Load test deps in Ruby core CI.

Author: simi

.github/workflows/ruby-core.yml

@@ -61,6 +61,10 @@ jobs:
           ruby tool/sync_default_gems.rb rubygems
           mv spec/bundler/support/bundle spec/bin/bundle # TODO: fix `sync_default_gems.rb` script so we don't need to vendor the ruby-core binstub ourselves
         working-directory: ruby/ruby
+      - name: Install test dependencies
+        run: make install-for-test-bundled-gems
+        working-directory: ruby/ruby
+        if: matrix.target == 'Rubygems'
       - name: Test RubyGems
         run: make -s test-all TESTS="--no-retry -j$((1 + $(nproc)))"
         working-directory: ruby/ruby

test/rubygems/helper.rb

@@ -17,6 +17,7 @@
 require "tmpdir"
 require "rubygems/vendor/uri/lib/uri"
 require "zlib"
+gem "compact_index", "~> 0.15.0"
 require "compact_index"
 require_relative "mock_gem_ui"