Arrays?!

comma.rb

class Stuff
  def initialize(params = {})
    @foo_name       = params.fetch(:foo_name)
    @foo_identifier = params.fetch(:foo_identifier)
    @bar_name       = params.fetch(:bar_name),
    @bar_identifier = params.fetch(:bar_identifier)
  end

  def to_a
    [
      @foo_name,
      @foo_identifier,
      @bar_name,
      @bar_identifier,
    ]
  end
end

p Stuff.new(foo_name: 'The Foo', foo_identifier: '/foo', bar_name: 'The Bar', bar_identifier: '/bar')
# #<Stuff:0x007fe343848068 @foo_name="The Foo", @foo_permalink="/foo", @bar_permalink="/bar", @bar_name=["The Bar", "/bar"]>

Why is bar_name an array?!