a repro script for a bug in the way ruby parser handles splats followed by commas

parser_splat_comma_repro.rb

require 'minitest/autorun'
require 'ruby_parser'

FirstException = Class.new(StandardError)
SecondException = Class.new(StandardError)
ThirdException = Class.new(StandardError)

EXCEPTIONS = [SecondException]

def my_method(error)
    raise error
rescue FirstException, *EXCEPTIONS, ThirdException => e
    e.to_s
end

class TestArraySplatFollowedByComma < Minitest::Test
  def test_that_first_exception_is_caught_correctly
    assert_equal "FirstException", my_method(FirstException)
  end

  def test_that_splatted_exception_is_caught_correctly
    assert_equal "SecondException", my_method(SecondException)
  end

  def test_that_last_exception_is_caught_correctly
    assert_equal "ThirdException", my_method(ThirdException)
  end
end

class TestRubyParserBehaviour < Minitest::Test
  def test_that_the_code_is_parsed_correctly
    RubyParser.for_current_ruby.parse(method(:my_method).source)
  end
end