundle'
To dive into the code with Pry: RUBYOPT=-rpry dbundle
to require pry and then run commands.
For background context: you can manipulate environment variables in Ruby to control the Ruby interpreter's behavior. Ruby uses the RUBYOPT
environment variable to specify options to launch Ruby with.
The arguments of RUBYOPT
are applied as if you had typed them as flags after ruby
. The -r
flag means 'require'. So saying -rpry
means require 'pry'
. To illustrate, ruby -rpry /path/to/bundle
is the same as RUBYOPT=-rpry ruby /path/to/bundle
.
So, RUBYOPT=-rpry dbundle
is saying "require pry and require this path to Bundler", which means that you will start your development environment with pry
and your local bundler.
Why is this necessary? Why isn't require 'pry'; binding.pry
enough?
The reason for combining RUBYOPT
with dbundle
is because Bundler takes over what gems are available. If you have pry
installed on your machine but not included in the Gemfile, Bundler itself will remove pry
from the list of gems you can require. Setting RUBYOPT=-rpry
is a way to require pry
before Bundler takes over and removes it from the list of gems that can be required. That way, later, you can take advantage of binding.pry
and have it work.
Unfortunately, if you waited until the point of binding.pry
to require 'pry'
, it would fail anytime pry
is not in the Gemfile.