Shoulda matchers `allow_value` bug

example.rb

require 'active_model'

class Example
  include ActiveModel::Model

  validates :foo, inclusion: [1]

  attr_accessor :foo
end

example_spec.rb

require 'date'
require_relative 'example'
require 'shoulda/matchers'

RSpec.describe Example do
  include Shoulda::Matchers::ActiveModel

  subject { described_class.new }

  it { should allow_values(1).for(:foo)    } # this should pass and does
  it { should allow_values(2).for(:foo)    } # this should fail and does
  it { should allow_values(2, 1).for(:foo) } # this should fail and does
  it { should allow_values(1, 2).for(:foo) } # this should fail and doesn't
end

output.txt

Example
  should allow foo to be set to 1
  should allow foo to be set to 2 (FAILED - 1)
  should allow foo to be set to any of [2, 1] (FAILED - 2)
  should allow foo to be set to any of [1, 2]

Failures:

  1) Example should allow foo to be set to 2
     Failure/Error: it { should allow_values(2).for(:foo)    } # this should fail and does

       Did not expect errors when foo is set to 2,
       got errors:
       * "is not included in the list" (attribute: foo, value: 2)
     # ./example_spec.rb:11:in `block (2 levels) in <top (required)>'

  2) Example should allow foo to be set to any of [2, 1]
     Failure/Error: it { should allow_values(2, 1).for(:foo) } # this should fail and does

       Did not expect errors when foo is set to 2,
       got errors:
       * "is not included in the list" (attribute: foo, value: 2)
     # ./example_spec.rb:12:in `block (2 levels) in <top (required)>'

Finished in 0.40018 seconds (files took 1.86 seconds to load)
4 examples, 2 failures

Failed examples:

rspec ./example_spec.rb:11 # Example should allow foo to be set to 2
rspec ./example_spec.rb:12 # Example should allow foo to be set to any of [2, 1]

run.sh

rspec example_spec.rb --format documentation > output.txt