[rubygems/rubygems] Load "bundler/setup" in lib/rubygems.rb

Ruby interpreter loads some special gems at startup: did_you_mean,
error_highlight, and syntax_suggest. These gems are loaded before
`bundler/setup` is loaded by `RUBYOPT=-rbundler/setup`.
So, the versions of the gems are not controllable by Gemfile.

This change will `require "bundler/setup"` in rubygems.rb (i.e., before
the special gems are loaded). Now `bundle exec` sets an environment
variable `BUNDLER_SETUP`, and rubygems requires the variable if defined.

See also: https://bugs.ruby-lang.org/issues/19089

https://github.com/rubygems/rubygems/commit/963cb65a2d

1 files changed, 7 insertions, 0 deletions

diff --git a/spec/bundler/bundler/shared_helpers_spec.rb b/spec/bundler/bundler/shared_helpers_spec.rb
index 68a24be31c..569d6ed9cd 100644
--- a/spec/bundler/bundler/shared_helpers_spec.rb
+++ b/spec/bundler/bundler/shared_helpers_spec.rb
@@ -246,6 +246,13 @@ RSpec.describe Bundler::SharedHelpers do
       end
     end
 
+    shared_examples_for "ENV['BUNDLER_SETUP'] gets set correctly" do
+      it "ensures bundler/setup is set in ENV['BUNDLE_SETUP']" do
+        subject.set_bundle_environment
+        expect(ENV["BUNDLER_SETUP"]).to eq("#{source_lib_dir}/bundler/setup")
+      end
+    end
+
     shared_examples_for "ENV['RUBYLIB'] gets set correctly" do
       let(:ruby_lib_path) { "stubbed_ruby_lib_dir" }