Unexpected ruby error (failed to load encoding)

[dduugg]

• Ruby version: 2.6.10
• Rubyfmt git sha: 266b47b (v0.8.1)

Input file

https://raw.githubusercontent.com/Homebrew/brew/f71294d483e1ce9920fd10d8169b1419c0ba41fb/Library/Homebrew/test/cli/parser_spec.rb

Rubyfmt's output

$ rubyfmt Library/Homebrew/test/cli/parser_spec.rb
Error! source: Library/Homebrew/test/cli/parser_spec.rb
Rubyfmt experienced an unexpected ruby error: #<LoadError: failed to load encoding (Windows-31J)>

This breaks because

An error occurred (I was curious if rubyfmt would be a better fit for the repo than rubocop, but the latter is able to format this file.)