[rubygems/rubygems] Restore the old .gemrc example for compatible tests

https://github.com/rubygems/rubygems/commit/c45d65a06d

spec/bundler/bundler/friendly_errors_spec.rb

@@ -6,6 +6,31 @@ require "cgi"
 
 RSpec.describe Bundler, "friendly errors" do
   context "with invalid YAML in .gemrc" do
+    context "with the old ~/.gemrc" do
+      before do
+        File.open(home(".gemrc"), "w") do |f|
+          f.write "invalid: yaml: hah"
+        end
+      end
+
+      after do
+        FileUtils.rm(home(".gemrc"))
+      end
+
+      it "reports a relevant friendly error message" do
+        gemfile <<-G
+          source "#{file_uri_for(gem_repo1)}"
+          gem "rack"
+        G
+
+        bundle :install, :env => { "DEBUG" => "true" }
+
+        expect(err).to include("Failed to load #{home(".gemrc")}")
+        expect(exitstatus).to eq(0) if exitstatus
+      end
+    end
+
+    context "with XDG_CONFIG_HOME" do
       let(:config_home) { File.dirname(Gem.configuration.config_file_name) }
 
       before do
@@ -35,6 +60,7 @@ RSpec.describe Bundler, "friendly errors" do
         expect(exitstatus).to eq(0) if exitstatus
       end
     end
+  end
 
   it "calls log_error in case of exception" do
     exception = Exception.new