Add Show The Bundler Location Of An Installed Gem as a Ruby TIL

ruby/show-the-bundler-location-of-an-installed-gem.md

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+# Show The Bundler Location Of An Installed Gem
+
+When you run `bundle install` with a project, it is going to install all the
+gems specified by your project in a vendored location relative to the location
+of your Ruby version install.
+
+If you want to find the location of a specific gem, you can ask bundler with
+`bundle show <gem-name>`.
+
+Here I ask where the `rspec` gem is.
+
+```bash
+$ bundle show rspec
+/Users/jbranchaud/.asdf/installs/ruby/3.1.3/lib/ruby/gems/3.1.0/gems/rspec-3.12.0
+```
+
+I could `cd` into that directory to have a look around at the source. That's a
+great way to learn more about how our dependencies work.
+
+I could even inject some debugging statements (e.g. `binding.irb`) which the
+program using these gems will break on. Not often, but sometimes you need to
+dig in this deep to understand what is causing a tricky bug or why code isn't
+behaving like you'd hoped. Just remember to remove those statements when you're
+done.