debug

Gemfile

@@ -52,6 +52,7 @@ group :coverage do
 end
 
 if defined?(RUBY_PLATFORM) && RUBY_PLATFORM == 'java'
+  puts 'JRUBY detected, installing tempfile'
   gem 'tempfile.rb', require: false
 end
 

spec/rspec/support/spec/stderr_splitter_spec.rb

@@ -102,7 +102,9 @@
   # This is essentially what the `to_stderr_from_any_process` matcher attempts
   # to do in CaptureStreamToTempfile.
   it 'is able to restore the stream from a cloned StdErrSplitter' do
+    puts "=> #{RUBY_ENGINE}"
     if RSpec::Support::Ruby.jruby? && Tempfile.new("foo").is_a?(File) == false
+      puts 'JRUBY detected, requiring tempfile'
       require 'tempfile'
     end