Escape invalid byte sequence in Exception

This fixes #141.

Author: aycabta

lib/irb.rb

@@ -578,6 +578,29 @@ def eval_input
  end
  end
 
+ def convert_invalid_byte_sequence(str)
+ str = str.force_encoding(Encoding::ASCII_8BIT)
+ conv = Encoding::Converter.new(Encoding::ASCII_8BIT, Encoding::UTF_8)
+ dst = String.new
+ begin
+ ret = conv.primitive_convert(str, dst)
+ case ret
+ when :invalid_byte_sequence
+ conf.insert_output(conf.primitive_errinfo[3].dump[1..-2])
+ redo
+ when :undefined_conversion
+ c = conv.primitive_errinfo[3].dup.force_encoding(conv.primitive_errinfo[1])
+ conv.insert_output(c.dump[1..-2])
+ redo
+ when :incomplete_input
+ conv.insert_output(conv.primitive_errinfo[3].dump[1..-2])
+ when :finished
+ end
+ break
+ end while nil
+ dst
+ end
+
  def handle_exception(exc)
  if exc.backtrace && exc.backtrace[0] =~ /\/irb(2)?(\/.*|-.*|\.rb)?:/ && exc.class.to_s !~ /^IRB/ &&
  !(SyntaxError === exc) && !(EncodingError === exc)
@@ -621,7 +644,8 @@ def handle_exception(exc)
  end
  puts messages.reverse
  end
- m = exc.to_s.split(/\n/)
+ converted_exc_s = convert_invalid_byte_sequence(exc.to_s.dup)
+ m = converted_exc_s.split(/\n/)
  print "#{attr[1]}#{exc.class} (#{attr[4]}#{m.shift}#{attr[0, 1]})#{attr[]}\n"
  puts m.map {|s| "#{attr[1]}#{s}#{attr[]}\n"}
  if attr == ATTR_PLAIN

test/irb/test_raise_no_backtrace_exception.rb

@@ -13,5 +13,13 @@ def e.backtrace; nil; end
  raise e
 IRB
  end
+
+ def test_raise_exception_with_invalid_byte_sequence
+ skip if RUBY_ENGINE == 'truffleruby'
+ bundle_exec = ENV.key?('BUNDLE_GEMFILE') ? ['-rbundler/setup'] : []
+ assert_in_out_err(bundle_exec + %w[-rirb -W0 -e IRB.start(__FILE__) -- -f --], <<~IRB, /StandardError \(A\\xF3B\)/, [])
+ raise StandardError, "A\\xf3B"
+ IRB
+ end
  end
 end