/ruby/spec/mspec/lib/mspec/helpers/tmp.rb:50:in `insert': can't modify frozen String: "mspec-multi-0" (FrozenError) from /ruby/spec/mspec/lib/mspec/helpers/tmp.rb:50:in `tmp' from /ruby/spec/mspec/lib/mspec/runner/parallel.rb:23:in `block in launch_children' from /ruby/spec/mspec/lib/mspec/runner/parallel.rb:22:in `times' from /ruby/spec/mspec/lib/mspec/runner/parallel.rb:22:in `each' from /ruby/spec/mspec/lib/mspec/runner/parallel.rb:22:in `map' from /ruby/spec/mspec/lib/mspec/runner/parallel.rb:22:in `launch_children' from /ruby/spec/mspec/lib/mspec/runner/parallel.rb:97:in `run' from /ruby/spec/mspec/lib/mspec/commands/mspec.rb:97:in `multi_exec' from /ruby/spec/mspec/lib/mspec/commands/mspec.rb:111:in `run' from /ruby/spec/mspec/lib/mspec/utils/script.rb:276:in `main' from ../mspec/bin/mspec:7:in `
'